Les Henson Posted April 18, 2006 Share Posted April 18, 2006 I fitted a new timing belt and tensioner to a 2.5TD 90 back in Feb of this year. Less than 2000 miles and it snapped at 60mph - cracking a rocker and bending rods. Everything looks ok still, just the snapped belt. I have pretty-much always used Dayco belts, and have never had a problem with them. Anyone else ever had problems? Can the broken belt be inspected for bad construction? A short while ago the engine was stalled through water ingress through the air filter housing and into the cylinders. Although there was no damage to the engine fortunately, would this cause excessive strain on the belt, causing it to be so weak as to fail at a later date? Les. Link to comment Share on other sites More sharing options...
GBMUD Posted April 18, 2006 Share Posted April 18, 2006 IFAIK Dayco are OE and therefor should be good quality. Did you inspect all the tensioners, idlers and pulleys for damage, bearing play etc too? I am guessing you did as you know what you are doing. As you know, JST and I have both suffered belt failiours recently too - a bad batch? I can not see that water ingress into the cylinders would have made a lot of difference to the belt. I suppose it could have made valve opening a little more difficult just due to water pressure - and I am sure that Dayco would argue that too - or poor fitting, or existing damage to the pulleys etc.... The question more relevant is; did water get into the timing chest at the time of the other incident? It could have seeped in via the front crank seal and then gone un-noticed during the repairs to the rest of the engine before seeping out/vapourising in use. Water getting between the belt and the pulleys could stretch it as the belt "aquaplanes" on the water therefor stretching it. IIRC the Kevlar in the belt can be damaged by the water too, causing damage. Perhaps if the wading plug were left out and the water just got in before running out again a few minutes later? All the best for mending it - take some pics for the archive. Chris Link to comment Share on other sites More sharing options...
Turbocharger Posted April 18, 2006 Share Posted April 18, 2006 I'd suspect the installation, I'm afraid. Not to cast aspersions on your workmanship but it sounds like something was awry there, perhaps the belt bedding in and stretching too much? I hope it's not a bad batch, I replaced mine about 6 months ago On a lighter note, I saw a timing belt for sale at Sodbury with half the backing worn away (as misaligned 300Tdi's do)... Link to comment Share on other sites More sharing options...
Les Henson Posted April 18, 2006 Author Share Posted April 18, 2006 Thanks Chris. Tensioner was new as well. I fitted a wading plug myself and new outer cover crank seal. All belt sprockets were fine, and it seems that the belt just failed for whatever reason. Local garage where it broke down did the repair. Les. Link to comment Share on other sites More sharing options...
Les Henson Posted April 18, 2006 Author Share Posted April 18, 2006 I'd suspect the installation, I'm afraid. Not to cast aspersions on your workmanship Really? reads that way to me. I install belts to manufacturers spec using correct method/tools. Hate to say it John, but I kinda hope your belt snaps now, at least it wouldn't be my fault. Les. Link to comment Share on other sites More sharing options...
Turbocharger Posted April 18, 2006 Share Posted April 18, 2006 Really? reads that way to me. I install belts to manufacturers spec using correct method/tools.Hate to say it John, but I kinda hope your belt snaps now, at least it wouldn't be my fault. Easy there, fella. I'm trying to broach a sensitive subject here. If a garage installed my belt and it snapped after 2000 miles, I'd blame them. If I installed it and the same happened, I'd look at my installation method before blaming the belt, especially if everything else looked ok in there. If you're happy with your method then you've more confidence than I do, that's all I guess. Best of luck getting it repaired and back together, anyway. Link to comment Share on other sites More sharing options...
Les Henson Posted April 18, 2006 Author Share Posted April 18, 2006 I don't think I'd blame anyone at this stage. Other mechanical problems could cause the belt to prematurely fail as well as a manufacturing problem. Further investigation is the best way to go before accusations of poor workmanship starting flying about. Human nature being what it is (and you are nobodys fool, so I think you know), do you think that someone reading your reply would still be prepared to pay me to repair their vehicle? Every owner of a L/R that I repair gets pointed towards this site, and a few already members have had their vehicle repaired by me. Considering the damage I could do to myself income and reputation-wise, I don't cut corners or bodge (within what's acceptable). I feel your reply accuses me of doing the job badly, that's how it reads - and I respond defensively. Les. Link to comment Share on other sites More sharing options...
Turbocharger Posted April 18, 2006 Share Posted April 18, 2006 It wasn't meant as an accusation - you're quite right that the belt could have failed from manufacturing defects (Six sigma allows, what, 3.5 ppm failure?) or the manner in which it was installed. Since you followed the book I can't see you're to blame personally; I've seen the way that factory repair methods are produced and it's .. ahem .. imprecise. I'll still say that the quality of your workmanship is borne out in every job you do - you don't need the forum as an advert, just any piece of past work that I've seen. There are very few people I'll give my car and money to, but you'd be one. I think my timing belt's safe from failure for a while yet though - the car's parked up while I'm abroad! Link to comment Share on other sites More sharing options...
simonr Posted April 18, 2006 Share Posted April 18, 2006 Assuming the original installation was OK (You nasty man - Turbocharger), I would have to suspect water ingress. The Kevlar fibres in the belt are denatured by water which tends to weaken it some - and they stay weakened. Even with the drain plug fitted, the vacuum created as the housing cools can suck loads of water through the smallest crack. When you replace the belt, silicone the gasket and also the cover plate through which you adjust the timing. Might also be worth considering a breather? Si Link to comment Share on other sites More sharing options...
SHAVED_GORILLA Posted April 18, 2006 Share Posted April 18, 2006 Les, speak to your supplier about it and see if they have a claims procedure with Dayco. I used to work for two local motorfactors and if a product failed we usually dealt with the manufacturer. SG Link to comment Share on other sites More sharing options...
dollythelw Posted April 18, 2006 Share Posted April 18, 2006 Im confused, I always laboured under the assumption that toothed belts dont mind water, Isuzu timing covers leak like a sieve and they are happy, Fenner (they supply me with synch belts) advise theres no problem with running immersed providing nothing too solid gets in the way and mechanically damages the belt and they are kevlar HTD TDP3 60kW belts as used in rock crushers, Link to comment Share on other sites More sharing options...
nas90 Posted April 18, 2006 Share Posted April 18, 2006 I am always amazed at why Land Rover over the years have probably had a handfull of complaints from V8 owners and failed cam drive chains, yet insist on using elastic bands on all the engines they design! with probably zillions of warranty claims for snapped belts Doh! Link to comment Share on other sites More sharing options...
evil90 Posted April 18, 2006 Share Posted April 18, 2006 I had 3 belts go in as many months and they wee all fitted to spec and rechecked after i bit of umming and arring it was decided that the crankshaft pulley was to fault as it had a deep score in it and was sucking water in when hot and getting dunked into cold water as GBMUD and simonr has said above the thing to do is to fit a breather to the case just like an axle breather that is one of my next jobs but for now i have just stayed out the wet stuff and the belt has been fine even after tweaking the pump which would put the belt under more strain and all is well hope yours is the same thing as it is an easy fix but it is frustrating the first couple of times Frank Link to comment Share on other sites More sharing options...
imspanners Posted April 19, 2006 Share Posted April 19, 2006 I think you answered your own question in the original statement Les. The engine hydraulic'd?? That would have been sufficient stress on the timing belt to cause premature failure, in my eyes. (Especially if one of the rods is slightly bent, this could cause a resonance/vibration affecting the belt). Maybe worth doing a compression test? Link to comment Share on other sites More sharing options...
Les Henson Posted April 19, 2006 Author Share Posted April 19, 2006 Well the owner of the vehicle came round this morning (Mark Jenkins of this forum) Busted belt and bent rods etc in hand. The timing belt looked ok, apart from being snapped of course, but the rubber felt strange -more like silicone. Familiar smell from it too - Diesel!!. I unscrewed the timing cover wading plug and approximately 1/2 cup of diesel trickled out. So - injector pump seal failed and leaked diesel into the timing case, The garage that replaced the belt etc should have noticed there was diesel leaking into the case but clearly haven't. The new belt will now need to be replaced as it will too be contaminated. What a shame this has happened, but glad I didn't mess up doing the original job. Les. Link to comment Share on other sites More sharing options...
Turbocharger Posted April 19, 2006 Share Posted April 19, 2006 In which case, Les, I apologise for casting aspersions on your workmanship. Can you remove the hex on my timing belt (and inj pump seals!) now please? Link to comment Share on other sites More sharing options...
SHAVED_GORILLA Posted April 19, 2006 Share Posted April 19, 2006 You can't remove a hex on a Landrover. The only thing you can do now is to sell it but not to a freind as the hexdoubles in power after a change of hands. SG Link to comment Share on other sites More sharing options...
evil90 Posted April 19, 2006 Share Posted April 19, 2006 Well the owner of the vehicle came round this morning (Mark Jenkins of this forum) Busted belt and bent rods etc in hand. The timing belt looked ok, apart from being snapped of course, but the rubber felt strange -more like silicone. Familiar smell from it too - Diesel!!.I unscrewed the timing cover wading plug and approximately 1/2 cup of diesel trickled out. So - injector pump seal failed and leaked diesel into the timing case, The garage that replaced the belt etc should have noticed there was diesel leaking into the case but clearly haven't. The new belt will now need to be replaced as it will too be contaminated. What a shame this has happened, but glad I didn't mess up doing the original job. Les. So belt contamination was the cause just from a different substance i did forget to mention that all the belts i have done had a slimey sort of feel to them when removed so at least now we know there is another seal to double check before putting the timing cover back on. When i removed my wading plug after the belts wnt no water ame out so i assume it turned to steam and the steam weakened the belt which i suppose is another use for the timing cover breather. I suppose the guy will be taking the evidence back to the garage that done the belt Frank Link to comment Share on other sites More sharing options...
geoffbeaumont Posted April 19, 2006 Share Posted April 19, 2006 You can't remove a hex on a Landrover. It'd shear off if you tried Link to comment Share on other sites More sharing options...
Steve H Posted April 19, 2006 Share Posted April 19, 2006 Im confused, I always laboured under the assumption that toothed belts dont mind water, Isuzu timing covers leak like a sieve and they are happy, Fenner (they supply me with synch belts) advise theres no problem with running immersed providing nothing too solid gets in the way and mechanically damages the belt and they are kevlar HTD TDP3 60kW belts as used in rock crushers, Jez, pleased you've brought this up, saved me having to ask. I figured that if anyone had run an Isuzu under water it would probably be you. From reading the whole thread, can I infer then that water will not harm belts especially or should I try to get a belt that can run in such an application? ( I know that shouldn't be an issue with a Land Rover installation, but could be on other brands, such as Isuzus like a few on this forum run) Cheers, Steve. Link to comment Share on other sites More sharing options...
Mark Jenkins Posted April 19, 2006 Share Posted April 19, 2006 Well as you can all imagine I have had an expensive week. But now we know what the reason for belt failure is it is a relatively simple fix. This will be my third timing belt in two months.... grrrr. A bit hacked off that the garage who did the repair didn't spot the fuel leak cos it would have saved me even more hassle and $$$. oh well. arse. Link to comment Share on other sites More sharing options...
dollythelw Posted April 19, 2006 Share Posted April 19, 2006 can I infer then that water will not harm belts especially or should I try to get a belt that can run in such an application? ello Steve mate, no worries with a standard Isuzu belt, run over the cover with a bead of sealant if theres any sizeable gaps that fish and dinghys could get in and start swimming Link to comment Share on other sites More sharing options...
simonr Posted April 19, 2006 Share Posted April 19, 2006 I was lead to believe that the issue isn't so much the water itself, but prolonged exposure to water vapour. In an open timing chest, there is little water vapour, lots of fresh (ish) warm air and the occasional splash of water which soon dries out. In a closed chest, like a LR, the water sits in the bottom, much of it gets vapourised and the belt lives in the vapour until the chest empties by one means or another. I think a breather and removing the drain plug frequently would help a lot. Dave. The reason LR and most other manufacturers gave up using timing chains is the tolerance - or lack of in a chain. It is much easier to meet emissions regs - and get blistering performance - if all the bits of the engine are in sync. Si Link to comment Share on other sites More sharing options...
dollythelw Posted April 19, 2006 Share Posted April 19, 2006 rock crushers run in slurry 24/7, the rubber isnt water permeable and neither is kevlar, I'd be more worried about oil vapour than water - vents are (IMO) a good move, plumbed back to the airbox to create a throughput of cooler cleaner air? synch belts offer a higher maximum line speed than chains (10m/s as opposed to a belt at up to 100m/s) and require minimal maintainance, they can also offer a lower mass for the same power transmission rating - lower valve train mass improves throttle response and frees a couple of extra ponies I found all that info on the back of my cereal box this morning I need sleep Link to comment Share on other sites More sharing options...
simonr Posted April 19, 2006 Share Posted April 19, 2006 the rubber isnt water permeable and neither is kevlar In an ideal world maybe - but the rubber becomes more permiable with use and the kevlar strands, unless protected by something E.g a rubber belt, are affected by water. The strength of the fibres is reduced once they become wet. This is why you almost never see kevlar used on it's own - it's always in resin or with a waterproof coating. You could make a kevlar winch cable about the thickness of a boot-lace with the same tensile strength as an off the shelf dyneema line - but it is just too vulnerable to the environment to make it practical. You do get Kevlar kite line - but it comes with a warning not to get it wet! (unless it's sheathed in spectra, dyneema or similar). Si Link to comment Share on other sites More sharing options...
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