Clunk and whine

[Arbman Al]

I have a 1996 130 with 300tdi fitted, which I bought on Saturday last weekend.

I have noticed quite a bad clunk rom the drive train when pulling away, and also a whine/screech over 50 mph in 4th or 5th when accelerating, but stops when taking foot off accelerator and then starts again as soon as the pedal is touched.

Are these two things related?

Rgds...Al.

[nicks90]

could be a diff on the way out with a failing pinion bearing.

my rear diff died like this last year, oil seal failed and let frickley mud/grit in. Bearing started to wear and it started making a horrible whine under load and loads of backlash/slop.

[Andrew Chua]

it could be the transfer box.

i've overhauled my diff for over 300 gbp (1.4k sgd) and it's still whining terribly.

it's going to cost you a entire rebuild of the box if the teeth are also worn out.

What you can try is to find out if it's the front or the back first. remove that prop and drive in diff lock, if you nail it correctly, the whining will be gone, so you have isolated if it's the front or back.

check the diff first, it's easier and cheaper than to drop the t-box.

[Godlykepower]

My first thought would be your diff. Mine died similiar to this not very long ago. The good news is that its fairly cheap (ish) & very easy to fix.

If, unlike me, you have any luck at all, it may only be a propshaft UJ. Get underneath & hold the shaft firmly (oo 'er!) and wriggle the ends of the prop. If there is any excessive play, either from the UJ, or the splines have worn on the shaft of the prop itself, then that could account for your problem. Its also not very expensive to fix. As luck (or lack thereof, in my case) would have it, after replacing my diff, the front prop was on its way out the very next week. A few quid for a replacement UJ, about £100 for a whole new prop.

Dont discount the fact that it could also be your T-box too though, although I dont know how to test for this. Someone with more experience will be along to help soon!

HTH

Martin

[disco_al]

Dont discount the fact that it could also be your T-box too though, although I dont know how to test for this. Someone with more experience will be along to help soon

i was told to put the transfer box into gear, then engage the main box into the gear that was whining and let the clutch out and rev the engine, if it's the transfer box, then there will be no noise, if it's the main gearbox it will still whine. obviously this won't work for the diffs (unless you've got access to a two post ramp.....)

[Arbman Al]

Hi All,

Thanks for your replies and suggestions, it gives me something to do!

The previous owner had the gearbox overhauled and the transfer box was supposedly alright, so will start with the diff and the props.

The noise does seem to be coming from the front.

The front prop will turn about a quarter of a turn if I turn it by hand whilst underneath - should there be any free play like that?

Rgds...Al.

[Andrew Chua]

Turn a quarter!! that's way too much. ok, first suspect would be the diff then.

if you want to find out if it's the t-box, try this.

put t-box into neutral

put g-box into 5

let go the clutch slowly

make sure your park brake is on

crawl under the car and put your ear to the t-box

is it rattling sound?

yes, there is a problem there

no, the problem is not in the t-box

rev the engine

listen if you hear the sound you heard at the g-box by putting your ear there (the engine will be terribly loud from under)

yes, the problem is in the g-box

no, it should be your diff

if the problem is in the g-box, there are a few common things that can go wrong.

the main input shaft or output (to the t-box)

clutch bearing

cluthc plate

my gearbox has not given me problem, so i haven't experiment with anything as yet.

[Godlykepower]

The front prop will turn about a quarter of a turn if I turn it by hand whilst underneath - should there be any free play like that?

Thats far too much play! If you are holding the middle of the shaft of the prop firmly (so that the whole prop cannot move) , then the ends (the bit that slides in and out of the shaf your holding) should only move a fraction of a millimetre when that is wriggled about.

[Arbman Al]

If it is the diff are second hand ones available or do I need to get mine reconditioned?

If reconning is it a diy job or not, I have Hardy Engineering in Leatherhead, Surrey who are supposed to be pretty good with diffs - anyone used them?

Rgds....Al

[nicks90]

second hand diffs can be picked up for £50 no problems. just check they arent worn out first!

[Arbman Al]

second hand diffs can be picked up for £50 no problems. just check they arent worn out first!

Are there tell tale sings if a diff is worn just by visual examination?

[Godlykepower]

If it is the diff are second hand ones available or do I need to get mine reconditioned?

If reconning is it a diy job or not, I have Hardy Engineering in Leatherhead, Surrey who are supposed to be pretty good with diffs - anyone used them?

Rgds....Al

Al, when mine went, I was offered several via the forum for £40-50 second hand. I also enquired about a recon unit, as a company whose name comes up very often on this forum (Ashcroft Transmissions) are local to me.

Money was very tight for me late last year, so I got a second hand unit from my garage, but it cost £80. However, even though it was twice the price of one I was offered, I get an assurance from my garage that it is in great nick.

When I dropped my broken diff, I imagined it would be impossibly complex inside, but I expect if you are quite handy with a spanner, you could recon it yourself. Saying that, if you can get a second hand diff thats not worn, its a very easy job to just swap them out - probably less than an hour.

I was exceptionally nervous about doing this job on my own, and it turns out to be one of the easiest jobs I have done!

Another company that was mentioned to me was Crown Diffs, who are supposedly top notch too.