I am getting a little smoke when I start up after it has been sitting. With 141k k on the odometer, my guess is it is time to rebuild the heads. What are your thoughts, pull them and hand them over to a machine shop, try to rebuild them in place. Have any of you guys had any experiences with them and what should I be budgeting for this?
Time for valve seats?
- Thread starter Kaibab
- Start date
Outdooraholic
Adventurer
I haven't done the valve stem seals on my Montero Sport yet, but I have done them on both my Mitsubishi Eclipse and Evolution. The Eclipse I did with the head on the block and used paracord in the cylinders to keep the valves from falling in. It was tedious but worked pretty well, with the exception of dropping my very last keeper down an oil passage and having to pull the pan to get it back. On the Evo I pulled the head and changed them on the bench. (On both cars I was also installing upgraded camshafts at the same time). Doing it on the bench was obviously much easier. And this was on an inline 4 cylinder that is much easier to work on then the v6 in the Montero's. Personally when I go to do mine on the Montero Sport, I will probably pull the heads off, change the seals on the bench, and then reinstall with new head gaskets. My Montero Sport is going to need them before long as well. I just wish I had known back when I first got it and tore into it to change the leaking cam seals and did a full timing belt job. It would have been easy then.
As outdoor mentioned, its not the seats, but the valves seals that are failing which is allowing oil into the cylinders. This is a known and common issue with this engine. There are a few write ups on Expo on how to replace valve seals using the "rope method" with the heads in place. In particular look for the post by Jay Ayala.