wyoming85

I purchased my '85 a couple of months ago, and I took the engine out to replace crankshaft (the key was loose), timing chain kit, gasket kit, distributor, and other few things. After putting all things together as a complete motor, I put it back in and ran for around 500 miles under 60 mph to break-in. It ran really great, no oil leaks, or anything at all. HOWEVER it burned around 3 qt of oil on around 1.3k miles trip. before during re-assembling the motor , my friend and I checked the pistons and the rings were in good shape, didn't fall out of the cylinders when the crankshaft were replaced.

Is it valve guides problem? what do you think?

flatyota

Was this a full rebuild (pistons rings ect) if so during a break in the engine is suposed to be broken in in a little bit different way. I have read on varies sites that to seat rings propperly the engine needs to experiance different levels of loads and also see cool down periods. I read that you are suposed to run one drive hitting low rpm's and a lot of throttle to load the engine without wrapping it out. Then let it cool down and drive it again this time getting into the higher rpm range letting it cool down again after and then continuing this for a while. Also I heard that if you use synthetic oil on a breakin the rings almost never seat propperly. Im not saying you wrong but maybe this could be some of your problem or could maybe help ya. not having well seated rings can cause alot of oil consumption.

wyoming85

During the rebuilding process, my friend and I checked the pistons and smoothness of cylinders. Rings, pistons and the cylinders were in good shape and didn't fall out when the motor was down turned. Seemed to us that rings were snugged tightly well, not loose. Some people said that it might be valve guides problem, some people people said it is pistons problem. I don't really want to go back all over again to pistons, I am going to try check on valve guides, but I don't know where to start. I am new to this again.

Thanks

84toyota4x4extcab

deffinetly the valves i had the same problem with mine

Jager

Well, just because the pistons didnt fall out and the cylinders were smooth doesnt nessesary mean that they are fine. Without measuring the cylinders its hard to tell. The other thing you could do is a compression test to see if the cylinders are in spec and then add a little oil to the spark plug hole to see the if the comp comes up. All that being said when your breaking your engine in for the first time, I think their suppose to burn a little oil? Maybe not that much though. I really need to rebuild my engine, it burns oil like a refinery!