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Author Topic:   Autolite 4100 won't idle (long, post-lots of ????)
deadhead
Gearhead

Posts: 153
From:
Registered: Sep 2002

posted 11-01-2002 11:54 AM     Click Here to See the Profile for deadhead   Click Here to Email deadhead     Edit/Delete Message   Reply w/Quote
I need some help again with my 4100.

I've put about 200 or so miles on the rebuild, and had some time to check a few things. The engine was idling rough, but running okay--just okay--at speed. It sounded like I had an exhaust leak, but all the header bolts are tight. Sooooo, I retorqued the manifold bolts for my Weiand Action-Plus. They seemed quite loose. I was able to turn all of them easily at 14 ft/pounds, then torqued them to 16 ft/pounds. I replaced the petrified PCV grommet on the valve cover and now I have a good, tight seal on the PCV valve. I replaced the carb base gaskets since it appeared I had some leaking. While the carb was off, I checked the power valve and found the power valve did not have a gasket on it. (Friends shouldn't let friends drink and rebuild carbs).

I DO NOT have a secondary check ball installed. The rebuild kits I have inspected at the local parts stores don't come with a ball small enough to fit. In fact, they don't indicate a ball is needed in the parts blow-up, which is why there isn't one.

I put everything back together, and now the engine won't idle. When I start it up, she runs at a fairly high rpm for a few seconds, then stumbles and dies. Fanning the gas pedal will keep her running, but she's nowhere near driveable.

I'm postulating I had a vacuum leak at the manifold, and now the carb/engine is behaving completely differently, but the idle problem sounds like a float level issue. I didn't mess with the floats. Could I now be making enough vacuum that the secondaries are effected due to the lack of the check ball?

The PCV system was not sealing before, but the engine won't idle either with the valve removed from the valve cover. I'm using the stock FORD riser plate with the PCV fitting. Does the open cavitied/open side of the riser plate go up towards the carb, or down towards the manifold? (I know it sounds stupid, but I'm shooting in the dark).
Since the Weiand manifold doesn't have all the cavities at the carb opening the FORD manifold did, it seems like I'd be better off with a phenolic riser plate and a brass fitting for the hose. Could I just use one of the available vacuum holes in a manifold runner to hook up the PCV hose and get rid of the riser altogether?

The Shop Manual states the secondary throttle plate setting should be 3/4 turns after the screw contacts the lever. Is that a good number?

Should the hot engine idle speed adjusting screw be preloaded at all after it touches the throttle shaft lever BEFORE trying to adjust the idle mixture screws?

Is there anything else I can use for the secondary check ball? Unfortunately, the standard BB size is the size of the accelerator check ball, but they're too big to use as the secondary check ball.

HELP!!!!!!! My car is stuck in my friends garage and my wife is PISSED!!!!!!!!

deadhead

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Moneymaker
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From: Lyons, IL, USA
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posted 11-01-2002 12:02 PM     Click Here to See the Profile for Moneymaker   Click Here to Email Moneymaker     Edit/Delete Message   Reply w/Quote
Don't worry about the secondary check ball.
Start the car and carefully look down the primaries and see if fuel is trickling out. It should not.
If it is then....
Pull off the top and measure the float levels.
Should not be less than 11/16 or so for a street car.
Once that has been check get back to me(us).
Don't put the top back on. I have some other possibilities. You can run the car with the top off for observation purposes.
Don't attempt this before checking wiht me(us) first though please.

------------------
Alex Denysenko
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The Barry of BarrysGrrl

Quote #1: "I never met a magazine mechanic I liked."
Quote #2: "Make sure brain is in gear before engaging mouth!"
Quote #3: "If you can't run with the big dogs, stay on the porch!"

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deadhead
Gearhead

Posts: 153
From:
Registered: Sep 2002

posted 11-01-2002 12:10 PM     Click Here to See the Profile for deadhead   Click Here to Email deadhead     Edit/Delete Message   Reply w/Quote
Alex,

I'm typing to you from the local public library--my friend's computer is down for the count.

I checked the floats at 29/64s yesterday, both primary and secondary. I can't tell if there's fuel trickling. Should I readjust the float level first, and then get back to you?

deadhead

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deadhead
Gearhead

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posted 11-01-2002 12:22 PM     Click Here to See the Profile for deadhead   Click Here to Email deadhead     Edit/Delete Message   Reply w/Quote
Alex,

Are you talking wet float height or fuel height?

deadhead

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Moneymaker
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Posts: 19751
From: Lyons, IL, USA
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posted 11-01-2002 12:26 PM     Click Here to See the Profile for Moneymaker   Click Here to Email Moneymaker     Edit/Delete Message   Reply w/Quote
OK, we'll do it this way.
First see if fuel is trickling from the boosters.
Did you install the booster gaskets correctly? Did you mix up the boosters by any chance?
Did you remember to install the pin back in the primary booster cavity?
Yes,then check the float levels.
I almost sounds as if the needles are popping off of the seats a bit.
If you have a fire extinguisher (just in case) then you can try and start the car with the top off. You must hold the float tangs down on the needles while attempting this. I am almost afraid to recomend this to a first timer as it takes some serious concentration. The carb will run as normal with the top off and you will be able to see iff the needles are popping off of the seats.

------------------
Alex Denysenko
Co-Administrator and Moderator

NHRA/IHRA/SRA member and licensed Superstock driver
MCA member# 53321
NHRA and IHRA SS/LA National Record Holder '00, '01, & '02
Fleet of FoMoCo products including 88 ASC McLaren Mustang #28
Professional Manwhore
The Barry of BarrysGrrl

Quote #1: "I never met a magazine mechanic I liked."
Quote #2: "Make sure brain is in gear before engaging mouth!"
Quote #3: "If you can't run with the big dogs, stay on the porch!"

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Moneymaker
Administrator

Posts: 19751
From: Lyons, IL, USA
Registered: May 99

posted 11-01-2002 12:27 PM     Click Here to See the Profile for Moneymaker   Click Here to Email Moneymaker     Edit/Delete Message   Reply w/Quote
Float height.

------------------
Alex Denysenko
Co-Administrator and Moderator

NHRA/IHRA/SRA member and licensed Superstock driver
MCA member# 53321
NHRA and IHRA SS/LA National Record Holder '00, '01, & '02
Fleet of FoMoCo products including 88 ASC McLaren Mustang #28
Professional Manwhore
The Barry of BarrysGrrl

Quote #1: "I never met a magazine mechanic I liked."
Quote #2: "Make sure brain is in gear before engaging mouth!"
Quote #3: "If you can't run with the big dogs, stay on the porch!"

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deadhead
Gearhead

Posts: 153
From:
Registered: Sep 2002

posted 11-01-2002 12:31 PM     Click Here to See the Profile for deadhead   Click Here to Email deadhead     Edit/Delete Message   Reply w/Quote
Alex,

As I said, the car was running before I did all this, so I don't think I swapped out the boosters.

I believe I installed the booster gaskets correctly.

I don't want to attempt starting her yet with the top off. When she does light up, she's really screaming, probably 2000 or more rpms.

Is 11/16 the fuel height or the wet float height?

Thanks much,

deadhead

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deadhead
Gearhead

Posts: 153
From:
Registered: Sep 2002

posted 11-01-2002 12:33 PM     Click Here to See the Profile for deadhead   Click Here to Email deadhead     Edit/Delete Message   Reply w/Quote
Alex,

Sooooo, my wet float height is off by almost a 1/4 of an inch. I'll fix that first, then maybe I can drive over here in the 'Stang.

deadhead

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Moneymaker
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Posts: 19751
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posted 11-01-2002 12:55 PM     Click Here to See the Profile for Moneymaker   Click Here to Email Moneymaker     Edit/Delete Message   Reply w/Quote
It sounds as if you have the floats WAY high.
If you are 1/4 inch off then the fuel level is almost at the top of the bowl. That's your problem for sure.

------------------
Alex Denysenko
Co-Administrator and Moderator

NHRA/IHRA/SRA member and licensed Superstock driver
MCA member# 53321
NHRA and IHRA SS/LA National Record Holder '00, '01, & '02
Fleet of FoMoCo products including 88 ASC McLaren Mustang #28
Professional Manwhore
The Barry of BarrysGrrl

Quote #1: "I never met a magazine mechanic I liked."
Quote #2: "Make sure brain is in gear before engaging mouth!"
Quote #3: "If you can't run with the big dogs, stay on the porch!"

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65Acode
Journeyman

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From: Houston,TX
Registered: Sep 2002

posted 11-01-2002 05:31 PM     Click Here to See the Profile for 65Acode     Edit/Delete Message   Reply w/Quote
I love a happy ending!!

[This message has been edited by 65Acode (edited 11-01-2002).]

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deadhead
Gearhead

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posted 11-02-2002 11:35 AM     Click Here to See the Profile for deadhead   Click Here to Email deadhead     Edit/Delete Message   Reply w/Quote
Alex,

Thanks much for your help. I can get the car to run now, but the idle is still off--she won't idle by herself, but now she'll run continuously at a higher rpm. The float height was obviously an issue.

However, the car ran and idled, although not perfectly, before I did the few items I mentioned. Now she still won't idle. What could retorquing the intake, adding the power valve gasket, installing a new PCV grommet and new carb base gaskets have done?

I'm hoping I fixed a larger problem and now simply have to go back through the normal tuning steps.

Any advice on the other questions I asked?

Thanks much,

deadhead

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Moneymaker
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posted 11-02-2002 04:35 PM     Click Here to See the Profile for Moneymaker   Click Here to Email Moneymaker     Edit/Delete Message   Reply w/Quote
What base gasket did you use?
Try screwing the mixture screws almost all the way in.
Did you mess with the timing?
Are you sure the fuel filter is not obstructed?

------------------
Alex Denysenko
Co-Administrator and Moderator

NHRA/IHRA/SRA member and licensed Superstock driver
MCA member# 53321
NHRA and IHRA SS/LA National Record Holder '00, '01, & '02
Fleet of FoMoCo products including 88 ASC McLaren Mustang #28
Professional Manwhore
The Barry of BarrysGrrl

Quote #1: "I never met a magazine mechanic I liked."
Quote #2: "Make sure brain is in gear before engaging mouth!"
Quote #3: "If you can't run with the big dogs, stay on the porch!"

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deadhead
Gearhead

Posts: 153
From:
Registered: Sep 2002

posted 11-04-2002 05:27 PM     Click Here to See the Profile for deadhead   Click Here to Email deadhead     Edit/Delete Message   Reply w/Quote
I can get her to idle now, but she's surely not street ready. She's still near impossible to start cold without starting fluid and it was a pretty nice day here in Hampton Roads, VA.

When I lightly step on the gas while she's parked, she hesitates, then accelerates and stays at a higher rpm for a few seconds even after I let off the gas, then slowly reduces her rpm back to idle. It doesn't appear the accelerator pump nozzles do anything but dribble unless you ready stomp on it. I didn't have that problem before I made the changes I outlined in the original post.

The wet float height is somewhere greater than 42/64 but less than 47/64. I've got the accelerator pump arm on the interior hole and #3 hole. She's got #53 and #59 jets, timing is at 10 degrees, the idle adjustment screws are 3 turns out. She kept getting easier to manage as the idle screws came out. I may try another half a turn, but I'm not sure how far out I can go. The primary venturi booster has a D and a small 4 on it. The secondary has an F and a small 4. The ends of the interior tubes on both the boosters are squeezed together into a small hole, like a nipple.

I haven't found any Fel-Pro carb base geaskets yet, so I installed another fresh gasket from the rebuild kit. It has four holes for the barrels, but no other special features.

I'll check the fuel filter again, but it seemed fine during the rebuild.

deadhead

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deadhead
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posted 11-04-2002 08:30 PM     Click Here to See the Profile for deadhead   Click Here to Email deadhead     Edit/Delete Message   Reply w/Quote
I replaced the primary venturi booster with one out of my old two-barrel. It has a J and a small 3 on it. The hesitation and lingering rpms after stepping on the gas disappeared. But I still think things are awry.

I failed to mention in my last post that I have the idle speed adjustment screw bottomed out against the spring AND the idle mixture screws at 3 and-a-half turns out. That can't be right, can it?

deadhead

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johnmustang
Gearhead

Posts: 4504
From: Vancouver Island , British Columbia , Canada
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posted 11-04-2002 08:40 PM     Click Here to See the Profile for johnmustang   Click Here to Email johnmustang     Edit/Delete Message   Reply w/Quote
I had the same problem with mine , and , it turned out to be the throttle shaft was loose and I was getting a vacuum leak from it. It had worn out , and , I am very sure that at some point in it`s long life it had the wrong throttle spring on it and it was hooked up to the shaft itself which will cause this problem. Sounds like you may just have a worn out tired carb

JOHN

------------------
65 2+2 FASTBACK
68 COUPE (SOLD)
87 TAURUS WAGON
98 F150 XLT TRITON V8 4.6, 4 WHEEL DRIVE
Member:Vancouver Island Mustang Association
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Moneymaker
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Posts: 19751
From: Lyons, IL, USA
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posted 11-04-2002 09:32 PM     Click Here to See the Profile for Moneymaker   Click Here to Email Moneymaker     Edit/Delete Message   Reply w/Quote
I guess this is a prime reason where the expression "don't try this at home" came from.
I think that you have the accelerator pump spring in backwards also. That would attribute to your lack of pump shot.
By swaping out the booster and gaining an improvement, that tells us that something went wrong with the previous removal and possibly the gasket placement.

------------------
Alex Denysenko
Co-Administrator and Moderator

NHRA/IHRA/SRA member and licensed Superstock driver
MCA member# 53321
NHRA and IHRA SS/LA National Record Holder '00, '01, & '02
Fleet of FoMoCo products including 88 ASC McLaren Mustang #28
Professional Manwhore
The Barry of BarrysGrrl

Quote #1: "I never met a magazine mechanic I liked."
Quote #2: "Make sure brain is in gear before engaging mouth!"
Quote #3: "If you can't run with the big dogs, stay on the porch!"

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deadhead
Gearhead

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From:
Registered: Sep 2002

posted 11-05-2002 10:35 AM     Click Here to See the Profile for deadhead   Click Here to Email deadhead     Edit/Delete Message   Reply w/Quote
I suppose the boosters might have gotten switched but the one off the two-barrel I replaced it with does not have the squeezed end on the pick-up tubes. Any idea what the purpose of that would have been?

I suppose the one I took out could be clogged somehow. I've got some fine wire to run through it to see if it's obstructed. I'll also try switching them around, and I'll check the pump spring, and I'll check the throttle shaft, and I'll check my wallet...

Thanks,

deadhead

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deadhead
Gearhead

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posted 11-05-2002 02:27 PM     Click Here to See the Profile for deadhead   Click Here to Email deadhead     Edit/Delete Message   Reply w/Quote
Alex,

You were right, again. The accelerator pump spring was in backwards. Unfortunately, that's the way it's pictured in the diagram included with the rebuild kit.

Soooooo, I turned the spring around and put everything back together. I won't have a new rebuild kit till tomorrow. I also took out the fuel filter and examined it. There was a bit of rust and scale in the pail after I dumped the contents of the filter out in it. I'll replace it again.

This time, she started to idle fairly nicely but she wouldn't hold a higher rpm without surging and dying. I was under the hood while she was running and I could see fuel dribbling out of the boosters. When she died I heard a gurgling sound from the front of the carb that lasted a few seconds. I popped open the lid and the fuel level was at the top of the carb, above the floats. Please tell me the elastomer valve is shot and I don't have some other issue. If it's not the elastomer valve, could the fuel filter have been so clogged that now I have to reset the float level. I can try doing the latter tonight, but I won't be able to deal with the elastomer valve till tomorrow.

Thanks,

deadhead

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Moneymaker
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posted 11-05-2002 03:09 PM     Click Here to See the Profile for Moneymaker   Click Here to Email Moneymaker     Edit/Delete Message   Reply w/Quote
Well, fortunatly we have enough UBB space to help get you through this Deadhead.

In all fairness, the backward spring issue is not entirely your fault. If you look closely at the instruction illustrations you will find that there are two of them. One is for the very eary 4100 with the extended nose accelerator pump body and the other is for the later more common pump housing. They early one requires the spring to be installed backwards. Most first time 4100 rebuilders make that mistake.

------------------
Alex Denysenko
Co-Administrator and Moderator

NHRA/IHRA/SRA member and licensed Superstock driver
MCA member# 53321
NHRA and IHRA SS/LA National Record Holder '00, '01, & '02
Fleet of FoMoCo products including 88 ASC McLaren Mustang #28
Professional Manwhore
The Barry of BarrysGrrl

Quote #1: "I never met a magazine mechanic I liked."
Quote #2: "Make sure brain is in gear before engaging mouth!"
Quote #3: "If you can't run with the big dogs, stay on the porch!"

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deadhead
Gearhead

Posts: 153
From:
Registered: Sep 2002

posted 11-05-2002 04:55 PM     Click Here to See the Profile for deadhead   Click Here to Email deadhead     Edit/Delete Message   Reply w/Quote
Alex,

I'd really like to get the 4100 working right. I'm just finding it hard to believe the more things I fix the worse she runs.

deadhead

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SteveLaRiviere
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From: Saco, Maine
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posted 11-05-2002 05:04 PM     Click Here to See the Profile for SteveLaRiviere   Click Here to Email SteveLaRiviere     Edit/Delete Message   Reply w/Quote
quote:
Originally posted by deadhead:
I was under the hood while she was running and I could see fuel dribbling out of the boosters. When she died I heard a gurgling sound from the front of the carb that lasted a few seconds. I popped open the lid and the fuel level was at the top of the carb, above the floats. Please tell me the elastomer valve is shot and I don't have some other issue. If it's not the elastomer valve, could the fuel filter have been so clogged that now I have to reset the float level. I can try doing the latter tonight, but I won't be able to deal with the elastomer valve till tomorrow.

If you are sure that your folat level is correct, check your needle&seat seat assembly. You replaced the gasket between the seat and the carb body, right?

------------------
'70 Mustang Mach 1 - '72 Mustang Sprint - '94 F-150

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SteveLaRiviere
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posted 11-05-2002 05:06 PM     Click Here to See the Profile for SteveLaRiviere   Click Here to Email SteveLaRiviere     Edit/Delete Message   Reply w/Quote
quote:
Originally posted by deadhead:
I'd really like to get the 4100 working right. I'm just finding it hard to believe the more things I fix the worse she runs.

Try it some time with a service manager yelling at you.

Don't give up. This is when the learning begins.

------------------
'70 Mustang Mach 1 - '72 Mustang Sprint - '94 F-150

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Moneymaker
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Posts: 19751
From: Lyons, IL, USA
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posted 11-05-2002 05:26 PM     Click Here to See the Profile for Moneymaker   Click Here to Email Moneymaker     Edit/Delete Message   Reply w/Quote
And......... the customer standing next to the service manager.

------------------
Alex Denysenko
Co-Administrator and Moderator

NHRA/IHRA/SRA member and licensed Superstock driver
MCA member# 53321
NHRA and IHRA SS/LA National Record Holder '00, '01, & '02
Fleet of FoMoCo products including 88 ASC McLaren Mustang #28
Professional Manwhore
The Barry of BarrysGrrl

Quote #1: "I never met a magazine mechanic I liked."
Quote #2: "Make sure brain is in gear before engaging mouth!"
Quote #3: "If you can't run with the big dogs, stay on the porch!"

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deadhead
Gearhead

Posts: 153
From:
Registered: Sep 2002

posted 11-06-2002 08:10 PM     Click Here to See the Profile for deadhead   Click Here to Email deadhead     Edit/Delete Message   Reply w/Quote
OK. Been fighting with her since about 1530 this afternoon. I rebuilt the 4100 very carefully. I no longer have the problem of the fuel bowls filling up to the top. I guess the new elastomer valve took care of that.

Unfortunately, she still won't idle and won't hold ANY rpm without fanning the gas pedal. All the vacuum passages appear to be clear. I did find two things wrong. There was a barely visible vacuum port behind the manual choke cable mount that was not plugged. It looks like a screw hole. It's plugged now. The power valve cover is warped, but it's not leaking fuel. Everything else seems as it should be.

She won't idle and she won't hold any higher rpm. Any ideas?

deadhead

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johnmustang
Gearhead

Posts: 4504
From: Vancouver Island , British Columbia , Canada
Registered: Nov 2001

posted 11-06-2002 09:22 PM     Click Here to See the Profile for johnmustang   Click Here to Email johnmustang     Edit/Delete Message   Reply w/Quote
Check the main throttle shaft , that is what was wrong with mine , had it silver soldered and it looks and works great


JOHN

------------------
65 2+2 FASTBACK
68 COUPE (SOLD)
87 TAURUS WAGON
98 F150 XLT TRITON V8 4.6, 4 WHEEL DRIVE
Member:Vancouver Island Mustang Association
M&M #1710
MyPhotoPage
MY TRUCK

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Moneymaker
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Posts: 19751
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posted 11-06-2002 10:12 PM     Click Here to See the Profile for Moneymaker   Click Here to Email Moneymaker     Edit/Delete Message   Reply w/Quote
Replace or eliminate the power valve. A Holley valve or plug will work. If you elect to continue using a vlave get a 5.5 or 4.5 Holley. If you can't get a plug or a new valve asap then reinstall the original valve.

------------------
Alex Denysenko
Co-Administrator and Moderator

NHRA/IHRA/SRA member and licensed Superstock driver
MCA member# 53321
NHRA and IHRA SS/LA National Record Holder '00, '01, & '02
Fleet of FoMoCo products including 88 ASC McLaren Mustang #28
Professional Manwhore
The Barry of BarrysGrrl

Quote #1: "I never met a magazine mechanic I liked."
Quote #2: "Make sure brain is in gear before engaging mouth!"
Quote #3: "If you can't run with the big dogs, stay on the porch!"

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deadhead
Gearhead

Posts: 153
From:
Registered: Sep 2002

posted 11-07-2002 11:43 AM     Click Here to See the Profile for deadhead   Click Here to Email deadhead     Edit/Delete Message   Reply w/Quote
I replaced the #53 main jets with #55s. Now she'll run at a higher rpm, but I still can't get her to idle. She sounds much different than with the 53s--a much deeper exhaust note. I'm running #59s in the secondaries. I turned the idle mixture screws out a half-turn at a time all the way to 4 turns out and it didn't seem to make a difference in how she idled. The idle speed screw is still turned in far enough the fast idle screw cannot hit the cam, but when I close the choke plate, the rpms go up quite a bit anyway. Isn't that usually a sign of a lean mixture? I plan on trying the 59s in front and a pair of 67s in back--those are the only other jets I've been able to "find", but I'll replace or eliminate the power valve first. It was brand new out of the rebuild kit, however.

deadhead

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deadhead
Gearhead

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From:
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posted 11-07-2002 12:35 PM     Click Here to See the Profile for deadhead   Click Here to Email deadhead     Edit/Delete Message   Reply w/Quote
By the way, I'm running Autolite platinum 45s. They don't show much color, but I haven't had the car on the road since this debacle began. From the looks of the electrode, this is a very hot plug. I had Autolite 35s in there before, but couldn't find any when I needed them. Any other plug recommendations?

deadhead

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1_ZoNiE
Gearhead

Posts: 490
From: Arizona - M&M Member No. 1968 & Owner/Driver of a 1968 Mustang Coupe! ~Happiness is Matching Numbers~
Registered: Mar 2002

posted 11-07-2002 02:28 PM     Click Here to See the Profile for 1_ZoNiE   Click Here to Email 1_ZoNiE     Edit/Delete Message   Reply w/Quote
I have a 4100 on a stock manifold. I went and rebuild the carb as required. However, when it came time to try it out I had exactly the same problem described above. Drove my neighbors nuts firing it up at one in the morning and trying to idle it down only to have it die on me. Anyway, the long of the short is this; try a diffrent base gasket before giving up. The following is what I found to work Napa G 27190. Just any ole' 4 bbl. gasket won't do for this carb. I know by been there done that.

BTW if you remove the carb from the manifold do you see any black areas on the carb base or the manifold where it bolts down to?

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deadhead
Gearhead

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posted 11-07-2002 04:23 PM     Click Here to See the Profile for deadhead   Click Here to Email deadhead     Edit/Delete Message   Reply w/Quote
I checked all the plugs after fanning the pedal for a few minutes while the #55 mains were installed. They all have wet threads and just the slightest bit of black soot on them. The plugs were basically white with the 53s, but as I mentioned, they're a hot plug.

I replaced the power valve with a Holley #5. They didn't have a plug. The throttle response is crisp, but it still won't idle and it really won't hold any reasonable rpm without stalling. I can keep her running by fanning the gas pedal. I had it running on it's own with the choke plate mostly closed. That has to be a clue.

I had the wife try to keep the engine running while I removed the carb lid. When I lifted the gasket, I noticed the fuel coming out of the needle valve was foamy. Is that normal or another clue? I don't appear to have any fuel leaks. The fuel pump has been in the car since I bought it in 1989. It's a Carter non-rebuildable pump.

deadhead

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deadhead
Gearhead

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From:
Registered: Sep 2002

posted 11-07-2002 04:29 PM     Click Here to See the Profile for deadhead   Click Here to Email deadhead     Edit/Delete Message   Reply w/Quote
1_zonie,

Were you using the Ford riser with the PCV connection? I've got that between the carb and the manifold.

I had a CarQuest gasket on there that only had holes for the barrels--no other distinguishing features. I have since replaced it with the gasket that came with the rebuild kit. The gasket material that creates the four holes for the barrels does not quite meet in the center, so it's open there. It also has two small holes, one between the primaries and one between the secondaries. It made no change in the way she runs.

deadhead

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deadhead
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posted 11-07-2002 06:29 PM     Click Here to See the Profile for deadhead   Click Here to Email deadhead     Edit/Delete Message   Reply w/Quote
Alex?????

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Moneymaker
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posted 11-07-2002 06:42 PM     Click Here to See the Profile for Moneymaker   Click Here to Email Moneymaker     Edit/Delete Message   Reply w/Quote
I'm here........... Still steaming from my miserable HP all day phone ordeal. Got nothing done, no money made and didn't even eat lunch!


Oh well, that's my problem.

Get a can of carb cleaner or starting fluid. With the engine running as best as you can start spraying the stuff around the base of the carb and spacer. If the idle climbs way up you have one severe vaccum leak. Maybe you even cracked the throttle body in one of the R&R trips. If that doesn't show anything then keep spraying around he intake manifold where it meets the heads. Look for a dramatic RPM increase when you sray the stuff anywhere. I'll be around.

------------------
Alex Denysenko
Co-Administrator and Moderator

NHRA/IHRA/SRA member and licensed Superstock driver
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NHRA and IHRA SS/LA National Record Holder '00, '01, & '02
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The Barry of BarrysGrrl

Quote #1: "I never met a magazine mechanic I liked."
Quote #2: "Make sure brain is in gear before engaging mouth!"
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indyphil
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From: Lafayette, IN, USA
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posted 11-07-2002 06:47 PM     Click Here to See the Profile for indyphil   Click Here to Email indyphil     Edit/Delete Message   Reply w/Quote
Just a quick note (I dont have much help to offer) but you must not attach the PCV to the manifold itself. If you do that it will create a lean condition on the cylinder that runs from that part of the manifold. You have to connect the PCV to either the carb base, the spacer under the carb or into the air cleaner above the carb.

good luck with the carb.

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SteveLaRiviere
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posted 11-07-2002 07:15 PM     Click Here to See the Profile for SteveLaRiviere   Click Here to Email SteveLaRiviere     Edit/Delete Message   Reply w/Quote
Can you stall it with your hand over the choke?

------------------
'70 Mustang Mach 1 - '72 Mustang Sprint - '94 F-150

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1_ZoNiE
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Posts: 490
From: Arizona - M&M Member No. 1968 & Owner/Driver of a 1968 Mustang Coupe! ~Happiness is Matching Numbers~
Registered: Mar 2002

posted 11-07-2002 08:44 PM     Click Here to See the Profile for 1_ZoNiE   Click Here to Email 1_ZoNiE     Edit/Delete Message   Reply w/Quote
quote:
Originally posted by deadhead:
1_zonie,

Were you using the Ford riser with the PCV connection? I've got that between the carb and the manifold.


The answer to the question is yes! If this is the case you'll need two of those gaskets. When I put mine together I swore I had the gasket to the outer edge of the base. But, I found out that it wasn't quite there on that spacer. The outstanding feature I noticed, when I took the carb back off, was a blacken area where it was massively sucking air each side of the spacer to manifold (or was that carb to spacer - I don't remember now cause once this carb goes on it will stay on with no problems for a long time). Trust me on this! Two of those gaskets from Napa (one below the spacer - spacer to manifold and one above the spacer - spacer to carb) should do it! If I'm wrong then ....

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deadhead
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posted 11-08-2002 11:43 AM     Click Here to See the Profile for deadhead   Click Here to Email deadhead     Edit/Delete Message   Reply w/Quote
The saga continues...

I found the vacuum leak. Passenger side where the manifold and riser meet. I switched the $4.00 Mr. Gasket for a gasket included in the rebuild kit and that problem was solved. Had her all idling and such last night. HOWEVER, I can't get her to idle low enough, she's hovering around 1200 rpm, to put her into gear without stalling. I think I need some basic tuning advice.

Where do I start--idle speed screw, idle mixture screws, or timing? There's a point on the idle speed screw past which I can't turn the rpms down any more without her stalling. I used that as a baseline for the rest of the work. I thought I had everything wired, but she's making about 15 inches of vacuum at idle (for a while, I'll get to that in a minute), so when I hook the vacuum advance back up the rpms jump. She'll idle for a minute or two now, and then she'll die unless I fan the gas. The wet float height is at 11/16". The vacuum obviously drops as she stalls, but I can't tell if it's a symptom of something or simply the result of the stall.

I don't want to give up on the 4100, but I'd prefer to be driving the car.

deadhead

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SteveLaRiviere
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posted 11-08-2002 11:51 AM     Click Here to See the Profile for SteveLaRiviere   Click Here to Email SteveLaRiviere     Edit/Delete Message   Reply w/Quote
quote:
Originally posted by SteveLaRiviere:
Can you stall it with your hand over the choke?


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deadhead
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posted 11-08-2002 11:54 AM     Click Here to See the Profile for deadhead   Click Here to Email deadhead     Edit/Delete Message   Reply w/Quote
Steve,

I'll check that when I get back. I'm typing to you from the local public library.

If I can, what would it mean?

deadhead

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SteveLaRiviere
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posted 11-08-2002 12:32 PM     Click Here to See the Profile for SteveLaRiviere   Click Here to Email SteveLaRiviere     Edit/Delete Message   Reply w/Quote
If you can stall it, there are no vacuum leaks and if you can't there are. I'm betting it will smoothen up and idle nice when you do this. I think you have more vacuum leaks.

------------------
'70 Mustang Mach 1 - '72 Mustang Sprint - '94 F-150

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deadhead
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posted 11-08-2002 04:35 PM     Click Here to See the Profile for deadhead   Click Here to Email deadhead     Edit/Delete Message   Reply w/Quote
Covering the choke choked her. Not instantaneously, but pretty quick. I checked her all over for vacuum leaks with starting fluid and couldn't find anyplace even remotely suspect.

The problem I need help with now is this:

She'll run forever at a high rpm, say 2000, but won't keep running at 1200 for more than a minute or so. She'll idle, pretty smooth for a while, then run up to about 1500 rpm for a few seconds, then slowly die. I can keep her running by fanning the gas. I can't get her to idle below about 1200 at all, no matter what I do with the idle mixture, idle screw, or timing.

deadhead

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deadhead
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posted 11-09-2002 02:52 PM     Click Here to See the Profile for deadhead   Click Here to Email deadhead     Edit/Delete Message   Reply w/Quote
Anyone???? I'm out of ideas.

deadhead

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SteveLaRiviere
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posted 11-09-2002 03:50 PM     Click Here to See the Profile for SteveLaRiviere   Click Here to Email SteveLaRiviere     Edit/Delete Message   Reply w/Quote
That threw me off. I thought for sure you had a bad vacuum leak...

You verified that the floats are set right....

What I'd check next are the air bleeds. You may have one or more plugged, and that would cause vacuum to siphon fuel.

------------------
'70 Mustang Mach 1 - '72 Mustang Sprint - '94 F-150

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Moneymaker
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posted 11-09-2002 04:43 PM     Click Here to See the Profile for Moneymaker   Click Here to Email Moneymaker     Edit/Delete Message   Reply w/Quote
OK, there is only one or two culprits left if it will idle for a while then quit unless you fan it. It's either the fuel filter or fuel pump. You are running out of fuel. Strat it up and let it run at 1200 until it dies. Then don't do anything but remove the carb top and see if you have any fuel in the bowl.

------------------
Alex Denysenko
Co-Administrator and Moderator

NHRA/IHRA/SRA member and licensed Superstock driver
MCA member# 53321
NHRA and IHRA SS/LA National Record Holder '00, '01, & '02
Fleet of FoMoCo products including 88 ASC McLaren Mustang #28
Professional Manwhore
The Barry of BarrysGrrl

Quote #1: "I never met a magazine mechanic I liked."
Quote #2: "Make sure brain is in gear before engaging mouth!"
Quote #3: "If you can't run with the big dogs, stay on the porch!"

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deadhead
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posted 11-09-2002 09:22 PM     Click Here to See the Profile for deadhead   Click Here to Email deadhead     Edit/Delete Message   Reply w/Quote
I disassembled the carb and ran a bristle from a paint brush through all the idle system passages. I put her back together and she idles just fine. A very interesting change--the idle speed screw is all the way OUT, I set the idle mixture screws at one-and-a-half turns out and the timing at about 8 degrees without the vacuum advance and she idles smooth at about 950 in PARK. Unfortunately, when I hook up the vacuum advance the rpms really climb. I'll have to play with it a while to get a combo that works. I'm driving her now--THANKS MUCH TO YOUSE GUYS--but with the vacuum advance disconnected. Without the vacuum advance she's got zero for acceleration but at least I got to drive her this evening.

I've still got a problem with an off idle stumble. I'm hoping it'll get taken care of when I work out the vacuum advance problem. CRANE makes an adjustable vacuum advance kit I plan to order along with the MSD Cap-A-Dapt. HOWEVER, could the off idle stumble be caused by the fact the idle speed screw is all the way out? I really need to lower the idle rpms a bit more. I have to put her into neutral while approaching a stop or grit my teeth to put enough pressure on the manual drums.

THANKS AGAIN FOR ALL THE TIME AND PATIENCE!!!

My questions will continue, however.

Alex, by the way, I ordered a replacement type CARTER fuel pump. I hadn't planned to actually buy it now since it appears all is as well as it can be. Do you have a differing opinion?

deadhead

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Moneymaker
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posted 11-10-2002 01:34 AM     Click Here to See the Profile for Moneymaker   Click Here to Email Moneymaker     Edit/Delete Message   Reply w/Quote
The stumble can be a combination of no distributor advance and you may not have enough pump shot. Try placing the rod in another hole for more travel.
If it will RPM over 5000 then your pump is OK.

------------------
Alex Denysenko
Co-Administrator and Moderator

NHRA/IHRA/SRA member and licensed Superstock driver
MCA member# 53321
NHRA and IHRA SS/LA National Record Holder '00, '01, & '02
Fleet of FoMoCo products including 88 ASC McLaren Mustang #28
Professional Manwhore
The Barry of BarrysGrrl

Quote #1: "I never met a magazine mechanic I liked."
Quote #2: "Make sure brain is in gear before engaging mouth!"
Quote #3: "If you can't run with the big dogs, stay on the porch!"

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deadhead
Gearhead

Posts: 153
From:
Registered: Sep 2002

posted 11-10-2002 01:15 PM     Click Here to See the Profile for deadhead   Click Here to Email deadhead     Edit/Delete Message   Reply w/Quote
Alex,

I went to the outside hole and hole #4. The stumble is gone, but acceleration is slow. I have no idea what the timing is now, but at least she'll idle in gear. Would a larger volume accelerator pump diaphram help? If so, is one available?

deadhead

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