Can not figure out where this fricken leak is coming from

So.... despite everyone telling me dont do it, I bought a $1000 1991 4x4 3vz 4runner.... with a severe oil leak. I gladly bought it and towed it to my buddys place.

This leak is multiple drips a second off of the lower timing cover. So we pulled the oil pump and redid the main seal, the o ring and put it back together with sealant in all the right places. Put the timing shiz back on and found that it still leaked (thank god we weren't confident enough to put the front diff back in).

So we took the timing covers off, wiped it down and started it up (with out in the fan). We looked around and are thoroughly convinced that the main seal is leaking. Oil doesnt seem to be coming down from anywhere up top and I could see oil collecting on the lip right below the crank. I do see oil midway up the block and but not nearly enough to contribute to the quantity collecting at the bottom. I think it is getting slung up from the bottom pulley.

The car has 225k miles. We used a national 224020 seal if that makes any difference and basically no difference when we put the new main seal on.

We can only figure the main got screwed up on installation (unlikely imo, seal was in pump housing when the pump housing was installed), or the crank is worn.... which means 22RE swap.

What other things can we check before dropping the oil pan again?

 

Did you check for or notice a groove on the crank journal where the seal lip rides? If there is one, the seal has a mighty difficult time actually sealing. You may be able to "cheat" by installing the seal either a little deeper or not all the way "home" so the lip rides on a new surface.

 

If there is a groove on the crank journal as suggested, a better solution might be to install a Speedi-Sleeve

 

I'm not sure about 3vz oem front seals, but I know Toyota has an updated 22r/re front seal that relocates the seal lip so it does not ride in a groove where the original seal was. You can look into that, or use a speedi-sleeve, or install the seal in a different position like mentioned above.

 

I agree, however the OP did not seem interested in that "intensive" of a solution.

 

Hi:
On the 3VZE motor the rear cam seals are notorious for leaking.
The oil will leak out, and run down the back of the motor, and make a god awful mess. You will say OMG the rear main seal is bad.
A clue is, after a reasonably long run you will have a hot oil smell from the oil dripping on the exhaust crossover pipe when you shut the engine down.
You won't get this smell as much, or at all, from a rear main leak because the crank main seal is below the crossover pipe.
After a while you won't be able to tell where the source is unless you power wash the motor and start over.
The valve covers are the second worst offenders. They are made of some kind of mystery meat that warps and hardens with age and heat cycles.
A red neck fix I have used is to lightly roughen both surfaces (cover flange, and cylinder head lip), with a die grinder, to provide gripping surfaces, and then use only "The Right Stuff" , sparingly, no gasket needed.
It works like a charm.
The cam seals won't be as easy. They will take all day Saturday, stopping for lunch and a beer.
You must change both of them because if only one is leaking, you will change the wrong one. Don't ask me how I know this.
Good Luck.
Art.

 

So... this is embarassing... It was a main seal. i feeled around on it and found that is was put on wrong. got a new one on and the thing hasn't leaked a drop since.

 

Good that it is resolved. No recriminations from this corner!