|
By MikeM - 10 Years Ago
|
I have been chasing a vibration in my car since I installed a T-5 trans on my 292. (54 Ford car) Found out that it appears that the input shaft needed to be shortened or it touches the end of the crank. I used a Mummert adapter to install the T-5 on the bell housing. Question is, how much to cut off the input shaft. The thrust bearing is worn pretty good so I am fairly certain the input shaft is hitting. How much do I shave off to get adequate clearance? Can't find a dimension anywhere that I have looked. We believe the trans is out of an '87 Mustang V-8.
Thanks!
|
|
By ponymare - 10 Years Ago
|
|
If the input shaft was hitting the bottom of the crank, it would spin anytime the engine was running, and you couldn't shift into gear. Check the U joints and drive shaft for being warped, also if the trans has many miles, check the output or tail housing bushing.
|
|
By charliemccraney - 10 Years Ago
|
If you actually got it mounted, then it would just barely be touching, if it is touching at all. You should see wear where it was touching. If that is the case, probably 1/16" and bevel the edge and I think you will be ok. When I installed mine, I just pushed the transmission until it touched the crank and used the measurement between the trans case and bellhousing to determine how much to cut off.
You also potentially changed drive line angles and probably had the drive shaft shortened, and those can cause problems if done incorrectly.
Yet another possibility could be that the transmission needs a rebuild.
The transmission will have a tag on it, similar to a rear end, which can be used to id it. If that tag is missing, then there's not really a way to tell what it is
|
|
By MikeM - 10 Years Ago
|
I should have mentioned that the vibration is present between 2000rpm and roughly 5000rpm - doesn't matter if the trans is in gear, clutch in or out, or in neutral. car moving or standing still. It shouldn't be the driveshaft or something inside the trans, except maybe the input shaft, which I will check once I get it out of the car again. The motor had a new thrust bearing installed before the trans went in and in the time since the trans went in and trying to figure this out, we noticed that the thrust bearing was worn - that and reading on here several places about needing to cut the input shaft back, has led me to think I should take a look at cutting mine back. If it is touching, it must be slight as the trans did bolt up OK.
Checked all plugs and wires, firing order, and have gone through the Edelbrock 500cfm carb I installed to try and rule that out. We're now focusing on the trans as the next possibility. This motor ran fine and did not vibrate until I made a couple upgrades - installed the T-5, installed a Mummert Blue Thunder 4bbl intake, and the Edelbrock carb. Not sure related but it also seems to smoke more than it used to through the breather tube - working from easiest to hardest to find the fix.
Thanks.
|
|
By miker - 10 Years Ago
|
|
I used the same method Charlie did, but since the motor was out, I checked the depth with clay before I installed the pilot bearing. In my case, I think it was closer to 1/8. If yours was that tight, I doubt it would shift
|
|
By MikeM - 10 Years Ago
|
|
It shifts fine. The clutch pedal engagement is pretty high (no play when pushing clutch pedal before it releases the clutch). Other than that, trans seems to be working fine. Shifts good in all gears and reverse. Maybe I'm on the wrong path.
|
|
By ponymare - 10 Years Ago
|
|
You need to adjust the clutch so you have about 1inch of free play, running that tight will make the clutch slip, as well as wear the throw out bearing out. Adjusting that might even help with the vibration.
|
|
By Noob - 10 Years Ago
|
I've converted to T-5 in both my 57 bird and 56 Effie... unless Mummert (John) changed his adapter design somehow, it's weird to me how you got an un-shortened input shaft to bolt up "OK" , meaning no gap at the mating surfaces or bent/broken flange ears... 1/16" to 1/8" is a lot, and as aforementioned, rotation engagement would be nearly constant.
But anyway, from your posts, you've got clutch function, the vibration occurs at 2000+ rpm whether in gear rolling or in neutral standing still, the thrust bearing appears worn (how did you determine this, btw?), the pedal engagement is "pretty high", and now the engine is showing some sign of "stress" via greater smoke from the breather.
Noobie guessing here, but is it possible that bolting up an un-shortened input shaft forced the natural crank end play (which gets more generous as engine ages) to a sufficient distance to operate, but has with some use create wear harmonics noticeable at revs higher than idle? Or, since vibration is a symptom of harmonics due to imbalance, is it possible that the Flywheel, clutch disk or pressure are imbalanced due to abnormal wear due to forcing an un-shortened input shaft into place?
I think you'll find the answers once you crack the engine and tranny apart. I doubt it's tranny failure per se, or anything aft from there. Just curious, does it leak oil unusually from the flywheel cover area?
Cheers... Brian
|
|
By MikeM - 10 Years Ago
|
I had the car into a shop a couple years ago (I haven't driven it much since then - just test runs when I try something else) to have the flywheel/clutch assembly balanced. When it was apart he checked the crankshaft end-play and found it to be a little more than normal - not too bad but more than normal. So he did a little investigating and found the thrust bearing worn. He had the trans out of the car and he didn't notice anything odd about how the trans was installed our any clearance issues. My guess is that the input shaft is right up against the end of the crank but not pushing hard on it. Maybe just enough to cause the two to be touching. I did not put the trans in, I had a hot rod shop put it in that has since gone under.
I don't see any unusual leaking under the car - just the drips I get from the rear main seal. Otherwise, nothing more than that. Starts and runs great, just vibrates.
Thanks.
|
|
By Steve - 10 Years Ago
|
MikeM (3/11/2015)
- doesn't matter if the trans is in gear, clutch in or out, or in neutral. car moving or standing still. If the above is true, that it will vibrate in gear, clutch in, car standing still, then it certainly is not the driveshaft or transmission. And if the end of the input shaft was touching the end of the crank it would not shift well, and would grind going into reverse. Sounds like flywheel/clutch imbalance if the engine is running well.
|
|
By Joe-JDC - 10 Years Ago
|
|
I am contemplating installing a T-5 in my T-bird, and from what I have read on John Mummert's site, the driveshaft should be lengthned, not shortened. Any Ford T-5 up to '94 should work as is, and not touch the crankshaft with his spacer kit. Clutch plate should be changed to match the spline of the T-5, but throw out bearing and pressure plate is same. What am I missing about your install? Is it the pilot bearing or the throw out bearing that is worn? Joe-JDC
|
|
By Canadian Hot Rodder - 10 Years Ago
|
|
I had to shorten my input shaft a few thousands when installed my T-5 as it was hitting the crank. Input shafts vary in length Charlie is right, if it was hitting, you would not be able to get the car out gear. If you T-5 is vibrating it may be a bent input shaft, especially if it took out the pilot bearing?
|
|
By MikeM - 10 Years Ago
|
|
Looks like the next step is to pull the trans, replace the thrust bearing, and pilot bearing and check the input shaft. Thanks!
|
|
By Steve - 10 Years Ago
|
If it vibrates with the clutch in and in gear, with the the input shaft not turning, then the input shaft is not a likely candidate.
Along with the other items you are checking, be sure and pull the flywheel and have the clutch/flywheel assembly checked for balance.
|
|
By Jim Rowe - 10 Years Ago
|
I performed the a change from Ford-O-Matic to a top loader 4-speed "big block 4-speed". Input shaft was the same length as a '56 ford 3-speed trans.
I did use a Mummert adapter when I did the T-5 Conversion. I had to build my on rear trans mount. Changed the drive shaft. I had FEW TO CHOOSE FROM.
Now I had Vibration ................. Took the shaft to a drive line shop and had it straightened. Viola vibration gone.
However in your case even though the flywheel and clutch were "balanced" This needs to be done as a unit. Both together, then they will be marked with an index mark. You must have both the clutch cover and the flywheel assembled "index marks" coming together mark to mark.
You mentioned the vibration was apparent when the engine was revved while in neutral and sitting still. I would check this before removing any of the input shaft on the tranny. You can check this by removing the inspection cover on the bell housing and check to see if the clutch and flywheel were installed "indexed".
Good luck!
Jim
|
|
By MikeM - 10 Years Ago
|
|
Will do. They were balanced as a unit because of the vibration, and then re-installed - no change, still had the vibration. I assumed they were installed correctly but I will check. Thanks.
|
|
By ponymare - 10 Years Ago
|
|
,Just wondering here, we pulled the heads from a 330 truck engine a few weeks ago to grind the valves. The pistons on the right bank were different than on the left bank. So just wondering if your engine may have pistons from an unmatched set, maybe even a forged piston in the bunch.
|
|
By Joe-JDC - 10 Years Ago
|
|
A quick check would be to remove the transmission, and throw out bearing, and start the engine and see if it still vibrates at low speeds. The pressure plate should hold the clutch disc in place for this test if it is assembled correctly. That would remove the transmission, drive shaft, and u-joints from the equasion, even though you say it vibrates in neutral. Joe-JDC
|