Very hot front wheel bearings

[john davis]

Just had my 1990 T25 garage serviced....getting too decrepit to do it myself! They changed the front discs, put in new pads and bearings. The problem is that the bearings (on both sides) are getting way too hot...too hot to touch in fact. I discovered this after about 10 miles when I stopped and could see melted grease seeping out from beneath the hubcaps. Straight back to the garage..the mechanic in charge reset the bearings and pronounced it ok. Drove about 25 miles, parked up in a car park and repeat performance when I got out. Back to garage again....all stripped down again, mechanic took it for a 5 mile test drive and bearings far too hot again! He's checked brakes aren't binding, the new discs aren't warped and he's declared himself defeated.....and I've already parted with £450! It was fine before I took it in. The trouble is, we're supposed to be off on hols. tomorrow with a total drive exceeding 1,000 miles; the idea was to make sure the van was fit for the long drive. Has anyone any ideas what the problem might be? It certainly wasn't getting the bearings hot before the servicing took place. I'm not sure whether I dare risk going away.

John

[SplendiferousII]

I take it that there are no noises coming from the wheels, scrubbing ticking or knocking?

He jacked the front end up and spun the wheels to check they are free? No binding or dragging?

He wobbled the wheels to check there was the tinniest amount of play?

Is the grease just the excess being pushed out or is it turning to oil and p i$ $ ing out

The bearing shouldn’t really even get warm as they are so over rated for the duty. They will get warm if they are over packed with grease, but that will sort itself out.

You sure its not just heat from the disks?

Unless its making a noise or you can feel it through the steering, drive on and enjoy your hols. It’s only 1000 miles after all.

[g60steve]

GSF wheel bearings?

[R0B]

if they are the gsf chinese ones.that will be melted chocolate..

could see melted grease seeping out from beneath the hubcaps

[toomanytoys]

How has he set the bearings? there needs to be a small amount of play when cold.. You must be able to move the washer behind the nut.. other than that, the pads are dragging on the discs.. (rear shoes adjusted up to tight?)

[john davis]

Ok....the holiday is on hold till this is sorted out Just done around 10 miles to get fuel for hols. and the heat coming from the wheel area is intense. I've been back to the garage, the boss man works late! Neither of us is sure whether it is bearing or disc related but, having stuck my finger through a wheel aperture I can confirm that the discs were very very hot and I now have a blister to show for it. The bearings were not over-packed but it is melted grease that's coming out.
So, what's the root cause???? When jacked up - both wheels spin freely with no binding at all, the brakes come on and release normally....no delay in coming off which might have suggested a collapsed hose(s). He's checked that the discs sent were the correct ones....at least according to the box. Apparently there are two types listed for my late van, one (Bosch) is 1mm thicker than the cheaper variety; he fitted the Bosch type. Would that 1mm make all the difference? He thinks not as there's no binding whatsoever. He says that the bearings were correctly set....I will check myself when everything's cooled down to make sure there is the specified slight movement of the thrust washer.
Oh well...what will be will be; at least he says that he's making no charge for this extra work.
John

[SYNCROSPARESUK]

I doubt it's your bearings, much more likely to be brake related, we had a very similar situation with a bay recently, new pads and disc some other pipework, which meant system had to be bled completly.....anyway one of the seals in the master cyl turned and caused residual pressure in the front system not allowing the front brakes to release properly, the wheels would still turn relativley freely though they felt a little to tight to me, released the bleed nipple on the front caliper and fluid was released and hence pressure....wheels span freely....new master cyl, sorted it out.

[dugcati]

Added to what Syncrospares has said it's also worth checking the pistons are returning back into the callipers -better still take them off the mounts and use a g clamp to push them fully home them pump them out again and repeat a time or two.

If the callipers are not returning after brake application then the pads dragging on the discs causes heat build up and expansion then more heat then more expansion.... you get the picture

[billy739]

drive the van along a dual carrigeway or motorway for a couple of miles,stop and check the heat!

that should figure if its the breaks or not.

the hubs do run warm , not sure why , mine do , initially when i found this out i was a little concerend, but i have since checked other vans and they all seem to be the same!
i kept checking mine 3500 miles through europe ,always the same , plus before and now were home , no problems /faults with the bearings and ive probably done 10000 miles so far!

personally also i would make sure he has used the correct grease with a high melting point ideally special wheel bearing grease, if its normal stuf it will turn to oil when heated!

get him to show you the container he used!

[Fritz]

Question : did you have the rear brakes checked /cleaned/ adjusted as well as the work done to the fronts ?

My guess is : rear brakes have been adjusted up too much which can lead to the brake fluid boiling,,,,,this can lead to the front brakes dragging : hence the very hot front brakes.


I will now sit and wait for members to rubbish my theory/guess,,,,,,, ( you know who you are and it is starting to pi$$ me right off )


Regards


Fritz,,,,,,,,,,

[toomanytoys]

Question : did you have the rear brakes checked /cleaned/ adjusted as well as the work done to the fronts ?

My guess is : rear brakes have been adjusted up too much which can lead to the brake fluid boiling,,,,,this can lead to the front brakes dragging : hence the very hot front brakes.


I will now sit and wait for members to rubbish my theory/guess,,,,,,, ( you know who you are and it is starting to pi$$ me right off )


Regards


Fritz,,,,,,,,,,

As I prev suggested Fritz.. but generally they wont "boil" the fluid.. just creates some residual pressure making the fronts drag..

[camper]

Just a thought here could it be due to internal collapsed front brake hoses.I had a problem with front brakes running very hot on a Aircooled T25 the caliper pistons wouldnt return properly .The hoses where replaced with new and brakes and front discs tempreture normal.

[dugcati]

Just a thought here could it be due to internal collapsed front brake hoses.I had a problem with front brakes running very hot on a Aircooled T25 the caliper pistons wouldnt return properly .The hoses where replaced with new and brakes and front discs tempreture normal.

dejavue....

.....Added to what Syncrospares has said it's also worth checking the pistons are returning back into the callipers -better still take them off the mounts and use a g clamp to push them fully home them pump them out again and repeat a time or two.

great minds think alike hehehe

[john davis]

Thanks guys for all your suggestions....but no luck so far. Just come off the phone from the garage and the fitter says that he's running out of options. He's backed off the rear brakes and likewise with the front wheel bearings but still getting hot discs and hubs after just a couple of miles. He seems certain that the flexible pipes are ok as the brakes come on and let go straight away....he checked it with the wheels off the ground. He's checked the pistons go right back into the calipers as well. Given that he's looked at the rear brakes and bearings again, I suspect it might be master cylinder issues as elswhere suggested....that's tomorrows's job! If not that I'm going to push him to replace the discs and bearings that he provided. Holiday well and truly up the chute now!
Will keep you posted....John

[john davis]

At last problem resolved....the discs that the supplier provided the garage with were too thick - 16mm in stead of 15mm. When everything was cool there was miniscule brake drag, once it had got warm obviously the drag got more and it self perpetuated. I just wish the fitter had compared the discs he removed with the ones sent. However, it took 10 days and my intervention suggesting that he try spinning the wheels when hot that finally proved the point to him. He's now wondering about who's going to bear the cost of the wrong discs....I''ve made it clear that it ain't me, I've already lost a fortnight's holiday!!!
John