vibration

[4tford]

Pulled my motor and trans from my 53 Mainline Found the throw out bearing housing is coming apart and the bearing, which feels good moves from side to side on the housing .030". Would that cause a vibration?

[JSeery]

I wouldn't think the holder would it stays fixed and does not rotate. The bearing should center on the transmission front retainer. Check the bearing fix on the retainer. I would be looking at the pilot bearing or bushing.

Did it just start or has it always had a vibration?

[4tford]

vibration has been there since I bought the car, everything other than motor, trans and clutch has been checked and or replaced. Vibrates sitting or running. When running playing with clutch will reduce but not eliminate. Also found this retainer clip missing. Pilot bearing is good.

[JSeery]

If it's in the bearing/retainer assembly it would about have to be the bearing itself, that's the only rotating part. Have you checked the bearing to front retainer fit?

Was the flywheel, pressure plate and clutch balanced?

[Fourdy]

Bill,
OK, I know this doesn't help but if I could move .030 side to side I would vibrate. LOL

Fourdy

[40cpe]

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The throw out bearing shouldn't touch the clutch or move with the pedal released, therefore no vibration.

[4tford]

Pistons vary .8 ounces in weight. Entire rotating assembly will be professionaly balanced next week.

[JSeery]

Originally Posted by 4tford

Pistons vary .8 ounces in weight. Entire rotating assembly will be professionaly balanced next week.

How did you determine that?

[4tford]

I weighed them on a postal scale.

[GOSFAST]

Originally Posted by 4tford

I weighed them on a postal scale.

Hi "4t", list all your components if possible, helps some in solving issues??

Thanks, Gary in N.Y.

P.S. If I'm reading the piston info I see a 22/23 gram difference between them?? There's 28.5 grams/oz, multiply that number by ".8" and it works out to 22.8/per piston to be exact.

[JSeery]

Originally Posted by 4tford

Pistons vary .8 ounces in weight. Entire rotating assembly will be professionaly balanced next week.

That might be a factor!

[4tford]

I spent the day with my daughter going through this motor. It was built on the cheap for a guy who wanted it that way. Rods an pistons matched somewhat . Heavy rod with light piston etc. I don't do this anymore even though it worked in the past. In this case I am guessing the crank is way out of balance as well as discrepancy in piston and rod weight. Valve train is good so will keep that. I have a set of reconditioned rods, a fresh ground 020/020 crank as well as new Egge pistons and rings. Will take block in for a rebore. New rotating assembly will be professionaly balanced.

[Ronnie]

Don't think you are getting any accuracy from a postage scale. Also no bob weight calculation.
Those numbers are of no value.

R

[4tford]

Why no accuracy on a postal scale? No bob weights as nothing was ever balanced.

[Ronnie]

Does the scale read in one gram increments? If nothing was balanced why bother.

R

[GOSFAST]

Originally Posted by 4tford

I spent the day with my daughter going through this motor. It was built on the cheap for a guy who wanted it that way. Rods an pistons matched somewhat . Heavy rod with light piston etc. I don't do this anymore even though it worked in the past. In this case I am guessing the crank is way out of balance as well as discrepancy in piston and rod weight. Valve train is good so will keep that. I have a set of reconditioned rods, a fresh ground 020/020 crank as well as new Egge pistons and rings. Will take block in for a rebore. New rotating assembly will be professionaly balanced.

Those number's on a factory unit are right where they belong based on the info I have on hand? A single factory rod, piston, pin, rings, and clips would be in the area of 1084 total.

Using these number's above I would say the bobweight for this setup should in the area of 1600 grms, give or take a few.

I suspect that any vibration will most likely NOT be caused by the variations in the posted numbers?? It doesn't add up.

(Important note on brg clearance) If the shaft is NOT already at 20/20 I would take this time to "build-in" the EXACT desired clearance, now is the time!! It gives you the opportunity on BOTH the mains AND the rods to get .001", .0015", .002", .0025", whatever you choose. This is how it's done here, we "build-in" the clearance we want! You CANNOT do this if you cut the shaft first and then check the clearance, at that point you cannot correct it. This method eliminates any "tolerance-stacking" AND potential oil-pressure issues down the road! See the photo below.

Thanks, Gary in N.Y.

P.S. The issue is still you have no way of knowing how this bobweight total would make the shaft react, it would have to be run up and read.

[4tford]

Yes to one gram. I am trying to find out what is causing the constant vibration.

[Ronnie]

Originally Posted by 4tford

Yes to one gram. I am trying to find out what is causing the constant vibration.

Why i asked as your original post stated difference was in oz. not grams.
Engine balance has used grams for a long time.

R

[Ross F-1]

Check the runout on the flywheel as mounted to the crank.