Help with Balance

[surfsac02]

OK, I need some help. I've done a lot of research on this issue but what I have found has not helped.

The problem that I have is a vibration when the motor is running. What I have is a E6SE-BA 302 which I believe is a 1986 HO. The harmonic and flywheel are the 50oz versions. I just replaced the 20oz flywheel and the vibration got worse.

What can I do to isolate ot correct the issue?

 

[D.Hearne]

Your post isn't clear what you've got or what you've done. You need a 50 oz/in flywheel and balancer. And what may seem to be a balance issue to some can also be a mis-fire or a vacuum leak causing the vibration.

 

[BarnStang]

I think the 20 is a typo for 50, meaning he replaced the 50 with a new 50oz imbalance flywheel...or he could have ment 28...?
Here is a site to help you learn about this issue, but don't take this as written in stone. Google a few other sites and know the facts. D. will also set you straight on this. I say this cause you only have one post. Just because someone posts a link, does not always mean it's a 100% valid info. It's simply a resource for you to use as research to reach a decision or solution. In this case, it was the first link n my Google search. THere are others.
You should have 50oz imbalance front to back on an 86 302 assuming it's stock.
CHeck what D. posted and let us know.
http://www.rowand.net/Shop/Tech/FordFlywheeslAndFlexplates.htm

 

[65ShelbyClone]

Your post isn't clear what you've got or what you've done. You need a 50 oz/in flywheel and balancer. And what may seem to be a balance issue to some can also be a mis-fire or a vacuum leak causing the vibration.

I completely agree. A stock 1986 5.0HO shortblock is a 50oz imbalance engine and should have a 50oz damper and 50oz flywheel.

 

[surfsac02]

Thank yo all for the replies and sorry for the confusion/typo.

Here is what I "think" I have (father did the swap and he's not sure on some of the facts)

* Car is a 1967 coupe
* Trans is from a 72 Mustang that had a standard 302 bolted to it
*We thought the engine was from a 1984 Mustang (the car was totaled and the motor was pulled and put in a crate) but the motor has '22 E6SE BA' stamoed on it. From what i can find, the number tells me it is a 1986 HO 302/5.0
* The harmonic has been replaced with a new solid type that Napa says is for a 1984+ 5.0
* Replacing the harmonic did not correct the vibration
* The flywheel that was on the Trans was replaced with a 157 tooth, 50oz flywheel (KMJ Performance FP302SRHO).
* At this point the vibration got worse
* Firing has been verified
* crank has not been replaced

Vibration is felt throught the car at idle and as RPM increases. Although I am not a "full time" mechanic, those that have looked at it agree that the vibration is NOT normal.

So, research tells me that the crank, harmonic, and flywheel should be the "50oz" version. I believe that flywheel and harmonic are. Other than dropping the pan, are there ways to confirm the crank? Is there something else I should check?

 

[BarnStang]

It would be odd to put a 28oz imbalance crank into an 86 block, but someone could have done this. Has the vibration been there for as long as anyone knows? Since that motor was put in? There is no easy way to tell the imbalance of the crank that I know of. Someone here may be able to tell visually and explain it to you.
It seems unlikely this is the problem. Are you sure its hitting on all 8 cylinders?
If I understand this correctly, this engine was in a car that was wrecked, pulled from the wrecked car, put in a crate, and now that engine is in your car?
Were you able to prove the imbalance of the flywheel you took off? That would be worth finding out. If it IS 28oz, then it may very well be a 28oz crank and need 28oz on both ends...
If it was not pulled apart and rebuilt at any point, then the engine could have sustained some kind of damage internally-I would think that damage would be visually evident from the outside. ANd should have the stock crank. THe unseen damage could be a bent crank from a head on collision. THe crank could be bent just enough to run, but vibrate badly-someone else can confirm this posibility-just a guess on my part. Only way to tell is to tear it apart and have it checked. WHich is why we want to know if this vibration has been there as long as anyone can remember. Or did it start suddenly.

 

[D.Hearne]

E6SE-BA only tells you it's a 1986-up 5.0 block. Only the date code will tell you exactly when it was cast. These blocks were used for several years after 1986.. Be that as it may, I totally agree with BarnStang that it's unlikely it's got a 28 oz crank in it, unless it's a stroker motor or has an aftermarket crank in it. If it was in a collision, the crank could very well be broken in half, that would also cause a vibration.

 

[surfsac02]

Thanks for the replies/suggestions so far. It has been a help.

The vibration has been there since we started it up. The motor and the trans were put together for the first time IN THIS CAR.

The motor was fine from the crash (the damage was not a head on but a inexperienced driver missing a tunr and wrapping the car around a telephone pole).

The motor was fine, with no vibration, when we ran it on a stand (not connected to a trans.

The trans has been in the car for some time and had no vibration from the previous motor.

When we put the motor and the trans together and dropped it into the car, the vibration is there.

I thought the anser was the 28oz vs. 50oz flywheel but that didn't seem to help. When we replaced the flywheel I visually inspected/compared the two parts. The new, 50oz, flywheel had a visually larger weight.

Motor starts easily and runs strong through RPM but vibrates like a son-of-a-gun. There's no knocking, signs of miss-fire, or compression issues (which I think would be signs of a bad crank or other physical damage).

Thanks for the help. Everythign seemed to make sense to replace the flywheel but that did not help. I;'m at my wits end! (not a very long track)

 

[BarnStang]

Before you tear the motor apart, see if you can find a machine shop that can spin that old flexplate. I Googled the part number you posted. It's a C-4 auto right? And tell you what the imbalance really is. If you are going to tear it apart anyway, no need to add the expense, you will get the crank spun anyway to tell the balance.
Generally, the weights "should" be visually the same, and you should be able to tell the difference between 28 and 50 flexplates by looking at them most of the time. I am thinking that if the weight is really smaller on the old flexplate tan the new one, it very well may be a 28oz crank. Still seems a long shot to me. Get the old flexplate spun and let us know what the imbalance is. You could throw parts at this for months and never solve it without some factual data to figure things out.

 

[D.Hearne]

Thanks for the replies/suggestions so far. It has been a help.

The vibration has been there since we started it up. The motor and the trans were put together for the first time IN THIS CAR.

The motor was fine from the crash (the damage was not a head on but a inexperienced driver missing a tunr and wrapping the car around a telephone pole).

The motor was fine, with no vibration, when we ran it on a stand (not connected to a trans.


When we put the motor and the trans together and dropped it into the car, the vibration is there.

Motor starts easily and runs strong through RPM but vibrates like a son-of-a-gun. There's no knocking, signs of miss-fire, or compression issues (which I think would be signs of a bad crank or other physical damage).

I'm betting on a broken crank. 1> it was in a violent collision, it may not have been hit itself, but that doesn't mean the crank or engine didn't sustain damage. I've seen it happen, just the sudden stop can break things that ordinarily would be OK. 2. you ran it on a stand. That was with no load. Different things happen under load & no load. 3. You've got it in the car and running it under a load now (see #2.) Just because a crank is broken doesn't mean it's going to have a knocking sound, missfire or compression issues. I've seen three engines run with broken cranks. Only one had a knocking noise and that was a 4 cylinder Cat diesel. The other two were early 80's 302's with the earliest 50 oz cranks. Pull the oil pan and check it out visually. Use a good work light and a breaker bar on the crank to rotate it back and forth. The crack (separation)can be tough to spot sometimes.

 

[surfsac02]

Thanks Barn' and "D",

Sounds like the best thing for me to do is to put it on the lift and pull it apart (at least the bellhousing and the pan).

I'll let you know what I find.

THANKS!
SAC

 

[surfsac02]

I have worked on this yet but was thinking... Any thoughts on the possibility that the torque converter is bad?

 

[D.Hearne]

Anything's possible. Could be a bad balancer too.