Oil Leaks: what and where can they happen?

[CampbellsChunkySoupra]

I want to run my supra at the local strip and i am afraid of getting booted while waiting in the stageing area due to dripping a few spots of oil. with that said:

Ive recently replaced my valve cover gaskets and all of the hardware that holds them down. i have also replaced the o'ring that is on the CPS. so now all of my leaks are gone from the valve cover region of the motor. doing that, cleaned up the burning of oil under the hood.

i still drip some oil [not alot] when the car sits still. it is really not alot of oil, but if the car is sitting at the track for 20 minutes at a time waiting my turn, it could make a small spot. im curious as to what else could be dripping oil.

my engine bay is covered in some oil grime and sludgy crap because i have not been able to find the entire leak and keep the engine bay clean.

when i look under the car, it looks like it is dripping from the "frontisht" of the engine. closer to the front of the oil pan or so. i cant see the exact cause of the leak because it drips slowly and it seems like it just drips off of other parts.

oil pan seal/gasket? what else is a common "leaker" of oil on our 7m-gte's?

-Tyler

 

[BJ91T]

not sure about the front of the motor mine just dumps oil from the rear main.
I would first give the motor a good cleaning that will make spotting leaks much easier. Mine also had a leak on the oil cooler fitting coming from the pan when the car sat it would drip on the x member and roll to the front of it took me a while to find that.

Super Clean white package BTW!!!!

 

[super.secret.supra.club]

check the gasket behind the timing belt under the car and in front of the valve cover...

 

[jdub]

^^^ He's referring to the front main and two cam seals.

 

[mkiiSupraMan18]

^ Don't forget the oil pump shaft seal.

Oil pan, oil pan drain plug, Oil Filter, oil filter mount, oil lines coming off the mount, oil line coming off of the oilpan, oil lines on the turbo... There are a lot of spots that oil can leak out of.

 

[CampbellsChunkySoupra]

awesome thanks! we'll check them out this weekend.

 

[mkIIIman089]

Be sure to report back. I've also got some possible issues with my front main, oil pump drive seal and oil pan. (Mine won't drip ever, just leaves a nice coat on the undercover.)

 

[Halsupramk3]

I just went thru a 3 time engine pull to fix oil leaks. one pull to fix rear main seal. still had leaks to pulled 2nd time to replace trans seals. still had leak and pulled the engine a third time to replace oil pan gasket. still leaked. i had oil from about the middle of the oil pan gasket on the passenger side rearward to the trans support and the oil went down it to the trans mission and into the bellhousing and down the down pipe. it would burn off on the pipe. i had oil mess all down the trans and drive shaft. really pissed me off. it leaked so much i really could not drive the car. nothing fixed it. I took off the engine mount on the passenger side and it looked like my dip stick may have been leaking. i didnt see why as it had a new o ring on it. I igot a extra upper tube and noticed it had a different size o ring. when i had my engine down for two years i forgot how the tubes went together. I had put a o ring on the tube that went over the bell shape of the block tube hole. that way the tubes just had one tube on top of the other. i just forgot to insert the upper down into the lower tube with the small o ring. when i put a correct o ring on it and inserted the upper into the lower tube no more leak. what a way to waste time pulling engines three times to just replace a $3 o ring from toyota to stop the leak.

areas i found leaks in the past

1 o ring in dip stick tube and top tube must be inserted into lower tube.
2 o ring on cps. leaks out from cps hole in head
3 seal inside cps leaks out of cover on cps
4 cam cover gaskets. dont forget to retorque bolt on cover after a few heat cycles
5 cam seals/oil shaft seal.
6 front main seal or rear main. rear is common
7 bolt on PS side of lower timing cover must be sealed with silicone. this bolt goes into block and has access to oil. see pic
8 oil pan gasket.
9 oil cooler lines must be tight and not hard rubber.
10 oil mount has o ring under it but rarely leaks.
11 oil return tube from turbo to block
12 oil feed tube to turbo at/underneath turbo

probably the cps and cam cover are the most common then rear main, front seal, and last oil pan gasket. the union on top of the PS pump can be a leak but is red fluid. the high preasure ps line can leak too.
i did have to reseal the bolt on the lower tiiming cover. see pic of where all the oil can go from this leak. the front seal did not leak. that oil leak went a lot of places from its source when it hit the crank and belts.

it is so nice to not have oil leaks.

 

[BJ91T]

Hal is that oil/dirt i see on your motor ?? oh no i need to save that picture im pretty sure its the only time i will ever see that again....untill i look at my motor that is

Thanks for all the help with mine By the way

later
BJ

 

[gixxer750]

Right click... save as.


I've got the worst leak ever(not really, just the hardest to fix) mine leaks between the block and the head.. oil that is, right into the timing cover.

Oh, and Hal....why is the snout of the crank rusty. should be clean and anti-seized

 

[Halsupramk3]

thats a pic when my balancer was wobbling around on the snout and ruining my crank. i did put some anti sieze on the snout before instalation but the when the balancer was getting looser and looser i think some oil went under there too.

 

[CampbellsChunkySoupra]

WOW! definatly have some more options to look for oil leaks now. looks like i have a project ahead of me to troubleshoot and find the leak. the first step this week is to "degrease" and pressure wash the engine bay so i can get it all cleaned up so i can maybe start looking for the leak. then ill just let it idle and watch on the ground for awhile and then look up and find it. hopefully it will be that easy.

how hard is it to replace the o ring on the dipstick? do u have to do anything special? do u reach it from above or below the car?

thanks for all the replys guys.

-Tyler

 

[BJ91T]

un bolt the dipstick from the bracket on the turbo and pull it out from the top i would assume i just did mine that way....but that was not my leak

 

[Halsupramk3]

the dip stick leak i had was hard to diagnose because it did not leak when idling. the larger than original o ring i had on the end of the upper tube fit on top of the lower tube that goes into the block. that made my overall length of the tube longer by about 1/2 inch and i put about half a quart more oil in to read the same level on the stick. not a big deal but the oil (thin synthetic) would blow out at operating speeds 3000 rpm. the tube is hidden behind the turbo bracket support and 1990 motor mount. it is hard to see but i could see oil in the recessed bolt positions on the motor mount. i could also see oil on the bottom of the mount and continuing to the oil pan and down the seam of the oil pan to the trans bracket and then to the trans. i also have a small leak from the corner of the valve cover but could not tell how much was coming out there. i thnk very little. when i removed the motor mount off the block the lower tube did not look oily like everything else so i did not think it was the source. but it was.

as mustangman05 (dont know why he is a mustangman since i never see a mustang at his house but only 3 supras) mentioned just unbolt the stick, pull it out of the lower tubes hole, install a new soft o ring (original gets hard) and reinsert into lower tube. It will go into the lower tube hole about 1/2 inch to seal out oil. then bolt back to turbo location on upper half. reinsert stick and check oil. dam o ring is about $2 from toyota because it is a weird size.

get a mirror on a stick and a flashlight to check up under and around the engine. the oil return pipe from the turbo to the block can leak and also the oil feed into the turbo can leak. i bet that when you clean it all off and drive around at slow speeds a little bit then look you will find it.

 

[CampbellsChunkySoupra]

ive got a set of cam seals. im going to order the front main seal just be safe anyways. preventative maintainence as well as narrowing down the cause.

 

[3p141592654]

If you replace those then also replace the oil pump drive seal at the same time.

 

[toyo4life]

If you replace those then also replace the oil pump drive seal at the same time.

I'm having this same problem now . The oil pump shaft seal keeps pushing out. I think I've narrowed it down to a problem in my PCV system.
Can anybody confirm this, when you remove the oil cap while idling on a properly functionig PCV system, Your idle should stumble a bit right?

 

[kapkaniMD]

Hey guys, Im having a similar problem. I just got my supra and the only time it leaks is after it gets driven pretty good. This is a newly rebuilt engine so It could be anything at this point. It appeared to becoming from the CPS but there didnt appear to be any oil in the CPS cover. So I removed it only to notice no O-ring at all. I put a generic on in from a autoparts store and gave it a test run, but the car still leaked just not as bad... Im wondering if I need a bigger O-ring or maybe it is coming from somewhere else. Does anybody have any dimensions for the right fit O-ring for the CPS. ie. OD, ID and thickness???

 

[7Mboost]

Push car through staging lanes.

 

[jtran8]

don't forget to check the turbo oil feed and return line that hook to bottom of turbo . alot of time oil leaks from there , the higher rpm the more oil pressure .:naughty: