HELP with mechanical trouble en route to Africa.

[davidnavin]

G’day.
I’m currently driving between London and Cape Town. My 1994, manual T diesel VX is making a horrible noise and I cannot diagnose it. Best way t describe it is a medium pitched groan. Sounds like the noise made when a big boat is up against a dock and the hull slides up/down a pile or buoy. Characteristics as follows:
• Comes from up front possibly more towards passenger side
• Causes some vibration in the floor.
• Mostly happens when changing gear but sometimes when not changing gear, mostly on downhills, sometime flats, never on uphills.
• Often at low revs e.g. when on freeway in 5th and gradually slowing down for an exit i.e. slacking off the accelerator.
• Doesn’t seem to happen when driving it hard
• Very unpredictable. Don’t hear anything for a day or two and then it will start up and happen on and off for hours.
• Normally only for a few seconds or less.
• If it is happening then it will happen a number of times. Generally until the car stops for a while.
• Don’t lose any torque/power when it happens

Once on a long downhill it started groaning and would not shut up for 20 seconds or more, even when rolling in neutral. Finally stopped when we turned steering wheel and pulled into side street. We sat and swore at it for half and hour while we had lunch then got in, drove off and did not hear the sound for days.

Have had mechanic look over it but of course when he was in car it was silent. He put it up on lift and together we gave it a fairly minute visual inspection. Nothing out of place. Rocked all 4 wheels and bearings sound fine. Mechanic was a cruiser fanatic and seemed to know his stuff.

The problem with it is that because it is unpredictable/sporadic we cannot time the noise with a visit to mechanic. Whenever it is happening we look for mechanics but don’t find any. Unless we can get a mechanic to drive the thing when the noise is happening our only option would be to get a mechanic to start pulling open clutch, diff etc which I am not keen to do. Any thoughts would be much appreciated. I’m particularly keen to ensure that we are not wrecking the vehicle by driving it.
Thanks

 

[Gav Peter]

Have you tried dropping the props to check they are in good order David?

If you do them one at a time & then lock the centre diff you can still get drive... Its awful trying to isolate these things when they are so sporadic...

Good luck

 

[sae70]

The only thing that springs to my mind that has not been mentioned is the engine mounts

 

[Olazz]

David,

I had what sounds like the exact issue on my 80. See the link.

Was eventually traced to a dry CV. They has just been done a few months earlier.
Hope you sort it.

viewtopic.php?f=15&t=9569

 

[Andrew Prince]

Another thing worth checking are the bushes, particularly caster correction bushes if you've had these fitted. If you have CC bushes fitted, check the radius arm (where the CC bushes live) mounting on the front axle as this can crack.

Otherwise bushes in any of the control arms or anti-roll bars could make horrible groaning. If it is a dry/failing bush, it's probably not critical but if you can remove the pin/bolt/bar going through the bush and grease with red rubber grease or some other suitable grease, it might make the bush last until you can replace it and stop the groaning.

CVs and UJs are MUCH more critical so check those first. A cracking radius arm mounting on the axle is also pretty serious. Bushes perishing and groaning are not as vital short-term.
Also check the wheelbearings when accessing the CVs.

Cheers,

 

[Jon Wildsmith]

Check the passenger side engine mount hasn't seperated by lifting that side of the engine, or examine the sump/block near the engine mount for witness marks of contact. Reversing up a steep hill would make the noise if it's this.

 

[Cptsideways]

David,

I had what sounds like the exact issue on my 80. See the link.

Was eventually traced to a dry CV. They has just been done a few months earlier.
Hope you sort it.

viewtopic.php?f=15&t=9569

THIS!!!

I had exactly the same, its the wheel bearing having play & causing play in the CV the abs ring/hub then runs on the sensor & causes a buzzing vibration as & when you described.

 

[Offroads4x4]

I would look at the drive lines and u-joints for play. Also have you greased the drive line lately?
Just some ideas to check out.

 

[davidnavin]

David,

I had what sounds like the exact issue on my 80. See the link.

Was eventually traced to a dry CV. They has just been done a few months earlier.
Hope you sort it.

viewtopic.php?f=15&t=9569

THIS!!!

I had exactly the same, its the wheel bearing having play & causing play in the CV the abs ring/hub then runs on the sensor & causes a buzzing vibration as & when you described.

Havent had net access or driven the vehicle in 10 days. Drove from Cairo south today and the noise was still there (albeit very occasionally). Will follow up on all suggestions but it could sounds like the above could be it. Any idea how I fix it?

 

[Cptsideways]

First: Pull the hub dustcap & check you have a C Clip on the driveshaft flange - it might have popped off! This might be the problem!! Its likely the C Clip has broken or worn through its groove. If so replace C Clip or you can weld a washer on the driveshaft to locate it in place - first measure opposite side to get the CV/Shaft in the right place to run true inside the hub. Its a temporary bodge but it will work fine if you can keep the dust out of the CV flange, (use some silicone or similar) Obviously finding a CV Joint/C Clip etc will be on your shopping list if this is the case.

Wheel Bearing: Jack up a corner & check for bearing play first, see if its the wheel bearing by checking the brake disc in the claiper for movement. If the whole wheel/hub assembly moves then its the hub pivot bearings (which have shims to adjust them)

Wheel bearing adjustment is easy: You can leave the wheel on Dust cover off, C clip off the driveshaft, 6 bolt flange off (it will need a light tap to release) dont lose the tapered spacers leave the nuts on until they are free. Now you should see the hub nut under the grease, release tab washer, you'll need a 54mm socket (or a hammer & screwdriver if desperate) to remove the first nut at least.

Now there is a set procedure for adjusting them, this is a simpler version that will work at the roadside. Tighten inner nut until there is just no play, (its not very tight) rotate wheel a few times, check again. About 1/4-1/3 of a turn past no play in the bearing is about right. Don't overtighten them its easy to do! Refit tab washer, make sure inner nut is located by at least 2 tabs, refit outer nut & tighten up a fair bit, bend tabs over. Check for tightness/play again. Refit flange & C clip, theres a 6mm thread you screw a bolt in to hold the driveshaft at the right point when fitting C Clip, refit dustcap etc.

If the bearings are too tight they overheat quickly, hubs should not be hot (warm'ish is ok) even at higher speeds, check by coasting to a stop not braking if poss.


Hub Bearings: I've never adjusted any only ever fitted new ones, but its a hub rebuild job, which is doable at the roadside TBH - its just a very messy one.