I’m in the middle of some major engine work on my wife’s Toyota 1999 RAV4 (2WD, California emissions). The major motivation for this is the clutch and a head job. I’ve now got everything taken apart, and I cannot decide on whether or not to work on the “bottom end” (i.e. the short block). Here are the details:
- The vehicle engine has 175,000 miles on it. We’re the original owners and it has been generally well maintained. No overheating, etc.
- Over the past couple of years, it had gotten to the point of burning about 1 quart of oil about every 800 to 1,000 miles.
- The burning oil seemed only to be coming at startup, thus strongly indicating bad valve guides and/or seals.
- Sure enough, after getting the engine apart, it is clear the head needs to be done, and the exhaust valves in particular have been leaking oil.
- A compression check before taking everything apart had each cylinder at 140 to 145 psi, with no meaningful increase doing the check after a squirt of oil into the cylinders. Spec for this engine is 128 min, 178 max.
- There’s a lot of carbon build-up on the tops of the pistons, but I think that is clearly from age and the leaking valve seals.
- The cylinder bores all seem pristine. No burn marks, gashes, scratches, etc. In fact, the original honing cross hatching is still clear.
- Oil pressure seems fine.
SO … here’s my dilemma. I’d like to not have to deal with the time and expense of redoing the block, and given the strong compression and good visual inspection, it seems like the block is probably fine. However, am I just being a fool in not re-ringing and replacing the crank and rod bearings while I have the engine this tore down? I’d be happy if I can get another 50k or more out of this block as is. Is it normal for a Toyota 3S-FE block to still be strong well past 200k miles?