Weird 47 vibration solution

[Cecil/WV]

I had a slight clutch chatter in reverse [n my '50 Ford when i first got it running after setting for 26 years, all original. I lived with it. When I lost a piston in Kansas in 2010 and rebuilt the engine, I installed a new clutch ass'y from Fort Wayne Clutch and had a chatter in both directions. I lived with it. I decided I would try to correct it before driving to Lake Tahoe in 2013 so I pulled it apart and checked all the things that you are supposed to check like flywheel runout end play, etc. and found nothing wrong. Looked at the pilot bushing and found a bit of movement on the input shaft. I installed a new roller bearing and another new FWC assembly and the chatter is gone as well as a vibration that I had. I don't know if it was the bearing or the clutch ass'y, but it worked for me for the last 7000 miles or so.

[OLD...BILL]

Originally Posted by JWL

I have another vote for pilot bearing missing or worn or pilot shank on trans. input shaft worn. Neither are fun to fix.

I agree, the only thing I can thing of that will "FIX" it self in rough, when you played the clutch, and then come back with the next change of gears, for your information the ( pilot bearing ) is not shown in the chart /graph layout, green book....copy ? ? .....OLD.....BILL

[Bolts]

Professor, did you say you replaced the rear end and AFTER THAT the vibration started?

[rotorwrench]

I'm a firm believer is thorough inspection of parts before replacement. It's the aircraft mechanic in me. We can't afford to red tag things unless they are beyond service limits. There is also the new parts factor. A bearing that is known to be in good condition is generally a safer bet that an unknown new replacement part. Some replacement parts now days are crap.

If I was checking the clutch & transmission, the first thing would be to shake the shafts for signs of play. No play and quiet rotation are signs of good parts. The flywheel might need resurfaced but those are things that a person can see and check for serviceability. I wouldn't replace a main input shaft unless it was worn out but the input related bearings might need replacing. As much as old Henry gets used, a new ball bearing pilot would be a good idea. The old bushings are OK if you don't drive much but the ball bearing will keep alignment better until the bearing goes bad. The ball type pilot bearings will generally last the life of the clutch disk if you drive it regularly.

Parts at the back end from the transmission main output shaft to the wheels will make their noise or vibrate whether you disengage the clutch or not in most cases. Most of those old drive shaft center bearings are probably crusty & rusty. There aren't a lot of choices about where you get a new one either. U-joints are a basic part and the OEM ones are pretty tough. Here again, if it ain't broke, don't fix it. They don't have same type needle bearings like the later stuff does. They generally just wear out the spider, bushing, & ring assembly.

I think I'd start at the front and check all the clutch & main input stuff first. I consider the counter shaft (cluster gear) as input stuff since it it rotated by the engine and slows up pretty quick when you disengage the clutch disk especially if the trans is shifted to neutral. If the trans is in high gear the input will coast with the output. The trans output shaft keeps rotating as long as the car is coasting until it stops completely, whether it is in neutral or not.

[Old Henry]

Originally Posted by OLD...BILL

I agree, the only thing I can thing of that will "FIX" it self in rough, when you played the clutch, and then come back with the next change of gears, for your information the ( pilot bearing ) is not shown in the chart /graph layout, green book....copy ? ? .....OLD.....BILL

So, I guess I don't know what a pilot bearing is if it's not on any of the diagrams I posted. What is it? A lot have mentioned it.

[Ross F-1]

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It is in the flywheel, or in the end of the crankshaft on some engines, and supports the front end of the input shaft.

[Old Henry]

Originally Posted by Bolts

Professor, did you say you replaced the rear end and AFTER THAT the vibration started?

It was in that sequence but not proximate in time.
I replaced the rear end a year and 17,000 miles before the vibration started.

[34 FORDOR]

I would also go with the pilot bush / bearing and maybe the clutch disc especially if it is one the currently produced ones, some of them are rubbish. I was about to install a new one , after removing the packaging I noticed the center hub was loose,( this would get worse with wear )which allows the outer plate to move off center, which would change every time you used the clutch and cause a vibration. It will join my other repro crap items, rear end gears, trans gears, bearings etc.

[Old Henry]

Sure appreciate everyone's input. I hang on your every word and suggestion. I am not looking forward to this project but have to do it and hopefully will be able to solve this annoying problem with one R&R only. That's my goal.

[Talkwrench]

Bugger .. Bugger, think that brush has tared me! Coming home from a cruise today I was sitting on about 65 -68 mph sweet as...and then vibration started.. like it dropped a cyl or two, or blown a manifold gasket I was checking all gauges while it was happening, all OK vacuum fine, heads well under temp etc. I immediately thought of you Old Henry.. I slowed down a bit flicked the clutch in a few times and it halved the vibration. When I got off the FWY everything seemed normal. Nothing wrong under the car.. So I guess we'll see what happens....?

[Old Henry]

Originally Posted by Talkwrench

Bugger .. Bugger, think that brush has tared me! Coming home from a cruise today I was sitting on about 65 -68 mph sweet as...and then vibration started.. like it dropped a cyl or two, or blown a manifold gasket I was checking all gauges while it was happening, all OK vacuum fine, heads well under temp etc. I immediately thought of you Old Henry.. I slowed down a bit flicked the clutch in a few times and it halved the vibration. When I got off the FWY everything seemed normal. Nothing wrong under the car.. So I guess we'll see what happens....?

Glad my weird solution worked for you. I know it's only a temporary fix but sure is nice to at least be able to get rid of the vibration when I want to.

Thanks for your story.

[Bolts]

Professor, I am offering this advice based on your desire to hear what others think is needed.
You said earlier the engine always had vibration and the clutch chattered after rebuilding in the past. I don't know what you mean by engine vibration, but if it shook when you raced it with the clutch in something was obviously not in balance or was off center. I can imagine the flywheel causing both vibration and clutch chatter, but you will appreciate that the pilot bearing being the centering device in the crankshaft that keeps the trans front shaft in line could be the cause of both clutch chatter and engine vibration because the trans shaft is originally very stiff and well supported in the transmission. An off center or worn pilot bearing would cause the engine to vibrate because the trans shaft is a close fit to the pilot bearing. The vibration at speed could well be caused by the clutch plate being slightly off center due to the bad pilot bearing allowing the trans shaft to wobble off center taking the clutch disc with it. Clutching at speed takes the pressure off the disc possibly allowing it to come into better alignment.
I would check the flywheel mounting bolts, clutch mounting threads in the flywheel, the clutch bolts and have the flywheel surfaced. I would replace the clutch plate, pressure plate and the pilot bearing. I would have a trans shop inspect the trans, especially the front shaft and bearing and replace what is needed.
I believe you are planning to replace the u joint. I would go to the extra trouble to do what is needed to replace the drive shaft center bearing. I never did that, but can see where the drive shaft bearing surface and /or bearing might be bad from getting rusty after sitting around for many years before you installed it. The Skip Haney sleeve bearing could fix a bad drive shaft bearing surface.
If the rear mount looks good, I wouldn't be afraid to use it.
I would also look at the transmission front mounting and at the engine/ transmission interface to make the trans is mounting up tightly.
These are the things I would do, but I admit I'm not as experienced in these matters as others here on the barn. I wish you well.

[Old Henry]

Thanks for your caring concern and willingness to share your ideas and suggestions. I will do all that you said.

[Old Henry]

So, whadaya think? Any sign of wear on this U-joint?





(I love it when I don't have to wonder too much about whether a part is worn enough to replace. )

[Ross F-1]

I'd say you got your money's worth out of that! and then some

[PeteVS]

It didn't look like that when you put the rear in, did it? What did you use for lube?

And, if you're taking the rear out, you might also want to pull the trans to look at that pilot bearing.

[Binx]

Amazing you could slip the clutch and get the vibration to sync.

Lonnie

[Old Henry]

Originally Posted by PeteVS

It didn't look like that when you put the rear in, did it? What did you use for lube?

And, if you're taking the rear out, you might also want to pull the trans to look at that pilot bearing.

Didn't look like that when I put the rear in Dec 2012. Used John Deere Corn Head grease but probably not frequently enough. (Didn't add any until last month because I had to lift the transmission up to get a grease gun on the fitting. Will do something different for that fitting to make it accessible for monthly lube.)

Have removed the transmission too to "refresh" it (see related thread) and will also try to figure out something for my clutch chatter, including checking the pilot bearing.

Thanks.

[Old Henry]

Originally Posted by Binx

Amazing you could slip the clutch and get the vibration to sync.

Lonnie

Yeah, I could do that perfectly up until last Sunday. When tried again yesterday before going on a three day road trip starting today I couldn't get control of it so bagged the road trip and tore into the drive line. Glad I did. That U-joint looks pretty bad.

[Mart]

Glad you found the culprit.

Mart.