PhilR

I recently replaced the head gaskets on my 3VZE because it was slowly drinking coolant. The oil wasn't bad but the oil cap had started to show some light brown creamy deposit. When I replaced the head gaskets, I found that they were not like new but probably not bad enough to leak. I had the heads pressure-tested and resurfaced. Now that everything is reassembled, it has the exact same slow leak, which I think is internal. The oil cap still shows the same light brown deposit and the coolant level in the overflow bottle still drops. I added dye in the coolant and I haven't seen any traces of external leaks.

I'd rather not go through this process again to get the kind of result I got, the engine has over 203,000 miles and I had been searching for a good lower-mileage replacement engine for a few months before I did the HG job but I didn't find one. While I was aware of the problem and looking for another engine, the problem didn't get worse but I did drive it 3000 miles knowing this condition. Since I replaced the head gaskets early in May, I have driven it for another 2000 miles and the problem hasn't changed. It drinks coolant at the exact same rate as before...

I had the oil cooler checked for leaks in a radiator shop and it didn't leak. I feel like I'll have to look for another replacement engine again but first, is there anything else to check which could cause coolant to get in the engine oil? I'm not 100% sure it's leaking in the motor but I drive it on long distances and I'd be very surprised if the deposit in the oil cap is caused by condensation (I drove it for over 75,000 miles in the 6 years I had it and it has never done that before).

atthegates78

When you had the head off you said you had it resurfaced. Did you do anything to the block?

PhilR

No I just cleaned it and checked to see if it was straight with a small set square while the block was removed from the truck (I also changed the oil pan gasket and the clutch/flywheel as well as the transmission's front seal at the same time.
I didn't spend an hour checking that and I'm not used doing this but everything seemed OK to me.

Yesterday, I drove over 500 miles with it and the coolant level dropped about an inch in the overflow tank after the engine cooled down. The radiator is still full and curiously, the light brown creamy deposit under the oil filler cap is almost all gone. I'm guessing it will be back when I drive shorter distances.