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SRD to the rescue...!


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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.

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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!

 

:blink: 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 ??

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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.

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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!

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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?

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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?

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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..

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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.

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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.

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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 by Alex (see edit history)
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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!

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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?

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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!

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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 by Chris Wilson (see edit history)
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