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Author Topic:   Motor has a miss?
66bluefb
Gearhead

Posts: 456
From: Okla.City,Okla.
Registered: May 2002

posted 11-19-2002 07:13 PM     Click Here to See the Profile for 66bluefb   Click Here to Email 66bluefb     Edit/Delete Message   Reply w/Quote
I don `t know what's wrong with my motor. I took my 66-289 heads off my 86-302 to redrill my steam holes so my car wouldn't run hot. I put it back together and let it run for 20 minutes then I changed the oil. I then drove it around the block. At the end of the street I lit it up in first gear and it ran good. Then when I pulled in the drive way I could tell it was cutting out a little. I thought it might be my spark plug wires since I was running 7 mm so I went and bought some 8 mm wires and it didn't help. It still runs good but it just has a little miss and it bogs down a little when I take off in 1st gear. I also retimed it. Everything on the motor,electrical,and fuel except for my carb is only 3 months old. The carb is 2 years old. Any help would be appreciated.Thanks,Tony

------------------
http://ourworld.cs.com/blagintony/myhomepage/auto.html
86-302 HO bored .030 over crank .010 under
B-303 cam ,harland sharp roller rockers
performer rpm intake,85 duraspark ignition, 625 carter
66-289 heads, ported with 160-194 valves, 3 angle valve job
4 speed toploader
pony seats

[This message has been edited by 66bluefb (edited 11-19-2002).]

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RADRIDE
Gearhead

Posts: 243
From: Va.Beach, Va.
Registered: Aug 2002

posted 11-19-2002 07:23 PM     Click Here to See the Profile for RADRIDE   Click Here to Email RADRIDE     Edit/Delete Message   Reply w/Quote
Just an uneducated guess, but since you just had heads off maybe a valve got adjusted to tight and your loosing compression.

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V8 Thumper
Gearhead

Posts: 3529
From: Orange, Ca. United States of America
Registered: Dec 2001

posted 11-19-2002 08:34 PM     Click Here to See the Profile for V8 Thumper   Click Here to Email V8 Thumper     Edit/Delete Message   Reply w/Quote
Is the miss consistent across the rpm range?

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66bluefb
Gearhead

Posts: 456
From: Okla.City,Okla.
Registered: May 2002

posted 11-19-2002 09:49 PM     Click Here to See the Profile for 66bluefb   Click Here to Email 66bluefb     Edit/Delete Message   Reply w/Quote
Sorry I took so long to answer. Yes it is consistent across the rpm range.I also turned my roller rockers no more than 1/2 turn after I felt pressure.

------------------
http://ourworld.cs.com/blagintony/myhomepage/auto.html
86-302 HO bored .030 over crank .010 under
B-303 cam ,harland sharp roller rockers
performer rpm intake, 625 carter
66-289 heads, ported with 160-194 valves, 3 angle valve job
4 speed toploader
pony seats

[This message has been edited by 66bluefb (edited 11-19-2002).]

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V8 Thumper
Gearhead

Posts: 3529
From: Orange, Ca. United States of America
Registered: Dec 2001

posted 11-19-2002 09:55 PM     Click Here to See the Profile for V8 Thumper   Click Here to Email V8 Thumper     Edit/Delete Message   Reply w/Quote
Pull all 8 plugs and inspect closely. One should look much darker than the other 7, it may even look moist. That could narrow your search to which cylinder that isn't firing. Try that, and post the results

------------------
1965 GT coupe, 333ci aluminum headed/solid cammed stroker, four speed, 3.70:1 9"

All Blue Oval, no blue bottle
http://mustangsandmore.50megs.com/V8Thumper.html

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66bluefb
Gearhead

Posts: 456
From: Okla.City,Okla.
Registered: May 2002

posted 11-19-2002 10:02 PM     Click Here to See the Profile for 66bluefb   Click Here to Email 66bluefb     Edit/Delete Message   Reply w/Quote
V8 Thumper,I pulled my plugs when I took the heads off and my # 1 looked a little wet like maybe gas. I don`t think it was oil. So I put them back in and like I said it ran fine till I got on it.I pulled the plugs back out Sunday and washed them with gasoline and a tooth brush.A guy at work told me today that washing them with gasoline screwed them up. Is that right?Tony

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V8 Thumper
Gearhead

Posts: 3529
From: Orange, Ca. United States of America
Registered: Dec 2001

posted 11-19-2002 10:16 PM     Click Here to See the Profile for V8 Thumper   Click Here to Email V8 Thumper     Edit/Delete Message   Reply w/Quote
Gasoline won't hurt them.
Even though they've been run a short while, they will show exactally how each cylinder is hitting by the deposits(color), it's called 'reading' the plugs. What you're looking for is one that is obviously way different than the rest, and is most likely to be dark. An optimum read would look tan to light brown, too lean would be light grey to white, too rich is dark and sooty. Whichever cylinder isn't firing would still have an air/fuel charge being pumped through it, just isn't having the oportunity to fire for a reason we'll soon find out. Even though you cleaned/checked them before you fired it up, check them again. One of them should lead us in the right direction

------------------
1965 GT coupe, 333ci aluminum headed/solid cammed stroker, four speed, 3.70:1 9"

All Blue Oval, no blue bottle
http://mustangsandmore.50megs.com/V8Thumper.html

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66bluefb
Gearhead

Posts: 456
From: Okla.City,Okla.
Registered: May 2002

posted 11-19-2002 10:19 PM     Click Here to See the Profile for 66bluefb   Click Here to Email 66bluefb     Edit/Delete Message   Reply w/Quote
Thanks, I`LL do it Sat.morning.Tony

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soaring
Gearhead

Posts: 116
From: New Mexico
Registered: Nov 2002

posted 11-20-2002 05:58 AM     Click Here to See the Profile for soaring   Click Here to Email soaring     Edit/Delete Message   Reply w/Quote
start with elictrical, then go to fuel. All systems aer slightly differet, but missing generally starts with the electrical system. When that is all set up properly, then the fuel slow is the next culprit. More description is needed to help you determine your problem. Give us more facts.

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69 Sportsroof
Gearhead

Posts: 1214
From: Valley, Alabama, USA
Registered: Mar 2002

posted 11-20-2002 10:42 AM     Click Here to See the Profile for 69 Sportsroof   Click Here to Email 69 Sportsroof     Edit/Delete Message   Reply w/Quote
Did you use new intake gaskets? Had a miss like that happen one time and it was caused by a vacuum leak from underneath the intake. Long shot but definately a consideration. If you have a push on style oil cap, it will make a short hiss sound when romoved while the engine is running, much like a can of tennis balls when first opened. When you find the odd plug, connect a spark tester to the wire and see if it's working. If it's ok then you've eliminated the electicals.

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69 Sportsroof
Gearhead

Posts: 1214
From: Valley, Alabama, USA
Registered: Mar 2002

posted 11-20-2002 10:48 AM     Click Here to See the Profile for 69 Sportsroof   Click Here to Email 69 Sportsroof     Edit/Delete Message   Reply w/Quote
Did you use new intake gaskets? A miss like this can be caused by a vacuum leak from underneath the intake. The plug will have a blueish tint to it due to the oil vapor being sucked into the cylinder and it will not allow the plug to fire. You can connect an inductive timing light or tach to each cylinder to see which plugs are/aren't firing. Once found, connect a spark tester to the bad wire and see if it fires then. If it does, you've eliminated any electrical problems and should start looking for mechanical failure.

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69 Sportsroof
Gearhead

Posts: 1214
From: Valley, Alabama, USA
Registered: Mar 2002

posted 11-20-2002 02:07 PM     Click Here to See the Profile for 69 Sportsroof   Click Here to Email 69 Sportsroof     Edit/Delete Message   Reply w/Quote
Well, it didn't show up the first time and I couldn't remember the exact way I worded it....

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66bluefb
Gearhead

Posts: 456
From: Okla.City,Okla.
Registered: May 2002

posted 11-20-2002 06:33 PM     Click Here to See the Profile for 66bluefb   Click Here to Email 66bluefb     Edit/Delete Message   Reply w/Quote
I put new wires on it Monday So I wouldn`t think it was that since I`ve had two sets of wires on it.I did use a new intake gasket.A guy at work told me to re tightin the intake bolts.I`ll also listen for a hissing sound out of my oil cap.I`ll do that tonight and let you all know if it helped.Thanks,Tony

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66bluefb
Gearhead

Posts: 456
From: Okla.City,Okla.
Registered: May 2002

posted 11-20-2002 08:19 PM     Click Here to See the Profile for 66bluefb   Click Here to Email 66bluefb     Edit/Delete Message   Reply w/Quote
I went out to check my intake bolts and the first one I checked in the middle was loose.I`ll be damn. I went ahead and re tighten the rest of them a then drove it. Runs a lot better. The miss is gone. Still has a little bogg when I take off in first gear but that is my timing. Do you think that I need to put a new intake gasket on the motor? Thanks for all your replies, Tony

------------------
http://ourworld.cs.com/blagintony/myhomepage/auto.html
86-302 HO bored .030 over crank .010 under
B-303 cam ,harland sharp roller rockers
performer rpm intake, 625 carter
66-289 heads, ported with 160-194 valves, 3 angle valve job
4 speed toploader
pony seats

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69 Sportsroof
Gearhead

Posts: 1214
From: Valley, Alabama, USA
Registered: Mar 2002

posted 11-20-2002 10:39 PM     Click Here to See the Profile for 69 Sportsroof   Click Here to Email 69 Sportsroof     Edit/Delete Message   Reply w/Quote
While the engine is cold, retouque the intake following the proper sequence and using the correct torque settings. If you're guessing about torque values you aren't doing yourself any favors. That can wreak havoc on an aluminum intake.....

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soaring
Gearhead

Posts: 116
From: New Mexico
Registered: Nov 2002

posted 11-21-2002 02:10 AM     Click Here to See the Profile for soaring   Click Here to Email soaring     Edit/Delete Message   Reply w/Quote
Congrats on getting out the miss. Now that it bogs when you get on it, it can be two things. Timing, and carburetor setting. Start with the timing, then if that doesn't get rid of the bog, check your timing belt and replace if you haven't done that in awhile. Also, how long has the distributor been on the motor?

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69 Sportsroof
Gearhead

Posts: 1214
From: Valley, Alabama, USA
Registered: Mar 2002

posted 11-21-2002 10:13 AM     Click Here to See the Profile for 69 Sportsroof   Click Here to Email 69 Sportsroof     Edit/Delete Message   Reply w/Quote
Timing belt? Did I miss something?

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66bluefb
Gearhead

Posts: 456
From: Okla.City,Okla.
Registered: May 2002

posted 11-21-2002 07:33 PM     Click Here to See the Profile for 66bluefb   Click Here to Email 66bluefb     Edit/Delete Message   Reply w/Quote
Soaring,Its pretty cool talking to some one from Japan. My dist. is only 3 months old,I`m pretty sure its my timing.I have a 66 mustang with a 86-302 in it. Well it was costing me a small fortune to build the motor and plus buying the stuff to fit in my 66 like clutch bracket, new clutch kit,85 duraspark ignition and the list goes on.I was just running out of money.You know when you tell your wife its going to cost 2.000 to built a 302 and it cost some where like 2.500 I went ahead and bought a 50 oz hormonic balancer for 75.00 instead of the 175.00 one from NPD thats will let me use my radiator.So my timing mark is where the water pump outlet is.I`m going to buy a radiator that has the outlet on the drivers side next spring so I can time it with a light.Until then I just have to time it by ear.Thanks,Tony

------------------
http://ourworld.cs.com/blagintony/myhomepage/auto.html
86-302 HO bored .030 over crank .010 under
B-303 cam ,harland sharp roller rockers
performer rpm intake, 625 carter
66-289 heads, ported with 160-194 valves, 3 angle valve job
4 speed toploader
pony seats

IP: Logged

soaring
Gearhead

Posts: 116
From: New Mexico
Registered: Nov 2002

posted 11-21-2002 08:22 PM     Click Here to See the Profile for soaring   Click Here to Email soaring     Edit/Delete Message   Reply w/Quote
quote:
Originally posted by 66bluefb:
I don `t know what's wrong with my motor. I took my 66-289 heads off my 86-302 to redrill my steam holes so my car wouldn't run hot. I put it back together and let it run for 20 minutes then I changed the oil. I then drove it around the block. At the end of the street I lit it up in first gear and it ran good. Then when I pulled in the drive way I could tell it was cutting out a little. I thought it might be my spark plug wires since I was running 7 mm so I went and bought some 8 mm wires and it didn't help. It still runs good but it just has a little miss and it bogs down a little when I take off in 1st gear. I also retimed it. Everything on the motor,electrical,and fuel except for my carb is only 3 months old. The carb is 2 years old. Any help would be appreciated.Thanks,Tony


Be sure you regap the points after the timing is set. That is, if you have points. If the timing change doesn't help, after adjusting your carb, you might consider changing the jets in the carb.

------------------
http://www.angelfire.com/musicals/glenwren/left.JPG

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69 Sportsroof
Gearhead

Posts: 1214
From: Valley, Alabama, USA
Registered: Mar 2002

posted 11-21-2002 09:52 PM     Click Here to See the Profile for 69 Sportsroof   Click Here to Email 69 Sportsroof     Edit/Delete Message   Reply w/Quote
quote:
Originally posted by 66bluefb:
So my timing mark is where the water pump outlet is.I`m going to buy a radiator that has the outlet on the drivers side next spring so I can time it with a light.

You can locate TDC anywhere you want on your balancer. You just need a pointer, a piston stop and timing tape.

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66bluefb
Gearhead

Posts: 456
From: Okla.City,Okla.
Registered: May 2002

posted 11-21-2002 10:05 PM     Click Here to See the Profile for 66bluefb   Click Here to Email 66bluefb     Edit/Delete Message   Reply w/Quote
69 Sportsroof,I have a pointer off my 289 I could use. Where would I get a tape and what is a piston stop?Thanks,Tony69

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senzstang
Gearhead

Posts: 122
From: perry, oh, usa
Registered: May 2002

posted 11-22-2002 07:46 AM     Click Here to See the Profile for senzstang   Click Here to Email senzstang     Edit/Delete Message   Reply w/Quote
I'm sure Summit sells the timing tape. I don't know about the piston stop.

Phil

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69 Sportsroof
Gearhead

Posts: 1214
From: Valley, Alabama, USA
Registered: Mar 2002

posted 11-22-2002 08:08 AM     Click Here to See the Profile for 69 Sportsroof   Click Here to Email 69 Sportsroof     Edit/Delete Message   Reply w/Quote
quote:
Originally posted by 66bluefb:
69 Sportsroof,I have a pointer off my 289 I could use. Where would I get a tape and what is a piston stop?Thanks,Tony69

A piston stop screws into your spark plug hole and extends down into the cyliner and inch or so. I got mine from Napa. First thing you do is disconnect your neg battery cable, then remove all of your spark plugs and install the piston stop in the number one spark plug hole. Install your pointer and using a socket, slowly turn the crank shaft until the number one piston contacts the piston stop. Mark the balancer where it lines up with the pointer with a scribe or a dot of paint. Now slowly turn the crank in the opposite direction until the piston contacts the stop again. Mark the crank at the pointer. TDC is half way between the two marks.

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soaring
Gearhead

Posts: 116
From: New Mexico
Registered: Nov 2002

posted 11-22-2002 06:23 PM     Click Here to See the Profile for soaring   Click Here to Email soaring     Edit/Delete Message   Reply w/Quote
quote:
Originally posted by 69 Sportsroof:
A piston stop screws into your spark plug hole and extends down into the cyliner and inch or so. I got mine from Napa. First thing you do is [b]disconnect your neg battery cable, then remove all of your spark plugs and install the piston stop in the number one spark plug hole. Install your pointer and using a socket, slowly turn the crank shaft until the number one piston contacts the piston stop. Mark the balancer where it lines up with the pointer with a scribe or a dot of paint. Now slowly turn the crank in the opposite direction until the piston contacts the stop again. Mark the crank at the pointer. TDC is half way between the two marks.[/B]


I was assuming the pointer was there already. Although the bogging is most likely the timing, the carb might need adjusting as well.

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66bluefb
Gearhead

Posts: 456
From: Okla.City,Okla.
Registered: May 2002

posted 11-22-2002 06:31 PM     Click Here to See the Profile for 66bluefb   Click Here to Email 66bluefb     Edit/Delete Message   Reply w/Quote
Thanks guys,That solves my timing mark problem and its cheaper than buying a new balancer.Tony

------------------
http://ourworld.cs.com/blagintony/myhomepage/auto.html
86-302 HO bored .030 over crank .010 under
B-303 cam ,harland sharp roller rockers
performer rpm intake, 625 carter
66-289 heads, ported with 160-194 valves, 3 angle valve job
4 speed toploader
pony seats

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