Mavota Posted March 16 Report Share Posted March 16 Hi All, Last month I posted about my car break down and a potential flywheel issue: Well, the mechanics have finally got the engine opened up and it turns out the issue was my crank thrust washer (I’d never heard of it till today). It has split in two, with one half falling into the sump. Fragments of metal have come off into the oil and circulated round the engine. So the whole engine is F*CKED. I had a non-standard Sachs SRE clutch and pressure plate fitted last August, so VW think the warranty company will refuse to cover anything. Even if they do, the max on a used car warranty is apparently £5k. The cost to fix is expected to be £10k. Regards from a rather upset Mavota Quote Link to comment Share on other sites More sharing options...
gregozedobe Posted March 17 Report Share Posted March 17 I know it doesn't help you, but I have read a lot of people fit an upgraded rear main seal (RMS) when fitting an upgraded clutch. It seems the stock VW RMS is somewhat failure prone, especially with the extra stress from an upgraded clutch. Quote Link to comment Share on other sites More sharing options...
fastandy Posted March 17 Report Share Posted March 17 23 hours ago, Mavota said: Hi All, Last month I posted about my car break down and a potential flywheel issue: Well, the mechanics have finally got the engine opened up and it turns out the issue was my crank thrust washer (I’d never heard of it till today). It has split in two, with one half falling into the sump. Fragments of metal have come off into the oil and circulated round the engine. So the whole engine is F*CKED. I had a non-standard Sachs SRE clutch and pressure plate fitted last August, so VW think the warranty company will refuse to cover anything. Even if they do, the max on a used car warranty is apparently £5k. The cost to fix is expected to be £10k. Regards from a rather upset Mavota Yeah. That's some pretty bad Friday news. 😔 So, it's potentially all drivetrain related but I could not say if it is upgraded clutch related or not. The clutch, flywheel, crank thrust washer, they're all in line and involved in connecting engine motion, through to transmission. Unlike clutch and flywheel which are external to the engine casing itself, the thrust washers limit end play movement of the crank, inside the engine itself. As you've discovered that is really bad news yours has broken up. I'm not sure how likely the clutch is to have caused this, there are other possibilities as well. You may want to create a new thread reading say "Upgraded clutch, engine failure. Edit: clutch Related?" In the modifying mk7 section see what you get back in terms of sachs or other uprated clutch experiences . That's a lot of money, if they offer you nothing under warranty, it may be worth getting engineering advice and inspection and fight it under consumer rights act if previous owner damage or poor engineering or assembly are more likely than the upgraded clutch. I'll do some googling see if I see much on failed thrust washers. I can't recall hearing about one in a golf r before (seat leon cupra 300/310, audi s3 around same vintage, share same engine) Quote Link to comment Share on other sites More sharing options...
fastandy Posted March 17 Report Share Posted March 17 2 hours ago, gregozedobe said: I know it doesn't help you, but I have read a lot of people fit an upgraded rear main seal (RMS) when fitting an upgraded clutch. It seems the stock VW RMS is somewhat failure prone, especially with the extra stress from an upgraded clutch. Agree RMS is a vulnerability. But it's not driveline pressure, force, related it's engine crankcase gasses pressure related no? Edit. As well as durability poor - wearing badly on the original part. Quote Link to comment Share on other sites More sharing options...
fastandy Posted March 17 Report Share Posted March 17 It seems you're not alone and the words "usual" suggest it is more widespread than i realised and in this case, the upgraded clutch makes the vulnerability worse. Edit: lots of posts on the golfmk7 boards. Comments by users are split as to whether the aftermarket clutches are the real cause, the failure can and does affect stock clutches as well. But an upgraded clutch makes it significantly more likely you'll have a problem. That's how I digest all this anyway. Others opinions may vary. https://www.golfmk7.com/forums/index.php?threads/the-usual-thrust-bearing-failure.394106/ https://www.golfmk7.com/forums/index.php?threads/crank-walk-class-action-we-need-to-get-together.371168/page-2 https://www.golfmk7.com/forums/index.php?threads/what-causes-thrust-bearing-failure.366981/ Quote Link to comment Share on other sites More sharing options...
Mavota Posted March 19 Author Report Share Posted March 19 (edited) Greg – Yea, on the other thread Growmac recommended I get the Rear Main Seal replaced while I had the car in. Too late unfortunately. Is the Rear Main Seal the same thing as, or part of, the Crank Thrust Washer? Andrew – Thanks for the info and links. I noticed in one of the threads that VW revised the thrust bearing in December 2017 – my car is January 2017. Do you have any idea how I might go about getting independent engineering advice and inspection? One of the threads is about “Crank Walk” and a potential class action. Is crank walk related to the crank thrust washer? From the stats in that thread it looks like cars with upgraded clutches are far more likely to have the issue. Probably not great news for me. Lesson learnt for me: I don’t know enough about cars to get non-standard parts fitted. Next time I have an issue with a car that can’t be fixed with OEM parts, I should sell the car and get a new one. Edited March 19 by Mavota Quote Link to comment Share on other sites More sharing options...
Mavota Posted March 19 Author Report Share Posted March 19 Ok, one thing I’d like you guys’ thoughts on. How long after the crank thrust washer fails does it take for the circulating oil to bugger up the engine? Long story short: When my car broke down last month I turned it off immediately. I believe that was the moment the crank thrust washer broke (I was feathering the clutch and then bam, something went wrong). Nobody drove the car again until after it had been to an approved VW dealership. They said there was nothing obviously wrong with the car, and released it back to me as safe to drive. I’m thinking the engine block would not have been harmed if VW had not told me it was fine to drive…? Quote Link to comment Share on other sites More sharing options...
fastandy Posted March 19 Report Share Posted March 19 2 hours ago, Mavota said: Greg – Yea, on the other thread Growmac recommended I get the Rear Main Seal replaced while I had the car in. Too late unfortunately. Is the Rear Main Seal the same thing as, or part of, the Crank Thrust Washer? Andrew – Thanks for the info and links. I noticed in one of the threads that VW revised the thrust bearing in December 2017 – my car is January 2017. Do you have any idea how I might go about getting independent engineering advice and inspection? One of the threads is about “Crank Walk” and a potential class action. Is crank walk related to the crank thrust washer? From the stats in that thread it looks like cars with upgraded clutches are far more likely to have the issue. Probably not great news for me. Lesson learnt for me: I don’t know enough about cars to get non-standard parts fitted. Next time I have an issue with a car that can’t be fixed with OEM parts, I should sell the car and get a new one. The rear main seal stops engine gasses and oil escaping the crankcase. It is a seal on the end of the crankshaft bolted onto the outside of the crankcase housing on the transmission end of engine. Opposite end to where crank pulley, drive belts are visible in engine bay. You cant normally get to it or see it without transmission removed. You need to remove the transmission to do the clutch, or flyweel hence the commemts and suggestions. The thrust bearing or washer inside the engine next to one of the main bearings keeps the crankshaft end play movement in check. Not related apart from both to do with the crankshaft. They're not the same problem. In the context of the postings used in na forums, crank walk is the same thing as thrust bearing failure. It shows crank moving out of alignment "walk" when the clutch is engaged pulling the crankshaft out of its normal alignment by several mm or more. Sometime 1/2inch or more. You've been unlucky. And it is a vulnerability of the car design, even the clutch interlock, pressing clutch to start is said the meaningfully contribute to the issue along with the bearing design, materials. If some one rode the clutch before your purchase, that could of created the conditions for start of the problem. The heavier pressure clutch will have made it worse, eventually destroying the bearing. Of course, if it was clear warranty without modified parts you'd not be as worried about escape clauses. Doesn't help, now I know. I wouldn't be too hard on yourself, it's one of those, you don't know what you don't know. This is only really an issue for manual transmission Rs as well. Quote Link to comment Share on other sites More sharing options...
fastandy Posted March 19 Report Share Posted March 19 2 hours ago, Mavota said: Ok, one thing I’d like you guys’ thoughts on. How long after the crank thrust washer fails does it take for the circulating oil to bugger up the engine? Long story short: When my car broke down last month I turned it off immediately. I believe that was the moment the crank thrust washer broke (I was feathering the clutch and then bam, something went wrong). Nobody drove the car again until after it had been to an approved VW dealership. They said there was nothing obviously wrong with the car, and released it back to me as safe to drive. I’m thinking the engine block would not have been harmed if VW had not told me it was fine to drive…? That's the million £ question. Most forums in us of a suggest a short block replacement - at least. That's the assembled lower part of the motor including crank, crank case, connecting rods, pistons, rings. The "bottom end" of the engine. Here, I suspect vw will use a complete remanufactured engine, without ancillaries like turbo, alternator etc, these to be swapped. The trouble is from the moment the crank started to move out of alignment on clutch pedal press, it's been doing damage. That was well before the washer dropped into the pan. The crank and crank case and bearings will be damaged certainly. Then you've got risk of oil filling contamination elsewhere. Which might not be a problem, but who knows. The car may have had out of tolerance crank endplay at the time, the new clutch was put in. Indicating it was stuffed already. If you're guy is not aware of the issue he probably didn't check it. But we can't travel back in time now. This information on the motor industry ombudsman might be useful as it gives name of 2 industry engineering inspection firms who can prepare reports. But equally if you know an experienced garage with experience of these engines who understands the problem they could equally write a report as to their believed root causation. https://www.themotorombudsman.org/consumers/independent-vehicle-reports Quote Link to comment Share on other sites More sharing options...
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