legacycentral bbs

I have done engine rebuilds on other makes of cars before and agree the prelubing is a necessary thing if you want the engine to live. I have thought about how that might be done and am thinking that spinning the engine with the starter with no fuel supplied and no spark plugs in place would accomplish the needed prelubing...the question is how long do you crank the engine over and how do you tell for sure that you have achieved the desired lubing? guess I could screw in a mechanical oil pressure gauge where the oil pressure sending unit is and see when I have oil pressure. Any thoughts?

You can just disconnect the crank sensor. The oil light will turn off when it's primed.

With spark plugs out it works better but you can leave them in.

I did this when I rebuilt my motor and I disconnected spark & fuel. With the spark plugs out it's easier on the starter motor. I cranked until the oil light went out.

The only downside to this is the hydraulic lifters. If you bleed them prior to rebuild they should be good, but as you roll the engine there's a chance they could collapse a little bit considering you don't have any oil pressure there yet. I think the last time I rebuilt the motor I pre-lubed and then pulled the valve covers and rockers off to bleed/check the lifters again. I know it was kind of a pain in the ass, but I didn't have nearly the lifter noise I had after a previous rebuild.

You could just wait and see how it goes after first start up. They should pump up and be ok, but I personally didn't feel like doing all that work and then not doing this final one thing.

good information guys, once again you guys rock

also, taking the plugs out does reduce the possibility of damage to the bearings, just thought of that

WRXish wrote:also, taking the plugs out does reduce the possibility of damage to the bearings, just thought of that

That is a good point.