[Skutt]

I have a 2000 Sienna with 130,000 miles on it. Because of the engine sludging up it eventually lost oil pressure. I wasn't aware of the sludge problem with the engine until it was too late. I shut it down before it did major damage but a couple days later my wifes oldest son came to the house while I was at work and asked to listen to the engine run so my wife gave him the key and he started it. Of course the engine sounded fine because I had shut it off when it happened and had the van towed home. The engine was still undamaged until he drove it around the block to check it out without oil pressure. :headbang: Besides wanting to decapitate him I have fixed the damaged bearings by having the crank ground .0010 and putting in oversized bearings. Now I am nearly ready to put the engine back in the van but I wanted to check the compression just to make sure all was right before going to the trouble of installing it and then finding out I might still have troubles that would be easier to fix with the engine out on the garage floor bolted to the front suspension member. I just did a compression test. I put a new timing belt on and it is correct. The cam timing is right on the mark. I put oil in the engine and a new filter and cranked it over with all the spark plugs removed. Only one cylinder has good compression, the rest are very low, around 30 pounds. I am thinking that since there was no damage to the timing belt, which was nearly new when this whole thing started and I removed the camshafts and inspected them, cleaned them, lubricated the lobes and bearings with lithium grease when I put it all back together I must have valves sticking. This has been a long time project and my wife really want's her van back on the road as do I.

I am thinking of removing the valve covers and cams again. Pouring a good penetration type oil down around the valve stems and let it set for a few days to see if that makes a difference. Any other suggestions from the engine experts here? If I have to replace the heads then I am junking this engine rather than put more money into it.

 

[Skutt]

I see there have been a lot of views of my post but no replies. Well this is what I have done in the past few hours since I first posted. Each time I crank the engine enough to get an accurate compression reading the starter motor gets hot real fast so I stop for awhile. If anyone has searched for a new starter you know they are a bit spendy so I am trying not to burn it out. Now, though, after cranking the engine enough to get oil pumped throughout all moving parts I am getting better compression readings. Not what they should be yet but better than when I first started checking. I will simply keep doing what I have been doing all afternoon and hope for the best. A good amount of fresh oil on the valve seals just might do the trick. I let the engine sit for awhile and allow the starter motor to cool off and allow the oil to sit around the valve seals. So far it has made a difference but time will tell if this motor is really worth the time and money I have put into it so far.