302 vibration <HR style="COLOR: #999999" SIZE=1><!-- / icon and title --><!-- message --> I recently rebuilt and installed a ford 302 in my son's 66 Mustang. I now have a bad vibration between 2000 and 2800 rpm. It has a C-4 auto. trans. We pulled the engine back out and had the balance rechecked, it was OK. We tried new flex plate and torque converter, put the original motor mounts back on, put the original dampner back on, pulled the trans. and ran it with just the bellhousing on it (no vibration felt at that point), replaced the flexplate, ran it without the belts. It originally had a 289 in it and did not have this problem. Has anyone heard of the trans. front pump causing a vibration like this? Any help would be greatly appreciated!! Mike Merry Fordranchman <!-- / message -->
What year 302? Later ones have different external balance. Up to the early 80s used 28 in-oz imbalance; later ones used 50 in-oz imbalance.
To run the later 302 with 50oz weight flexplate with the early small bellhousing tranny, you need a 157 tooth flexplate with 50oz weight. Ford never made these but they are avail from most speed shops or Summit or Jegs.
My own further question... I have a '89 model 5.0L / AOD out of a full size Ford Car in my F-100. It's all the original parts combination except I exchanged the torq converter to 2000rpm aftermarket unit. I have the same vibration issue. Is the converter supposed to be balaced to the flex plate? Is it supposed to be independently balanced? The drive shaft is all new, phased and balanced.
yeah, everything is balanced with 28 oz. It is a 72 motor. The flexplate is new, and it did it with the old one.
Make sure the converter is seated all the way into the trans and that the drain plug is lined up with the correct hole in the flexplate. The front pump can cause a vibration if the bushing is worn out. But you would see brass/copper in the filter or pan. ____________________________________________ Who was that masked man?
bad memory;s Happen to me, pulled the motor trans out and changed to the stock flexplate and balancer to the block
yeah, it's all out of my old 72 F100. It has trw flat tops, scat rods, new dampner, new flex plate, new torque converter. Are car bell housings and truck ones the same? As I said we took the motor apart again and had it rechecked. The machinist demonstrated it to me and he is just as puzzled.
72 302, same as the one I'm building. The new balancer is 28oz and were sure the flexplate is 28oz. Both are, new and old. When you pulled the motor back out, did you check the crank? A 28oz crank will have either 2M or 2MA cast on one of the counterweights. Just pop the oil pan and take a look. If its 50oz it will have 2MAE cast on it. Maybe your machinist switched em by accident, it was replaced?
I remember that it had the 2M marking on it, because I was trying to make sure what crank I had. I have some 289's and 302's laying around along with my big block parts. The block is also a 72 by the casting marks. I don't have any engines in the shop newer than 79 and that one is still together so I know nothing got swapped out of that one. Believe me, I do appreciate all of the responses that you guys have given me, but so far I have all of those bases covered. This thing is really wierd!!! The bell housing that I am using is the one from the 289, could it be that the depth is different from what is needed on a 302? Thanks for all of your help. I am going out into the garage now and rebush a different front pump from another trans. and try it yet again. I am not one to give up!! Fordranchman
As far as I know, there is no difference in the depth of the bellhousings for a C4. To the best of my knowledge, they are all the same. The only difference in bellhousings I know of is between a manual bellhousing an a manual T5 bellhousing. C6, AOD, FMX, all the other can't change bells and work on 302/289 which leads me to believe there is not difference between them.
The transmission could be a bit off-center. Check the condition of the locating dowels. Check that the pilot in the crank isn't wallowed out.
While you have the trans out again try running the motor without the trans and torque converter. Just bolt the bellhousing on and the starter.
Years ago, I saw a balancer that the inertia ring had come loose and rotated some. If your balancer is neutral balance, this won't help. I don't know how bad your vibration is but it's been my exp. that if it's the flywheel or balancer, it vibrates in neutral. If it has to be moving in gear, you need to look elsewhere. Good luck. From your description I'm sure you've had enough fun with this.
Do you guys read the post? It's not a manual, so there's no pilot bearing. He already ran it sans transmission and felt no vibration.
Already did that. There was no vibration felt with the engine and no trans. We just finished up reinstalling the trans and buzzed it around with open headers ( it's good to live in a rual area ). It felt better with the "new" front pump. So we put the exhaust back on and drove it again and there is definately an improvement. So I might run over to the closest Pick and Pull tomorrow and see if we can find another C-4. Wish me luck!! Fordranchman
He didn't say pilot bearing, I think he's referring to where the convertor seats in the back of the crank. It's somewhat rare but it does happen that the nose of the convertor wallows out the back of the crank - easy to miss if you're not specifically looking for it.
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