I want to thank everyone for the support on my last couple of posts. I ordered a couple things from thunder racing yesterday and Gene from thunder racing called me to let me know that the t-shirts I ordered with the parts were backordered. He asked me what I was building up and recommended running diesal oil in the card and let it cycle for like 20 minutes, drain and put my synthetic in. I could see diesal being good for maybe the gaskets but I havent heard about using diesal oil for a build....Any thoughts on this subject?

 

Did you recently do a complete rebuild? WTF?


PMed.

 

It's just 15w-40 right? Never figured why they call that weight Diesal oil.

 

The 15w40 oil that is ran in diesel oil is a higher grade of oil then any of the newer oils with the starburst eblem on the bottle. They contain higher levels of zinc and other addatives to reduce piston scuffing and reduce wear. I beleave the rating you would want is CI-4. The instructions I got with my T&D shaft rockers said do not run with any oil that has a starburst rating. API guidelines

 

Because that weight is only recomended for use in deisels it is (like Jake said) formulated for deisel engines.
40 weight designed for gas engines is 10w-40.

As far as using it for startup on a complete rebuild, maybe. But for a simple heads/cam swap it's not necessary at all.

 

Aren't the higher levels of Zinc, Phosphorus and other elements in some diesel lubes death to catalytic converters? Especially in a new build since the rings would not be completely seated yet.

 

It's just a bad idea altogether...

You can use regular oil, straight weight or multi-weight to break in a NEW set of rings....change the oil at 100 miles, 500 miles, and 1500 miles, and then you can switch to a synthetic.

Some people like using a high detergent oil for the first 100 miles after they completely build a motor due to the high amount of assembly lube and bearing material swishing around inside -- I don't think that it's necessary.

HOWEVER:
In this case, this guy is simply swapping parts, so a full break-in procedure isn't needed. The only thing that I'd do is change the oil if assembly lube is used on the camshaft and take it easy on the new camshaft for the first 50 or so miles and put it through a few heat cycles.

Sounds like he was given some odd advice.

 

Yup, I wouldn't do that at all.

 

its only needed if you are breaking in a flat tappet cam.... its not going to help a roller engine very much

and who uses a detergent oil for break in ??? ....i have always been told straight weight oil with no additives