GolfGTIforum.co.uk
Model specific boards => Golf mk3 => Topic started by: jezza16v on 11 February 2010, 21:18
-
Hi all. Just replaced the aux belt and tensioner pulley on '96 90 bhp tdi, no prob. Started the car up and let in run to charge up the battery. It ran nicely for about 2-3mins and then there was a horrible rattley tapping noise. We immediately stopped the engine to make sure all we had done was fine, was all still there and good. went to restart the engine and .......zip! It turns over well and we can smell diesel but it will not start, when the starter is turned off there is a buzzy clicking noise from near the fuel filter, but maybe that's normal? Help what has happened............Arrggghhhhhhhhhhhhhh! :undecided: :sad: :sad: :sad: :sad:
-
I wonder if the timing belt tensioner went? Maybe it jumped a couple of teeth - it drives the injection pump on that engine does it not?
Hope its not serious as that tho mate, its a downer when they pack up mysteriously.
maybe the lift pump disintegrated, now wont prime the injection pump? Where was the rattling coming from, and was it light or deep?
-
Thanks, that was quick! It was definately a light rattle from the engine bay, but the bonnet was down so can't be more location specific. We took the cambelt cover off straight after to make sure it wasn't snapped, it wasn't but the cambelt and pulleys were completely smegged with oil, its not an old belt because the cylinder head was replaced a couple of years (20k) back (according to documents) so it was replaced then but the camcover gasket has been leaking oil for ages at the pulley end, we only fixed that a couple of weeks back but we guess the gasket was 'pinched' when the head was done (we've only had the car for 4 weeks btw). There is no tapping or rattling when we turn the engine over on the starter, it sounds normal, and it can be turned over fine on the crankshaft pulley bolt.
We thought cambelt 'slip' but is there an easy way to tell. The engine did not stop of its own accord, we had to turn it off with the ignition......Is that any more helpful? :sad: :undecided: :sick:
-
its possible it jumped one or two teeth at most if it was still running, any more and it would have definately stalled, the only way to tell is either line up the cam pulleys and the crank pulleys with the marks on the engine casing, or do a compression test in one of the injector holes, but lining it up is easier without the proper gauge to read comp. If the belt jumps, the valve timing goes out slightly and that would make it hard to start.
Also if you unscrew one injector and crank it, there should be a nice burst of diesel every rotation, proving the injection pump is getting driven, tho if the belts not broke then it should be, but will show if fuel is getting to it from the tank too. Maybe the injection pump has failed inside, its very possible and may just be bad timing (no pun intended lol) and not related to the aux belt repair. Nothing else was slackened on the engine when the aux belt tensioner was done?
-
No, nothing else was touched on the engine while doing the aux belt. Just in case we haven't yet jumped the belt enough for the pistons to to clout the valves, we don't want to risk turning it over on the starter any more until we've checked the pulley alignments. But we wonder what the 'tapping' was, would that be the valves hitting the pistons or what? I've never heard that happen before but I would have guessed it would be a much louder scary sort of noise than the tappety tappety noise we had. Thought the engine would have stopped if the pistons hit the valves, it was just left ticking over to charge the battery. We watched the engine turning over on the starter with the cambelt cover off, all the pulleys are turning fine but the belt does seem a bit 'sloppy'. I guess I could have a go at putting some more tension into the belt with the tensioner just to make sure it does not slip any more while were fiddling with it.
Could it be anything else dumb and simple we could be missing? :undecided:
-
I doubt it, but the injector pump isn't by any chance run off the Aux belt is it? Or anything to do with it?
-
no its off the timing belt.
I just wondered if the tb tensioner had been slackened by mistake, etc.
The aux belt is likely nothing to do wi the problem, id look elsewhere mate. If the tb jumped 2 teeth max, theres no piston contact. The valve timing would be out, maybe causing a kind of diesel death-rattle with the late timing causing a cooler charge so the diesel wouldnt burn completely?
Did it smoke out the tailpipe when the rattle started? Diesel smoke I mean.
-
Yeah that's what I'm thinking.
I have seen cars where they run of a double layered pulley off the aux belt, wasn't sure if these were similar.
It sounds to me like diesel slap, timing out. Most of the time when injector pump is out they are hard to start, rattle, pour out smoke and don't idle.
-
Yeah that's what I'm thinking.
I have seen cars where they run of a double layered pulley off the aux belt, wasn't sure if these were similar.
It sounds to me like diesel slap, timing out. Most of the time when injector pump is out they are hard to start, rattle, pour out smoke and don't idle.
+1 check the timing.
-
We think it did start smoking, was dark, so hard to be sure, we thought at first it was a 'puff' from under the bonnet but think wind may have blown it under the car and out from the front (the wind was blowing that way at the time), we stopped it pretty quickly so not much smoke really. As said we were getting that unburnt diesel smell when cranking it over when it wouldn't start. Looking at the oily state of the cambelt and all the pulleys we're going for the belt slipping diagnosis, but which pulley do they normally slip on? I guess there's not much load on the injector pump pulley so unlikely to slip on that, most likely on the small crankshaft pulley which is doing the work or maybe the camshaft, that has a lot of resistance due to the valves.
Thanks for your comments so far, any other wisdom is more than welcome.
We'll have a closer look at the weekend and keep you posted on what we find. :smiley:
-
If it is dumping fuel into the cylinders then the timing is out.
-
It would seem that way.
I know you all like a pic or two so here is the beast and that smeggy cambelt.
How do the tensioners work on these? When you push on the belt the tensioner pulley seems to be spring loaded so not sure how you can set the tension. Not at all like mk2 that I'm used to. Haynes manual any good for these? :undecided:
(http://i60.photobucket.com/albums/h30/jezza16v/IMG_5167.jpg)
(http://i60.photobucket.com/albums/h30/jezza16v/IMG_5161.jpg)
Apologies for those wheels, they came with the car and with brand new tyres.
-
hey love that colour! Looks turqoisy like my 200SX.
And those wheels look ok on the 5 door.
Looks like maybe the cam front seal or idler seals are leaking onto the belt. It would slip on the crank or cam pulley, line it up again and change the belt cos it'll be better than reusing the old one...
Hope thats it mate. Pretty certain there.
-
Thanks, plan to strip down and do the cambelt & tensioner, we think/hope oil is from pi**ing previous oil leak in camcover gasket at belt end. We'll risk £50 on that and if the engine is found to be damaged we'll break the car.
Any idea how that tensioner works?
-
thats a good point. the cam cover leaks like a b!tch if the oem gasket rucks up.
I think from memory that the tensioner is wedged back away from the belt using a bar, then a pin inserted into a hole to lock it in place while you change the tb.
Is there a hole in the face of the tensioner?
-
Sorry to hear of your probs with timing belt etc, hope you get it sorted, thats funny you having those wheels on, iv a tdi on a p reg and have the same wheels which were already on the car (http://i148.photobucket.com/albums/s27/Paul5_photos/76dd_3.jpg)
-
FlySpeck, this is the tensioner? I'm worried that the clattery rattle when it happened was the pistons hitting the valves?
I've read that its worse when the belt slips rather than breaks as it means that the valves get clouted in every cylinder rather than just one or two?
(http://i60.photobucket.com/albums/h30/jezza16v/IMG_5169.jpg)
Pablo 64, Those wheels look better on yours, maybe the different arches, have you lowered/stiffened it it at all? Ours is really 'rolly polly' on the handling side. The main prob is the drums on the rear, they look really naff compared to discs with these wheels.
-
Hi Jezza, iv not got those arches on now, didnt like em and no its not been lowered, like your its "rolly polly" i want to lower and stiffen it up abit but that many kits out there dont know what to go for, presume your wheels are 17in as mine are
-
Yes, 17 with 40 profile tyres.
-
Hi Jezza, did you sort your timing belt out
-
Not yet, have to get those mk2 out of the garage, so we can get this one in, red one is work in progress, should be on to it this weekend hopefully. Can't be bothered doing tricky stuff outside, just too cold & wet atm.
-
OK, took the camshaft cover off and the flywheel plug out to check the timing.
The camshaft was only 1 tooth ahead of the crank pulley and the injector pump six teeth ahead of the cam pulley, so lucky us! Seems like no damage to the valves........so why was this......well, when the aux belt tensioner disintegrated one rib of the aux belt was stripped off and got wrapped around the back of the torsion damper and then dragged into the crankshaft cambelt pulley, spun around and chewed up disintegrated and sent around the other pulleys so no wonder a few teeth were skipped.
This is what I found behind the torsion damper
(http://i60.photobucket.com/albums/h30/jezza16v/IMG_5172.jpg)
This shows the smeg behind the torsion damper, the plastic cover looks thick with grease, but its not, the plastic is scored and melted, I guess by the shredded aux belt!
(http://i60.photobucket.com/albums/h30/jezza16v/IMG_5171.jpg)
This shows shredded bits squished into the cambelt teeth.
(http://i60.photobucket.com/albums/h30/jezza16v/IMG_5173.jpg)
This shows a scuffed belt tooth where it has slipped.
(http://i60.photobucket.com/albums/h30/jezza16v/IMG_5174.jpg)
This shows a piece of aux belt stuck in the cambelt idler pulley.
(http://i60.photobucket.com/albums/h30/jezza16v/IMG_5175.jpg)
This is that piece pulled out, you can see the imprint of the cambelt teeth in it!
(http://i60.photobucket.com/albums/h30/jezza16v/IMG_5176-1.jpg)
We thought that the previous owner had put a five rib aux belt on, the new one we put on was six, clearly the old one was a six rib, but 1 and a half ribs had been shredded off. So It looks like we got off lightly, a good clean up, new cambelt and tensioner & re-time and away we go. Will be next weekend now so will let you know how it goes then.
-
Nasty, fingers crossed
-
Just put a new cambelt on this morning and it runs a treat, no valve damage at all. Phew! :grin: :grin: :grin:
All that grief and effort just because the aux belt tensioner pulley broke up.........for a few quid, if you've got an aux belt and tensioner pulley that's been on a while, suggest you get them changed. On this one I reckon the tensioner pulley was original (125k), not sure about the belt. The main reason it failed was because water got into the bearings and rusted them out, there were no bearings left in it, just the inner race and the outer plastic wheel which fell off and let the belt go.
-
nice one mate, sweet ;)
-
Great result. :cool:
Every service I take the pulley off and grease it up, then grease any other pulleys as well because of this very reason!
-
glad you got it sorted, and thankfully no serious damage, nice one mate :smiley: