When Tim Speaks, You Should Listen.

My 1992 Previa has a bad head. I had the head gasket done 16 months ago and they had it was discovered that their was a hairline crack in it. The mechanic told me that it could be welded and the van would be fine. I had discussed this with Timsrv and he told he was very weary of this. I decided to let the mechanic do his job since he told me that he too had over 200,000 on his Prev with a welded head. Not taking heed to Tim's thoughts on it (again) has turned out disastrous. Sadly, mine didn't even make 40,000 miles before it started overheating. My new mechanic told me that it was the head and it looked like the head had been taken off before plus it looked like a "Mickey Mouse" job. This time, he wanted to replace the head but with 192K on the odometer, I decided to go with a used JDM engine. Prices have gone up in the last year so now the engine is costing me $625 instead of $400. Now I have to put off buying an All Trac this year because of this. Tim, from now on, I will take your advice 100%. You seem to be the only one who really knows these vans.

Lol, my inflated ego is going to make me impossible to be around for the next few days (my wife is going to hate you). I am however sorry to hear about your misfortune. I was hoping I was wrong, but as you now know, that seldom happens :wnk:. For anybody interested, the original discussion that terbennett references is over on TVP. Here's a link: http://www.toyotavanpeople.com/forum...hp?f=11&t=6996

The head on my 94 all trac cracked down the #3 spark plug thread hole and they went deep. Welding on this would only have been surface if it even held up there. the coolant runs internal and so any cracks deeper would have coolant go through them. Not to mention my spark plug hole would need a re-tap.

I just pulled one from the junk yard and still going strong. Only a couple thousand on it now.

The reason coolant did not show up in oil, which turns the oil to brown sticky baby poop and it can do it immediately with brand new oil. is because the crack let coolant only go into exhaust combustion chamber and hence the white smoke. a bad head that does not show the smoke is only getting coolant in your now brown oil.

I did a test one time and mixed coolant with oil in a glass jar, and it did not turn brown. I'm guessing the brown comes from heating the two together. I did see clear condensation inside the oil fill hole and under the cap after running at idle 5 minutes and this was enough to turn new oil brown but when drained could not see coolant just a general brown dull color.

I got the Prev back Friday with the newer engine. It runs great- better than I remember my Previa running in years. My mechanic even replaced my engine and transmission mounts. Only issue is the overflow valve was releasing a lot of coolant initially. I checked the level later after another drive and it was fine. Yesterday the overflow valve once again started releasing fluid but this time it was water and brown stuff. I'm thinking it's the water that I had added to the cooling system when I was on my way to the mechanic but it makes me wonder why the shop didn't flush my cooling system before giving me back the car. I will do it myself today to make sure it's done right, but I can't help but wonder if there was something else they didn't do. Maybe I'm being too picky, but that seemed like an obvious thing to do with an engine swap. If I ever have this problem with one of the other three Previas (I love saying that), I will do the swap myself.