engine assembly

[67rcks]

I am wondering what it is best to use for engine lubrication during assembly. Will regular oil work or some special lube is recommended or required?

 

[LMan]

I use STP. ...old school.. :Word:

 

[Decurion]

Engine oil for the cylinders/pistons is fine, but I like Torco MPZ assembly lube for the crank (rod and mains) and cam and valvetrain.

 

[wicked93gs]

I've always used engine assembly lube for the rod/main bearings, engine oil for the bores and pretty much everything else

 

[D.Hearne]

STP oil treatment for the bearings, motor oil in the bores and rings.

 

[rbohm]

while i have used white grease in the past, i dont recommend that. stp or a good assembly lube is the way to go. remember that if you are using a flat tappet cam to use a proper cam lube on the lobes anb dist gear.

 

[67rcks]

Is a moly-based grease good for bearings? I am asking as it is quite difficult to rotate the engine by hand (holding front dampener, freshly bored&honed, new rings, no heads). And I used black moly grease for bearings (only the friction side). Became much harder after installing conn rods with pistons. Now looking for possible reasons before taking everything apart. By the way is a new engine supposed to rotate easily? Crank and conn rods should be OK; at least old bearings don't have any unusual wear.

 

[D.Hearne]

We used Moly grease on the bearings once and had the same results. Part of it was the main caps being mixed up (#'s 1, 2 & 4 weren't numbered correctly at the factory) Part was the moly grease. This motor had other problems and after disassembly after 50 miles, still had moly in the bearings and oiling passages. Bottom line---in addition to the moly there, did you make certain the rod and main caps were installed correctly? And the rods facing the way they need to be?

 

[oz]

Mix STP with motor oil. It is super slick but will stick to the parts until you start up the engine.
As said by others, use proper assembly lube on the cam lobes though.

 

[67rcks]

We used Moly grease on the bearings once and had the same results. Part of it was the main caps being mixed up (#'s 1, 2 & 4 weren't numbered correctly at the factory) Part was the moly grease. This motor had other problems and after disassembly after 50 miles, still had moly in the bearings and oiling passages. Bottom line---in addition to the moly there, did you make certain the rod and main caps were installed correctly? And the rods facing the way they need to be?

I am sure everything is installed correctly including rods, rings with .010+ gaps and main caps in correct order. Rods torqued to 25 ft.lbs, and mains to 65 ft.lbs. What can cause a problem are somewhat coarse cylinder walls, bearing vs journal clearance (at least crank w/o pistons rotates easily). The guy who grinded -.020" off the crank journals sweared he measured the clearance with micrometer. Some pistons's wrist pins are also installed rather tight in the pistons (become easily spinning at some 50 celsius). I am curious if such resistance is rather normal for a rebuilt engine?

 

[D.Hearne]

You will get a lot of resistence after installing the pistons and rings. If the crank rotated freely before this and the correct undersize bearings were used ( should be .001-.003. bearing clearance ) you should be good to go on this. The piston pins should also have clearance in the pistons at room temps (you're not doing all this in a freezer I assume?) And should rock and slide freely on the rods.