Improving things worse

[Bazzalucas]

In the course of rebuilding my engine I removed it and noticed that there was no pilot ( input shaft /spigot?) bushing in the flywheel. I dutifully fit one and now my transmission is noisier in all gears than before it had 'support'. Any ideas?

[rayofleamington]

I don't want to insult you, but sometimes it helps to ask 'dumb' questions...

If the oil level is now very low in the gearbox they will be noisier - have you checked the level?
If you refilled the gearbox did you use engine oil?

Running without a spigot bush will accelerate the wear in the primary bearing (the first bearing on the input shaft). Wear on this bearing is also a common cause of noise.

[Bazzalucas]

You will find me very difficult to insult! Yes, oil is 20w50, up to proper level. Strange because this was the only change I can identify. There is particular vibration on the overrun. Shoulda let sleeping dogs lie?

[bmcecosse]

No - you DO need that spigot bush. Have you changed anything else - new gearbox mounting rubbers perhaps?? Is the little wire strap at the rear perhaps too tight? It should be 'just' slack.

[Bazzalucas]

The mounting rubbers were renewed last year, but before the replacement of the spigot bush, and the cable has a bit of slack to it. (That was my first thought, too). I need to have a prolonged look-see under the car to see if there might be a secondary vibration (exhaust?) problem; i.e., perhaps in refitting the engine I tweaked the exhaust a bit somehow? I'm grasping at straws. I suspect Ray is probably on to something with his idea about the input shaft bearing. Sigh.

[bmcecosse]

It won't have been helped by running without the spigot - but once you are in top gear - that bearing has little to do since the drive is straight through the gearbox. Is the vibration any less in top? Have you refitted the prop shaft exactly as you removed it? Any chance it is not back in the same holes as before on the final drive input flange?

[Bazzalucas]

It is noticeably smoothest in top, but upon letting off the gas I get a pretty buzzy vibration. I did experiment with the prop shaft, rotating it 180 degrees, (no change).

[izzi]

With the spigot bush missing,was there excess noise from the gear box prior to your discovery.
I was just thinking if part of the old spigot bush is still partly stuck in the flywheel including the new one, hence the new noise.
Roy

[Bazzalucas]

No, I am certain that there was no old bush...nor grease nor anything. The noise was not there prior to fitting the new one.

[izzi]

Have you any idea why the spigot bush was missing in the first place.
Best of luck with this one.
Don,t suppose you can try another gearbox to eliminate the actual gearbox bearings etc;
Roy.

[Bazzalucas]

My best bet is to find another Midget 'box. Here in the States Mogs are a little thin on the ground. Oh, and no, I have no idea why the bush was missing. Wasn't on my watch!

[izzi]

If you have to remove the gear box, a thorough inspection may reveal necessary bearing replacement.
As you say it will be difficult getting a box in Michigan, USA.

What ever you do I hope the problem will soon be solved.

Roy,