Brought to you in part by:

Great deals on auto restoration supplies!

.


JC Whitney clearance center!

  Mustangsandmore Forums
  '64 1/2 to '73 -- The Classic Mustang
  bad vibrations

Post New Topic  Post A Reply
profile | register | preferences | faq | search

UBBFriend: Email This Page to Someone! next newest topic | next oldest topic
Author Topic:   bad vibrations
indyphil
Gearhead

Posts: 2354
From: Senoia, G.A. USA
Registered: Jul 2002

posted 09-29-2002 03:50 PM     Click Here to See the Profile for indyphil   Click Here to Email indyphil     Edit/Delete Message   Reply w/Quote
Im not picking up good vibrations today...
took the car out for a ride, testing the brakes out (see other post ) and she started vibrating on acceleration. The only other time she did this was when i had the old points distributor and had the dwell set to low.

I have been over my ignition system which is all new with a pertronix ignitor. Is there a way to test the pertronix kit without re-installing my old stuff? The dwell meter says im getting 30 degrees of dwell which seems healthy.

I was thinking it might be a carb problem, but I dont really know much about carbs. I had to set the mixture screws a while ago, And i did all the choke and speed settings. Is there something on these 2 barrels that can screw up? the little accelerator pump still squirts, what else could be wrong?

Anyway it shakes when i pull away. The idle is fine and when shes moving it cruises ok, but on accleration it shakes and hesitates.

any ideas would be appreciated!!

------------------
'68 coupe 289 2V
CAT engine performance engineer

IP: Logged

indyphil
Gearhead

Posts: 2354
From: Senoia, G.A. USA
Registered: Jul 2002

posted 09-29-2002 05:53 PM     Click Here to See the Profile for indyphil   Click Here to Email indyphil     Edit/Delete Message   Reply w/Quote
I have a theory, see what you think.
When I replaced the fuel sender unit the tank was almost empty and what fuel was left was full of rusty flakes. I didnt fully flush the tank out. The new sender unit had a screen on it but it didnt look very good. Maybe a particle has made it into some kind of secondary jet on one side of my 2 barrel. Then when i accelerate its lean on that side causing the vibration?

what do you think? anybody had dirt cause problems like this? i do have an inline filter at the carb but the fuel is probably very dirty. It all started while i was cornering and seems worse when i go round corners and accelerate at the same time.

IP: Logged

indyphil
Gearhead

Posts: 2354
From: Senoia, G.A. USA
Registered: Jul 2002

posted 09-29-2002 06:23 PM     Click Here to See the Profile for indyphil   Click Here to Email indyphil     Edit/Delete Message   Reply w/Quote
Another question
When buying another carb, (I have been thinking about buying a new one instead of working on the old one) Do I buy an electric choke seeing as i don't have a cable operated one today? I mean the one I have senses temperature from the heater hose, and has a little pipe that runs down to the cast iron manifolds. If I install say an edelbrock carb with electric choke how does it work? also why do those carbs say I need a linkage for a ford auto transmission? I have a C-4 but my car only has a vacuum line running to the tranny, there is no linkage or cable. Whats that all about?

any help on any of the above subjects would be greatly appreciated.

Phil

------------------
'68 coupe 289 2V
CAT engine performance engineer

IP: Logged

SteveLaRiviere
Administrator

Posts: 42859
From: Saco, Maine
Registered: May 99

posted 09-29-2002 06:44 PM     Click Here to See the Profile for SteveLaRiviere   Click Here to Email SteveLaRiviere     Edit/Delete Message   Reply w/Quote
Yes, you could have pick up a rust flake or dirt. The filter is supposed to stop that, but you know how that goes sometimes.

Stumbling while cornering suggests a low float level, though.

Electric chokes are cool. You just hook them to a 12v keyed source under your hood, or run a wire to an accessory circuit under the dash.

The Ford linkage refers to the passing gear kick down rod for your transmission. If your car doesn't have one now, it used to.

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

IP: Logged

indyphil
Gearhead

Posts: 2354
From: Senoia, G.A. USA
Registered: Jul 2002

posted 09-30-2002 09:07 AM     Click Here to See the Profile for indyphil   Click Here to Email indyphil     Edit/Delete Message   Reply w/Quote
Thanks steve,
I found that there is a cable attached to the throttle linkage but its no-where near the carb. When i took the old 2 barrel off A lot of rusty gas came out. I guess the inline filter didnt do the job.

I have bought a new carb (edelbrock 4 barrel 600CFM vac secondarys) and dont want it to suffer the same fate. I need a good inline filter preferably one that i can see into. I bought the performer intake not the RPM to go with it. It has electric choke and I can see now that it is going to be easy to fit up.

IP: Logged

Pierre
Gearhead

Posts: 541
From: Near Paris, France
Registered: Apr 2002

posted 09-30-2002 09:08 AM     Click Here to See the Profile for Pierre   Click Here to Email Pierre     Edit/Delete Message   Reply w/Quote
Indyphil,

I fought a similar problem for years changed the carb, distributor, I even changed the original damper for a 350$ fluidamper ....... Nothing !!

Your carb theory, although possible, is highly unlikely. I would keep focussing on the ignition system especially all elements that are not new (coil cutting out under load, wires with bad connections,....). This is were my problems (several) were . Check-out your spark plugs, they could give you some pointers

IP: Logged

indyphil
Gearhead

Posts: 2354
From: Senoia, G.A. USA
Registered: Jul 2002

posted 09-30-2002 09:14 AM     Click Here to See the Profile for indyphil   Click Here to Email indyphil     Edit/Delete Message   Reply w/Quote
Sorry to hear that you had such a big problem for so long Pierre. We will see what happens with my new carb, when i took the old one off I did find a lot of dirt in there. I did suspect the ignition myself but everything seems to check out.

Im looking for easy ways to flush out the fuel tank to try to avoid this again (if dirt was the cause!)

IP: Logged

indyphil
Gearhead

Posts: 2354
From: Senoia, G.A. USA
Registered: Jul 2002

posted 10-04-2002 05:18 PM     Click Here to See the Profile for indyphil   Click Here to Email indyphil     Edit/Delete Message   Reply w/Quote
OK, new edelbrock 600CFM carb, and performer intake, a lot more power

Only slightly less vibration probably just running a little richer that helps a bit

could it be my pertroix system?
I have a new flame thrower coil, new 7mm plug wires, new pertronix kit (gap checked).
new distributor cap, but not a new rotor arm.

Could it be cross fire with the stock cap? why would it suddenly start like that while driving along? Over the weekend I will start testing all the ignition stuff and checking plugs and wires. It seems to smooth out just above idle, but at idle and under load it rumbles and shakes. the timing had checked out with the strobe before so I dont suspect timing. My ignition leads look like a birds-nest and im worried that they are crossfiring or something.

IP: Logged

Pierre
Gearhead

Posts: 541
From: Near Paris, France
Registered: Apr 2002

posted 10-05-2002 06:04 AM     Click Here to See the Profile for Pierre   Click Here to Email Pierre     Edit/Delete Message   Reply w/Quote
Forgive me if some of this are things we have already gone through but based on your description this is what I would check:

Physical problem: bad motor/trans mounts, damper's health (rubber may have suddenly broken which would be more noticeable under load) , loss of a weight on the rotating parts (ie: flywheel, clutch,......)

Electrical: like I said before this is morelikely your problem. Here is what I did to track down my ignition problems: I used my timing light, opened it connected the input of a scope (you can rent on for cheap) to the input signal of the timing light (you may want to search on the timing light electronic board where the signal is stronger & easier to read on the scope). Then use this set up to read all wires in various location & RPM/load context. Sounds bad but it allowed me to track my problem a lot more easily.

Hope that helps

IP: Logged

Pierre
Gearhead

Posts: 541
From: Near Paris, France
Registered: Apr 2002

posted 10-05-2002 06:10 AM     Click Here to See the Profile for Pierre   Click Here to Email Pierre     Edit/Delete Message   Reply w/Quote
Here is a site that has a very good diagnostic chart. I know this is not from Ford & hope you will forgive me

http://www.tracyvette.com/vibrationdiagnosis.html

IP: Logged

johnmustang
Gearhead

Posts: 5818
From: British Columbia , Canada
Registered: Nov 2001

posted 10-05-2002 10:07 AM     Click Here to See the Profile for johnmustang   Click Here to Email johnmustang     Edit/Delete Message   Reply w/Quote
If the crap in your tank has caused you so many problems , why not bite the bullit , and , just get a new tank and install it , they are not expensive and it will solve your problem. I would then disconnect your fuel line from your carb , remove any fuel filters and flush all your lines with gas from your new gas tank.

JOHN

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

IP: Logged

indyphil
Gearhead

Posts: 2354
From: Senoia, G.A. USA
Registered: Jul 2002

posted 10-05-2002 02:47 PM     Click Here to See the Profile for indyphil   Click Here to Email indyphil     Edit/Delete Message   Reply w/Quote
OK, i have tracked the problem down to the misfire of cylinder number 7. Only number 7 has a problem (i did that trick where you pull a lead off one at a time and see if the RPM changes)
All the others seem fine. There is spark going to the plug because when you put the lead back in you can see it sparking away like crazy. I need to check the condition of the spark plug (make sure it isnt shorting across some debris or is gapped wrong) then I shall do a compression test. I am suspecting my head gaskets because I have seen traces of oil in my coolant. So it could be time for a top end overhaul. Yuck... I will keep you guys informed. I think that the dirty fuel wasnt the root cause, but a new tank would still be a good idea.

------------------
'68 coupe 289 2V
CAT engine performance engineer

IP: Logged

indyphil
Gearhead

Posts: 2354
From: Senoia, G.A. USA
Registered: Jul 2002

posted 10-06-2002 12:54 PM     Click Here to See the Profile for indyphil   Click Here to Email indyphil     Edit/Delete Message   Reply w/Quote
Idle is fixed now. #7 was misfiring because stupid me thought it would be a good idea to re-arrange where the PCV line goes. I put in the manifold boss on #7.

While at idle the car seems ok (in park) but when i put it in drive it drops speed and becomes rougher. Then when i drive it I still get the same vibrations/misfiring I did last week when trying to accelerate. I cant seem to find which cylinder is misfiring though.

IP: Logged

indyphil
Gearhead

Posts: 2354
From: Senoia, G.A. USA
Registered: Jul 2002

posted 10-06-2002 04:50 PM     Click Here to See the Profile for indyphil   Click Here to Email indyphil     Edit/Delete Message   Reply w/Quote
OK.... PERTRONIX.... $%@[email protected]%#[email protected]$%#%
Put my old points back in, problem solved.
The pertronix kit had punked out on me after a grand total of about 3 short rides.

Now im stuck with a tired out set of points but at least it runs and runs smooth. In fact with the new carb and intake it runs REAL good. So who else had a pertronix system ^#%$ up like that? I even used THEIR coil. its not like i was over loading it either. I need something more reliable than the ignitor, is the ignitor 2 any better? Can i get my money back for the POS that just cost me so much @$$ pain? we shall see.

Just an update for ya.

IP: Logged

All times are ET (US)

next newest topic | next oldest topic

Administrative Options: Close Topic | Archive/Move | Delete Topic
Post New Topic  Post A Reply
Hop to:

Contact Us | Mustangsandmore Front Page

Copyright 2005, Steve LaRiviere. All Rights Reserved.


Ultimate Bulletin Board 5.47d

Amazon Honor System Click Here to Pay Learn More

[Build a free Mustangsandmore.ws Home Page!]

[Posting Pictures]

[About M&M][Acronyms][Calendar][Chat][Classifieds] [Members' Pics]

[M&M Conventions] [M&M Mug Shots]

[ Mustangsandmore.com Bookstore] [ Smokin' Fords] [Tech Articles]