Shudder, then a rumble at lo revs

[maximillion]

Hi all,

I have something not quite right with the bus, an 81 air-cooled with a CJ engine. When i pull away or reverse i get a shudder and sometimes when i change down, shudder has been around occasionally for a while, but has just got a bit worse and now i can hear/feel a fainter version of this while driving on lo-revs, seams to go away if i dip the clutch... got no noise on corners apart from the other night as i pulled away from a tight bend... i am thinking clutch problem, but before i spend any money, thought i'd get some of your thoughts.

I spent last evening trawling theses forums and got some great advice on what to check, so tonight i checked;

Engine mounts
No real engine movement when wobbled other than the tin wear squeaking and a little but not excessive movement. Mounts look visually ok.
I could only see 4 mounts along the support bar at the rear, 2 each side, is that right other than the gear box mount?

Gearbox mount
Again looks ok but you can see a little movement

Drive shafts and CV joints
When holding the drive shaft there is no up/down or side/side play just in and out, although if i move the actual joint at the gearbox and hold the shaft there is a small click and a small amount of play?
Can you change just the inner joints or is it best to do both?

Oil leaks
Inspected the gearbox and engine joint and there is no oil or leaks, found a bit around the cylinder heads and rod tubes, cleaned and will keep an eye on these.

The gearbox whines a bit, but am hoping to get a few miles out of it, oil looks good and clean, the slave cylinder is a little wet, although this could be from when i recent changed the the master cylinder and blead it? cleaned and will keep an eye on it.

any thoughts?

[Aidan]

I have something not quite right with the bus
When i pull away or reverse i get a shudder and sometimes when i change down, shudder has been around occasionally for a while, but has just got a bit worse and now i can hear/feel a fainter version of this while driving on lo-revs, seams to go away if i dip the clutch... i am thinking clutch problem, but before i spend any money,
The gearbox whines a bit, but am hoping to get a few miles out of it, oil looks good and clean, the slave cylinder is a little wet, although this could be from when i recent changed the the master cylinder and blead it? cleaned and will keep an eye on it.

any thoughts?

clutch slave irrelevant me thinks as clutch is working

rumble but goes away when clutch depressed and vehicle moving so must be input shaft side, so either spigot bearing, clutch or it's the input/mainshaft of box

if oil is clean and plug was clean then either it's had a recent oil change or there really is no wear in there, yet it whines which to me says gearbox, probably pinion and main bearings, box should not be noticeable, noise is box's way of saying somethings worn/wearing wrong

the box has got to come out to check clutch and spigot bearing and probably replace them anyway while you are there, if there's nothing wrong with either of them then it's the box

l

[kevtherev]

yes
your clutch could have oil contamination from a worn and leaking flywheel seal.
This will cause a judder or shudder as you slip the clutch in and out

[maximillion]

Thanks guys, went out for spin tonight and it wasn't too bad, but will take your advice and get the box out to look at the clutch. Do you know where to look for my gearbox number/code or which box for a cj engine?

[fullsunian]

Sounds just like mine....when the spigot bearing went..

[ermie571]

Sounds just like mine....when the spigot bearing went..

after the juddering comes strange behaviour like stalling in neutral....cos although the gear sticks in neurtral, the box isn't! As it started to go, gear changes got a bit stiff....but I didn't recognise this. The day it went, I drove off, went from first to second...it wasn't having any of it....so back into first and tried again....went in fine, carried on. Got to jucntion, and stalled. Just thought I was going mad not taking it out of gear. into nutral, started and drove to lights where I had to stop again. Again stalled. And this time I wasn't getting out of gear. so, called the AA, who were brilliant....checked all linkages, and gear box onion thing....and got neutral, and all gears....so, started engine....and no way...not getting any gear. So engine off, gear selected....and started engine as lights went green....AA followed me the half mile home.....

....it was at this point that I thought the clutch had gone....so replaced it...drove it round the block and crunchhhhhhh...limped back, asked on here, and spend a *delightful* afternoon trying to get the remains of the spigot bearing out!!!

Em
xx

[maximillion]

The spigot bearing sounds the likely culprit... i have a Aircooled CJ enigine, dose anybody know how easy these are to change, flywheel off, puller etc?

[Aidan]

flywheel stays on you will want to take clutch off for access, slide hammer puller is best method, or break them up in situ or hydraulic it out with grease and a spare input shaft/clutch fitting tool
observe that it is fitted beyond flush

[maximillion]

Thanks, sounds straight forward enough... let you know how it goes

[maximillion]

Hey, i know its been a 'long' time since i posted this. Had such a busy summer camping and winter working that i have only just got a chance to strip it down. So thought i'd post my findings...

Just removed the clutch and the friction plate is shot, plenty of meat on it, but one side of it moves side to side and around a bit, and you can see the erratic wear this has caused, so fingers crossed this is the culprit. Spigot looks ok, but i cant see how it would come out with flywheel on? Can this just be re-greased?