Leaking Toyota 1MZ-FE

[FL-400S]

Toyota 1MZ-FE ~122k miles. Had valve cover gaskets changed, still slow leak. Indy mechanic says bc of shoddy gasket job by dealer when timing belt done at 85k. Anyhow, its full of Peak 5w30 conventional right now, topped off with a quart of 5w20 pennzoil synthetic I Think, due to dripping and maybe burning some. I have 5w30 and 10w30 QSUD, and some carquest synthetic 5w30 in the garage, as well as my standby FL-400s filters for it. ITs got about 2300mi on the OCI currently.

Id rather not go buy high mileage oil if not necessary right now. Also, I try to keep syn in this engine due to chance of sludge. OR run a shorter OCI if conventional.


To minimize the leak, should I try the 10w30 at next oil change? Is there anything I could add to maybe help the leak?
Thanks!

 

[Nick1994]

Do you know where's it's leaking? Oil pump seal, oil pan gasket etc.

Changing the rear valve cover gasket on a 1MZ-FE is an extreme pain. The entire intake manifold has to come off.

 

[landtoy80]

Could be the crank seal leaking behind the harmonic balancer?

If its a bad valve cover seal job nothing will fix the leak other then replacing the gasket.

There is a common problem with the 1MZ-FE valve cover bolts bottoming out and not putting enough pressure on the valve cover gasket. I have personal experience doing this years ago.
I had to add two washers to the bolt to shim out the bolts. Doing this, the gasket may seal better. You can do a search for the washer mod. I think it might be on Toyota Nation. Same can be done by installing shorter bolts.

You can check the valve cover your self. Try and tighten down a few of the bolts on valve cover. IF they turn, then re-torque them. On my Camry it was 69 in/lbs. If the bolts don't trun (bottomed out) then you stick some washers on the bolts to put more pressure in the valve cover/gasket.

 

[FL-400S]

I took it back to the indy mechanic when it was still dripping after the valve cover gaskets were done, and he said it was leaking from behind the timing belt cover, probably the result of a shoddy job during timing belt replacement. It's not something I'm going to fix myself. It will probably have to wait until the next timing belt change, if I keep it that long.

 

[landtoy80]

I remember trying to tighten some of the bolts, I removed the t-belt cover and some of the bolts were loose on mine. Its a tight fit but you can reach some of the bolts/screws.

You could try and use

if you really worry about it. I had used the stuff before. IF you can loosen the bolts some and spray the Spray Sealant where it is leaking (after cleaning up the area with some spray solvent cleaner)then tighten it down, it might slow the leak. IF you can't loosen the bolts, just clean it up good and spray it on. It worked with my Camry when I had leak there.

 

[kschachn]

Originally Posted By: FL-400S
I took it back to the indy mechanic when it was still dripping after the valve cover gaskets were done, and he said it was leaking from behind the timing belt cover, probably the result of a shoddy job during timing belt replacement. It's not something I'm going to fix myself. It will probably have to wait until the next timing belt change, if I keep it that long.


If it is leaking "from behind the timing belt cover" then it is coming from one of the camshaft seals, the crankshaft seal or from the edge of the valve cover. That's the only places where there is an interface with oil. A "shoddy job" of timing belt replacement would have meant that these items were not replaced and should have been.

Or you have a massive head gasket leak but that's not associated with the timing belt either.