granprixweiss928

I have my TT out, and disconnected from the trans. Main shaft and bearings still in place. 61K miles- 5 spd 1981.

I can easily spin the axle by hand. it sounds a little dry...Im planning on bearing replacement- its why its out.

But when I spin it-fast- I can see the shaft spin slightly out of round. I put my micrometer on it- on the axle- at the Trans end- on the part where there is no splines- the recess where the bolt from the clamp goes.

I found the low spot and zero-ed it, then spun it slowly by hand, and got about .30mm deflection max.

Is this a concern? Would it be corrected with new bearings?

Mark

Mrmerlin

your shaft is bent the WSM may have a spec for that likely someone removed/ installed the transaxle and bent the shaft

dr bob

Check the shaft while it's out of the bearings and on the floor. The ends get bent when they are dangled (not supported well) by one end on removal.

GlenL

Did you notice any vibration or humming before removal? Any chance you bent it afterwards? Are the bearings at the right spots in the TT or have they walked away from that end?

I guess I'm wondering if it'd work fine anyways.

granprixweiss928

bearings are in correct place, the did not migrate. I had vibration around 70-80 mph

I took the TT and trans out together- then separated very carefully on the floor with everything supported. From what I can tell, its not be taken out before.

Mark

Speedtoys

Ya..I was there. It could not have been taken apart any more "evenly laid out" than he did it.

Constantine

Hi Mark,


New bearings will not correct a bent shaft vibration.

Also a bent shaft vibration increases with RPMs and usually does not manifest at a small range of operation or speed. If it was speed related there are a lot of other rotating assemblies that could have caused the vibrations.


Best to check for vibrations with the car stationery, clutch in neutral and raise the engine RPMs slowly to see if it is drive train induced. Obviously not something you can do at the moment.

Good luck with the diagnosis.


Constantine

granprixweiss928

I never noticed any vibrations at idle.

the highway vibrations could of been many other things, I agree.

My engine is apart- slightly bent rods found, bad bearings. other weird things all being corrected.

my tires are 10 years old...etc etc.

I am surprised to find this.

Mark

the flyin' scotsman

I'd take the shaft out and carfully measure deflection at various points throughout its length.

Set the shaft on V blocks and use a magnetic based dial indicator. Good luck.

GregBBRD

^^^^^This.^^^^^

With all the care you took getting it out, make sure something is not wonky with the bearings, before going any further.

Bill Ball

WSM spec is 0.8mm runout.

granprixweiss928

thanks Bill. So its within spec then since I measured .3 mm with my dial indicator.