Mike B Posted February 3, 2015 Share Posted February 3, 2015 Always something new to learn. I knew that any residual pressure was bad, but I didn't know it could have such terminal effects. Going to check mine again! I note that Ryans map on my car has it crank at least 7 times before the ignition fires. Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted February 3, 2015 Share Posted February 3, 2015 That'll help rod and main bearings as it should be well on the way to pumping oil everywhere by then, but if the thrusts are compressed hard against the thrust face of the crank oil can't escape and lubricate the faces. They need a running clearance for the oil film to establish itself within, BEFORE clutch thrust is applied. A stock clutch probably won't apply enough pressure to overcome oil seepage, but race clutches involve far greater thrust loads. Quote Link to comment Share on other sites More sharing options...
wattwatt Posted February 3, 2015 Share Posted February 3, 2015 That's just for a short duration, but still bad practice. With no end float in the clutch release it's like driving with pedal permanently depressed a bit *ALL THE TIME* the engine's running! I always do this it's force of habit, due to working at Toyota and ALL of the new models physically won't start without the clutch pushed down. I now do it in any car without even thinking including the supra ?? Quote Link to comment Share on other sites More sharing options...
Brazil Posted February 3, 2015 Author Share Posted February 3, 2015 That'll help rod and main bearings as it should be well on the way to pumping oil everywhere by then, but if the thrusts are compressed hard against the thrust face of the crank oil can't escape and lubricate the faces. They need a running clearance for the oil film to establish itself within, BEFORE clutch thrust is applied. A stock clutch probably won't apply enough pressure to overcome oil seepage, but race clutches involve far greater thrust loads. But Chris, is it really possible for this to happen with an engine with such few mileage? The oil pressure issue started after the base map for running in the new engine, I left the car for 1 month while we waited for the new diff and when I picked it up all the oil pressure problem happened straight away after pulling car out of shop. Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted February 3, 2015 Share Posted February 3, 2015 I can only say it as it is, and that's that I cannot think of any other reason for the thrust washers to be ejected like that. Bear in mind it's new bearings on a used crank, and these things take time to bed, with no oil film the thrusts would get hot spots and try and solder themselves to the crank or pure friction will move them out of place. I am told this is a far from unknown issue on 2JZ's in the USA and is mentioned on the US Supra forum, of which I am not a member. Get the engine out, pull the upper sump casting, and pull the main cap that holds the thrusts and let me see what state it's in. It's the cap that holds the tangs of the lower thrusts, and these then stop the upper ones turning. Have you found four or just two thrusts, I am not sure from the photos? If the cranks walked about that would also explain your front seal leak. The oil pump may be knackered, if the crank has moved forward enough to push on the pump's rotor. Actually, I think the Americans call thrust washer failure or abnormal wear "crank walk". As I said, I'll help as much as possible! Quote Link to comment Share on other sites More sharing options...
Brazil Posted February 3, 2015 Author Share Posted February 3, 2015 I can only say it as it is, and that's that I cannot think of any other reason for the thrust washers to be ejected like that. Bear in mind it's new bearings on a used crank, and these things take time to bed, with no oil film the thrusts would get hot spots and try and solder themselves to the crank or pure friction will move them out of place. I am told this is a far from unknown issue on 2JZ's in the USA and is mentioned on the US Supra forum, of which I am not a member. Get the engine out, pull the upper sump casting, and pull the main cap that holds the thrusts and let me see what state it's in. It's the cap that holds the tangs of the lower thrusts, and these then stop the upper ones turning. Have you found four or just two thrusts, I am not sure from the photos? If the cranks walked about that would also explain your front seal leak. The oil pump may be knackered, if the crank has moved forward enough to push on the pump's rotor. Actually, I think the Americans call thrust washer failure or abnormal wear "crank walk". As I said, I'll help as much as possible! How is it possible to engineer the motor so this does not happen again? Is it worth changing the clutch all together? Quote Link to comment Share on other sites More sharing options...
JamieP Posted February 3, 2015 Share Posted February 3, 2015 Clutch is fine. I very much doubt it's anything to do with the clutch as you had issues from first start on base map. Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted February 3, 2015 Share Posted February 3, 2015 If the clutch and pedal is adjusted so there's free play it won't be an issue. Plus always start the car in neutral, without your foot on the clutch. Clutch is top quality, it will have been an adjustment thing, I am sure. If you are paranoid you could look at Accusumps. They store pressurised engine oil and inject it back into the engine's oil galleries before starting, or if oil surge drops pressure. Downside is where to put it (it's big) and yet more plumbing and stuff to go wrong. How many thrusts have you fished out of the sump? Quote Link to comment Share on other sites More sharing options...
Swampy442 Posted February 3, 2015 Share Posted February 3, 2015 If you are paranoid you could look at Accusumps. They store pressurised engine oil and inject it back into the engine's oil galleries before starting, or if oil surge drops pressure. To be honest Im surprised this wasn't introduced on engines years ago. Quote Link to comment Share on other sites More sharing options...
j_jza80 Posted February 3, 2015 Share Posted February 3, 2015 To be honest Im surprised this wasn't introduced on engines years ago. It's not really necessary on most engines at factory specs. Many engines, including the Toyota JZ family, have proven to generally outlast the cars they're fitted to. Quote Link to comment Share on other sites More sharing options...
Brazil Posted February 3, 2015 Author Share Posted February 3, 2015 If the clutch and pedal is adjusted so there's free play it won't be an issue. Plus always start the car in neutral, without your foot on the clutch. Clutch is top quality, it will have been an adjustment thing, I am sure. If you are paranoid you could look at Accusumps. They store pressurised engine oil and inject it back into the engine's oil galleries before starting, or if oil surge drops pressure. Downside is where to put it (it's big) and yet more plumbing and stuff to go wrong. How many thrusts have you fished out of the sump? Only two thrusts were found dislocated.. Quote Link to comment Share on other sites More sharing options...
RobUK Posted February 3, 2015 Share Posted February 3, 2015 Feel for you! I went through the same thing last year and LeeP sorted my car out... Mine was due to the Clutch too... Pics to follow.... Quote Link to comment Share on other sites More sharing options...
Mike B Posted February 4, 2015 Share Posted February 4, 2015 and the irony is my wife's golf 2.0tdi will not start unless you put your foot on the clutch. Big message on the dashboard *depress clutch to start* though I'd like to think they have engineered their own solution. Quote Link to comment Share on other sites More sharing options...
Luxluc Posted February 4, 2015 Share Posted February 4, 2015 and the irony is my wife's golf 2.0tdi will not start unless you put your foot on the clutch. Big message on the dashboard *depress clutch to start* though I'd like to think they have engineered their own solution. My uncle's old Pontiac TransAm was the same. Quote Link to comment Share on other sites More sharing options...
Brazil Posted February 4, 2015 Author Share Posted February 4, 2015 If the clutch and pedal is adjusted so there's free play it won't be an issue. Plus always start the car in neutral, without your foot on the clutch. Clutch is top quality, it will have been an adjustment thing, I am sure. If you are paranoid you could look at Accusumps. They store pressurised engine oil and inject it back into the engine's oil galleries before starting, or if oil surge drops pressure. Downside is where to put it (it's big) and yet more plumbing and stuff to go wrong. How many thrusts have you fished out of the sump? Chris another thing to note is that my oil pressure at first start up when cold was 3.5 bar thats before even it was engaged in gear, i have read some people here saying that there idle pressure is 7 bar when cold? that is a big difference. Quote Link to comment Share on other sites More sharing options...
Tyson Posted February 4, 2015 Share Posted February 4, 2015 pretty sure that my supra owners manual tells me to start it with the clutch depressed !! Quote Link to comment Share on other sites More sharing options...
Alex Posted February 4, 2015 Share Posted February 4, 2015 (edited) and the irony is my wife's golf 2.0tdi will not start unless you put your foot on the clutch. Big message on the dashboard *depress clutch to start* though I'd like to think they have engineered their own solution. pretty sure that my supra owners manual tells me to start it with the clutch depressed !! It's to idiot proof the car from people that leave it in gear. With a stock pressure clutch correctly installed. Luiz's clutch was *probably* putting pressure into the engine when the engine was running *no matter if the pedal was depressed or not*. Its this constant pressure from an extreme clutch that's the key here. Edited February 4, 2015 by Alex (see edit history) Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted February 4, 2015 Share Posted February 4, 2015 It's to idiot proof the car from people that leave it in gear. With a stock pressure clutch correctly installed. Luiz's clutch was *probably* putting pressure into the engine when the engine was running *no matter if the pedal was depressed or not*. Its this constant pressure from an extreme clutch that's the key here. Yes, that's precisely it, thanks Alex! Quote Link to comment Share on other sites More sharing options...
Brazil Posted February 4, 2015 Author Share Posted February 4, 2015 Yes, that's precisely it, thanks Alex! In regards the oil pressure Chris; when I first started the car the idle pressure was 3.5 bar, at first I though it was due to where the sensor was located but later I did a test with a mechanical gauge from block to vvti line 'closed' off and it read same pressure as the syvec guage. Why do you think that my oil pressure from first instalation was only 3.5 bar at idle when cold when everybody else seems to have between 7 to 10 bar? Quote Link to comment Share on other sites More sharing options...
JamieP Posted February 4, 2015 Share Posted February 4, 2015 My cold start was about 10 bar on the black beast. Quote Link to comment Share on other sites More sharing options...
Ian C Posted February 4, 2015 Share Posted February 4, 2015 That's just for a short duration, but still bad practice. With no end float in the clutch release it's like driving with pedal permanently depressed a bit *ALL THE TIME* the engine's running! I think I have the opposite, I have to put the clutch down almost to full pedal travel to get lower gears, especially if the 'box has gotten hot! Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted February 4, 2015 Share Posted February 4, 2015 (edited) I just don't know, I spoke to Ryan at the time, about you saying it was stalling after coming off the throttle and he didn't seem to have any concerns about the oil pressure. He said it was a mapping issue and he'd correct it. I don't see that much cold pressure on newly built engines, I'd be concerned if I did, 150 PSI is likely to burst an oil filter canister! I am sure if the mapper saw low oil pressure he wouldn't have had you run it at 1.2 Bar boost on the dyno, with flames coming out the screamer pipe, the same day it had a base map in it If you are implying the thrusts were left in the sump from the start I can assure you the engine wouldn't have done 1000 miles, or made that sort of boost without doing something very dramatic A cold *IDLE* oil pressure, of nearly 150 PSI is ridiculous, are you sure people are not saying a cold *RUNNING and REVVED UP* pressure of 10 Bar? Edited February 4, 2015 by Chris Wilson (see edit history) Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted February 4, 2015 Share Posted February 4, 2015 My cold start was about 10 bar on the black beast. That sounds a lot, here is what Fram say: http://www.fram.com/media/7087/overpressurized.pdf 150 PSI is up in the deform the filter canister region. Quote Link to comment Share on other sites More sharing options...
JamieP Posted February 4, 2015 Share Posted February 4, 2015 I never had an issue with the engine, maybe dodgy gauge. I've not got one on the goose to check. Quote Link to comment Share on other sites More sharing options...
Mgrene Posted February 4, 2015 Share Posted February 4, 2015 I'm also running around 8 bar on cold start. Just changed my gauge, will check again in two weeks time if it reads the same. Quote Link to comment Share on other sites More sharing options...
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