Terminator Posted May 20, 2007 Share Posted May 20, 2007 I have had my car six years now. When I bought it, all you ever heard from both side of the pond, was that the bottom end was indestructible. Many of the big tuning houses in the states use the stock bottom end for big power builds. In most cases the crank is the last thing to be changed as it has a reputation of being so strong. My 1000bhp VWR built lump has a stock crank. As far as I know VWR have a fantastic reputation and have several 8 sec cars on stock cranks I am sure, if my memory is correct, there have been a few crank failures in the UK in quite a short time at relatively modest power levels compared to our American friends. I it got me wondered if the cranks over here are any older than in the US. Then I thought age has nothing to do with it, as most UK MKIV's, (I include both JDM and UK engines) are just as old as in the US. It can't be power levels as few of our cars get close to the USA. I began to wonder if it might be related to a bad batch of JDM cranks. If anyone has had crank failure, it would be helpful if you could use your vin plate to identify the month of manufacture and which plant the car came from. To see if there is a relationship between manufacture and crank failure. Link to comment Share on other sites More sharing options...
Digsy Posted May 20, 2007 Share Posted May 20, 2007 When you say crank failure, do you mean a mechanical failure of the crankshaft itself, or are you talking about associated bottom end components like big end and main bearings? I don't think I've ever heard of a 2JZ crankshaft failing. Link to comment Share on other sites More sharing options...
Terminator Posted May 20, 2007 Author Share Posted May 20, 2007 Sorry I should have clarified, the failures that I referred to, I believe related to main baring failure. Link to comment Share on other sites More sharing options...
Ian C Posted May 20, 2007 Share Posted May 20, 2007 Yeah I've also noticed an alarmingly large amount of crank failures suddenly, when we've had, errr, about zero for five years? What's going on? Are people overrevving them or what? -Ian Link to comment Share on other sites More sharing options...
letmeshowyou Posted May 20, 2007 Share Posted May 20, 2007 what was it that went wrong with James Turner's car in the end? Link to comment Share on other sites More sharing options...
Homer Posted May 20, 2007 Share Posted May 20, 2007 what was it that went wrong with James Turner's car in the end? Lots unfortunately. I think the original failure was down to lack of oil pressure or just wear. The subsequent failures, I don't recall the issues, but I'm sure he's posted details on here when it was finally sorted. Link to comment Share on other sites More sharing options...
Gaz Walker Posted May 21, 2007 Share Posted May 21, 2007 The crank themselves are tough as old boots - its normally the bearings and caps that are the problems (for us anyway!) Gaz. Link to comment Share on other sites More sharing options...
Gamer Posted May 21, 2007 Share Posted May 21, 2007 Dare I say it but could it be because the yanks have a better understanding of what works and what does not with the 2JZ or maybe they make sure that supporting mods are in place such as modified oil pumps and better breather systems. They also tend to have much better or should I say thorough installs/set-up's having spent some serious cash to achieve that. Another factor might be more competent tuners then are available over here. Not trying to start a war but there could be some truth to the above. Link to comment Share on other sites More sharing options...
Bobbeh Posted May 21, 2007 Share Posted May 21, 2007 Not trying to start a war but there could be some truth to the above. Its plainly clear to me they know more about these cars than we do. No harm in stating the obvious Link to comment Share on other sites More sharing options...
Branners Posted May 21, 2007 Share Posted May 21, 2007 probably a question for the tuners....are you seeing more crank failures now than before and have you been able to identify what might be causing them? We always believed the 2jz was bullet proof but the number of failures recently may be changing that view. It would be good if the tuners could let us know their views. JB Link to comment Share on other sites More sharing options...
Ark Posted May 21, 2007 Share Posted May 21, 2007 Yeah I've also noticed an alarmingly large amount of crank failures suddenly, when we've had, errr, about zero for five years? What's going on? Are people overrevving them or what? -Ian There's probably a strong correlation between the incidence of crank failures, and single turbo installations over here. Big singles only really came into vogue over here a couple of years ago. Dare I say it but could it be because the yanks have a better understanding of what works and what does not with the 2JZ or maybe they make sure that supporting mods are in place such as modified oil pumps and better breather systems. They also tend to have much better or should I say thorough installs/set-up's having spent some serious cash to achieve that. Another factor might be more competent tuners then are available over here. Not trying to start a war but there could be some truth to the above. Good points - Dusty came on here one time and pointed out that _most_ yanks buy fuel kits (for example) at the same time as single turbos, basically making the two go hand in hand. We don't, according to his observations. Link to comment Share on other sites More sharing options...
Ian C Posted May 21, 2007 Share Posted May 21, 2007 There's probably a strong correlation between the incidence of crank failures, and single turbo installations over here. Big singles only really came into vogue over here a couple of years ago. Hmmm, but most of us are using stock short blocks like they do. Are these failures unopened short motors or ones that have been cracked open and fiddled with? Good points - Dusty came on here one time and pointed out that _most_ yanks buy fuel kits (for example) at the same time as single turbos, basically making the two go hand in hand. We don't, according to his observations. That might be another factor - doing things on the cheap? The single installs done before the rash of crank failures were generally rather expensive with a lot of labour and a lot of 'named' parts plus all the supporting hardware that was required. Maybe there is something to that. Or is it only single turbo conversions that have gone? I'm not too sure, some trawling through posts needed I guess The loonies like Gaz and Leon are sure to mince an engine or two, with their constant quest for competitive power I think we are talking about the daily driver cars that suddenly have their bearings let go for no apparent reason after years of everything being OK. -Ian Link to comment Share on other sites More sharing options...
paul mac Posted May 21, 2007 Share Posted May 21, 2007 could we not be getting a bit deep here chaps, i think a definate factor has now got to be the age of these motors mine is coming up for 14 years old pushing 500 rwhp i know it aint gonna last forever any engine has a finite life span however well the OEM built it, how ever carefull i am changing oil carbonisation and crud/crap build up is inevitable and oil flows will be getting resticted i am now seriously considering an full engine overhaul before the thing goes bang (winter project) Link to comment Share on other sites More sharing options...
Ian C Posted May 21, 2007 Share Posted May 21, 2007 Good point but I've heard of one person who went through like 4 cranks in about as many weeks Surely they can't have all been stock short blocks swapped in? How unlucky would that have been? I wish I had time to mooch around the site and see what's what but I haven't at the mo. -Ian Link to comment Share on other sites More sharing options...
Chris Wilson Posted May 22, 2007 Share Posted May 22, 2007 Dirt ingress. Link to comment Share on other sites More sharing options...
Wez Posted May 22, 2007 Share Posted May 22, 2007 Poorly setup motors wont last very long Link to comment Share on other sites More sharing options...
Branners Posted May 22, 2007 Share Posted May 22, 2007 Poorly setup motors wont last very long not sure I agree with that in relation to the cranks. I can see that a poorly setup car will either melt a piston or bore wash itself, but not sure poor setup could take out a crank. Chris, what can be done to avoid dirt ingression on the cars? And have you seen any cranks fail in your years of supra work? JB Link to comment Share on other sites More sharing options...
Chris Wilson Posted May 22, 2007 Share Posted May 22, 2007 By dirt ingression I mean dirty engine builds with oilways left unbrushed and old oil left in oil pumps, et cetera, et cetera. I see it all the time on home built race engines, most people have no idea what cleaning an engine for rebuild entails. The only crank failure I witnessed on a JZA80 was due to the customer never checking the oil, and even ignoring the low oil warning light until it was permanently on. Link to comment Share on other sites More sharing options...
Digsy Posted May 22, 2007 Share Posted May 22, 2007 ...so this isn't really crank failure we are talking about but rather bearing failure. I've always said that no matter what else you uprate, bearing geometry is the one thing you cannot change so there has to be a limit to what the stock bottom end will take. My cash would be on lubrication issues and stuff that would affect oil film thickness. poor oil cooling, dirt (as Chris mentioned) etc etc. I also think that age plays a part with bearing clearances opening up. Link to comment Share on other sites More sharing options...
Class One Posted May 22, 2007 Share Posted May 22, 2007 Terrible Turners failure was the shells, and IIRC it was down to poor maintainence by previous owner(s) ie irregular oil changes/servicing and poor quality oil used. His bottom end was full of sludge because his sump filter (correct me if I'm wrong) was clogged with crap,leadin to a loss of oil pressure and subsequent shell failure. I think I recall seeing another failure on here with someones filter completely clogged up. Kind of looked like a pasta sieve with a smokers lung contents in it. Link to comment Share on other sites More sharing options...
Ian C Posted May 22, 2007 Share Posted May 22, 2007 Was Terrible Turner's the one with 4 crank failures? Or am I completely confused? (I'm doing up my new house so on here for about 10 mins at 1am hence my crap responses at the mo ) Terrible Turners failure was the shells, and IIRC it was down to poor maintainence by previous owner(s) ie irregular oil changes/servicing and poor quality oil used. His bottom end was full of sludge because his sump filter (correct me if I'm wrong) was clogged with crap,leadin to a loss of oil pressure and subsequent shell failure. I think I recall seeing another failure on here with someones filter completely clogged up. Kind of looked like a pasta sieve with a smokers lung contents in it. Link to comment Share on other sites More sharing options...
Class One Posted May 22, 2007 Share Posted May 22, 2007 Was Terrible Turner's the one with 4 crank failures? Or am I completely confused? (I'm doing up my new house so on here for about 10 mins at 1am hence my crap responses at the mo ) His first one was deffinately down tothe sluge issue/blocked filter as mentioned. Link to comment Share on other sites More sharing options...
Ian C Posted May 23, 2007 Share Posted May 23, 2007 I suppose the next question is then, if a crank bearing failure has occurred, then: a) was it a 'rebuilt' engine? b) if it wasn't, how many miles did it have on it and was it well serviced/maintained? c) what power was it putting out and how was it driven? That'd narrow down the causes and maybe offer some peace of mind to people? I'd like to think if it was only rebuilt or coked up engines that ate their shells then I'm safe -ian Link to comment Share on other sites More sharing options...
francis Posted May 23, 2007 Share Posted May 23, 2007 American's change their engine oil almost as regularly as they fill up their fuel tanks, there are special garages that just do drive through style oil changes and it's not a big deal like it is here.. Could this be a factor? Also as far as I'm aware they're only allowed US supplied Supes over there so presumably most will have fully documented history . Most of the Supe's I've seen in the states have been immaculate. Link to comment Share on other sites More sharing options...
Digsy Posted May 23, 2007 Share Posted May 23, 2007 Is oil as cheap as petrol in the US? Link to comment Share on other sites More sharing options...
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