I've had a slow oil leak on this 4Runner for as long as I've owned it (About 6 months). But today, that leak got significantly worse. Currently at a rate of 2-3 drops a second hitting the ground at idle. It looks like it's coming from the head gasket, but I can't quite seem to make that make sense. Cam cover gaskets are good, timing cover gasket is good. I've taken some pictures that I will include to this post. I appreciate the help!

 

If you want to be sure add some UV dye into the system.

 

I'd suggest you get a can of spray degreaser and a garden hose to clean up that area. Once you get it sparkly-clean, the source of the leak should be pretty clear.

Don't forget that gravity is not your friend. It is always possible to have a leak higher in the engine, and gravity pulls everything down (usually, to right under the rear main). Cleaning up the engine helps a lot in that case.

UV dye is really good for small, slow leaks. But with a big leak, you can end up with the same problem; fluorescent oil everywhere!

 

I have located the leak, its coming from between the head and the block. What I haven't figured out is why. Gasket bad enough to allow oil to leak from the oil port in the block maybe?

 

Sure. The head gasket seals water passages, the cylinder space, and oil passages. Which one fails first? The only reasonable repair is to replace the head gasket. And soon.

 

I have the same issue.
any updates?

 

Whoever put the head gaskets in before over torqued the head bolts. Caused the gasket to stretch and allow oil to flow out of an oil passage. As much as I hate to tell you this, it's time to do head gaskets.

 

I have the same problem. and I dont believe you can over torque a head gasket. you can over torq a head bolt but not the HG... too much to cause an oil leak. what ever is leaking is not under combustion compression. I changed mine about 3 years ago with new bolts and torq correctly. my guess is that the gasket needs that small o-ring for the oil passage. Can anyone confirm what is on this corner of the block? is the oil pressure going up to the cam in this corner or is it the drain? I cant tell yet but its seems to be only when running and not just draining. I dont recall but Im going to guess it was a Fel-pro HD set.

 

I'll add my head gasket horror story. 1995 4-runner.

Thursday nite, driving home engine started to stumble intermittently, when I pulled in the driveway, LH side blew, engine stumbled and beautiful cloud of white smoke from the tailpipe. Shut it down and saw coolant running from the area of #6 - pulled spark plug and ya, coolant in cylinder. What luck, right when I got home so no towing bill!
Ordered gasket set from amazon, got it Friday and set to work - Sunday night get it all back together, crank it up Sunday evening and had an OIL WATERALL from the back of the engine. Huge mess.

The only place there is oil pressure back there is the HG. Looking at the old gasket there is a small hole I assume is for oil supply right on the back of the RH gasket and I bet that is where I screwed it up. Sooooo looks like I have to re-do the thing. MAJOR PITA.

I think I got kinda clumsy dropping the heads on there and damaged the gasket. Going to be extra careful on the do-over (not a fun job!) and make sure I baby the damn gaskets this time. Pretty sure I abused the LH too so may as well hit both.
I have some wooden shims that are used to install doors and windows, going to use 'em to protect the gasket while I drop the heads in and jockey them into position - then slide the shims out and ease the head down onto the dowels. Trying to do this over a 2 day weekend got me in a rush and I screwed up for sure.

Oh, and I hate that damn crossover pipe but should be easier this time since it has not been heated and I liberally treated the nuts with anti-sieze. But I still hate it LOL.