[hardcore_cobra]

There seems to be quite a few oil leak threads recently. Anyway, I hope this doesn't get too long. When I bought my Mk3 it had 150k mile on the original head gasket. There was an oil leak which appeared to be coming from the head gasket on the intake side and leaking down the side of the block. It still ran fine and no other signs of a BHG so I bought it with the plan of changing the HG out.

I tore the head off and to my surprise the head gasket looked like it was in very good shape. There were no signs of it being blown, or why it would be leaking either now that I come to think of it.

At any rate, I replaced the HG and got it all back together. After my first drive, I have the same puddle of oil under the car. The block under the intake is again covered with oil. What else could be leaking on the intake side of the block? It's so wet I can't determine where it's coming from.

Any ideas? Is there a something common?

 

[Trent]

Can you tell if its in the front or in the back at least?

If its in the front, then I'm willing to be its the hose that goes from the block up to the side of the intake side valve cover. That hose is exposes to a lot of heat being where it sits and will harden up and crack over time. I replaced mine at least once when I had mine.

 

[hardcore_cobra]

Can you tell if its in the front or in the back at least?

If its in the front, then I'm willing to be its the hose that goes from the block up to the side of the intake side valve cover. That hose is exposes to a lot of heat being where it sits and will harden up and crack over time. I replaced mine at least once when I had mine.

Hmmm.... you know... that hose is hard, brittle, and cracked slightly at the top where it goes into the cam cover. I can't tell if it's from the front or back because it's just so wet. But, it could be blowing back from the wind. Anyone know the Toyota part # off the top of their head? I'll start looking.

 

[aaronc222]

12263-42010

 

[mk3_ftw]

this may be newbish but isnt it just 5/8 in size? in that case just go get 5/8 heater hose from a parts store and use that. just a though i could be wrong

 

[LHargrove]

this may be newbish but isnt it just 5/8 in size? in that case just go get 5/8 heater hose from a parts store and use that. just a though i could be wrong

If you do something like that, better make sure the hose is rated for oil.

 

[Trent]

this may be newbish but isnt it just 5/8 in size? in that case just go get 5/8 heater hose from a parts store and use that. just a though i could be wrong

It's either a 5/8" or 3/4" but it makes some pretty sharp turns and needs to snake around a few things to take the shape that it does. I'm not saying its not possible, but it may require a hose already bent to that shape to keep a standard heater hose from kinking and not working properly.

 

[mk3_ftw]

ok i wasnt sure. im going to replace this hose soon anyway since i got the top end all apart and it was just something that occured to me

 

[hardcore_cobra]

Because this hose was cracked slightly on top, I'd looked into replacing it already, just hadn't done it. It's got to be molded because of the way it sits in next to the alternator. Local Toyota dealership wants $35 and will have it tomorrow. I found it for $25 online, but I'll just pay the extra $10 and pick it up in the morning.

Hope this fixes it. If not, it really should be replaced anyway.

 

[sixpack]

Seeing how many miles it has, I suggest you go from one end of the breather system, to the other,
(cam covers to throttle body)
and make sure it's all open.
I have seen several 7Ms glue the breathers, little tubing manifold, or the pipe in the throttle body completely shut with crud.
Then your crankcase builds pressure, and pushs oil out at what ever is the weakest seal or gasket.

 

[hardcore_cobra]

12263-42010

BTW, how do you do that so quickly? I've got the TSRM bookmarked, but I must either absolutely suck at finding this shit in there or you guys get it somewhere else. Teach this man to fish so I can quit askin for part #s lol.

Seeing how many miles it has, I suggest you go from one end of the breather system, to the other,
(cam covers to throttle body)
and make sure it's all open.
I have seen several 7Ms glue the breathers, little tubing manifold, or the pipe in the throttle body completely shut with crud.
Then your crankcase builds pressure, and pushs oil out at what ever is the weakest seal or gasket.

Will do. Most of it has been replaced because of dry rot and cracking anyway. The line in question was going to be replaced, but I got impatient... gotta stop doing that.

I've still got a few other issues to sort out I'll be working on tonight.

 

[adidas00]

bad valve cover gasket?

 

[bigsupraman66]

That actually just happened to me. I replaced the PVC hose. But, I saw my Valve cover was cracked near the back of the engine. So, could of been that. I don't know I'll let you know how mine goes.

 

[hardcore_cobra]

Cam cover gaskets are new and don't appear to be leaking. There's no oil above the lower runners. It's likely that vent tube on mine, will know tomorrow.

 

[mk2racer]

Cam seals, not cover gaskets, were my problem. Take off the timing cover and look behing the timing gears while the motor is running. I could NEVER see where it was coming from, but always had a puddle, finally found it. Easy to replace too, mark the gear, one bolt and it pops off, pry the old one out carefully and slide the new one it. Piece of cake.

 

[SrBigbutt]

Cam seals, not cover gaskets, were my problem. Take off the timing cover and look behing the timing gears while the motor is running. I could NEVER see where it was coming from, but always had a puddle, finally found it. Easy to replace too, mark the gear, one bolt and it pops off, pry the old one out carefully and slide the new one it. Piece of cake.

Is it really that simple? I just noticed mine was slightly leaking from around that area and i'm pretty sure its the cam seals. I will have to investigate and fix it.

 

[bigsupraman66]

Becareful about putting them in. If the rubber gets chipped or ripped in anyway. Your screwed. Plus, try to stay away from the cheap autozone ones or you'll replace them more often. I did mine twice due to wrong parts. Well, glad to hear the good news.

 

[SrBigbutt]

Thank. If they are leaking I would definately get Toyota parts. I can get them for about the same price as the cheap autozone ones anyway.

My car has leaked every type of fluid their is! This is the one of the last leaks that I can tell.

 

[bigsupraman66]

Yeah, I think anybody with a supra has done this or gonna eventually. Supra's are so much fun.

 

[hardcore_cobra]

Oh yeah, guess I should update for people reading later. Got a new vent hose from Toyota. Put it on, clamped it down, stopped the leaking down the side of the block.