my engine is all original. probably un opened from 1967 and i have the gaskets to prove it.

question is i just changed my oil iwht a synthetic blend. normally i like to run synthetic in my cars and change the oil at the same interval as a non synthetic car.

if i switch over to a full synthetic on my car will the oil find its way through the old gaskets. i will eventually replace all of them but that might not happen by the next oil changed which i have planned for in a month or two.

 

Yes, it likely will. Only one way to find out, though

 

The problem was the old synthetics. The new synthetics will not cause a problem. Use a diesel grade for the zinc.

 

i run Torque Q in my old mustang and my jeep

i find that my jeep which see a lot of high rev low gear off roading abuse runs smoother and cooler with the Torque Q.

saying that, is the zinc that important? never heard of it before.

 

sorry not to hijack but i always thought you weren't suppose to switch from conventional to synthetic? so to be clear can you switch to synthetic without repercussions?

 

It has nothing to do with new or old synthetics, it has to do with the fact that synthetic oil(no matter theage)flows so well that it cleans out all of the gunked up deposits in the engine, including those in the old cork gaskets that are preventing oil from leaking out. New gaskets generally fix the problem.

Yes, zinc is very important for older flat-tappet cam engines. It's an important anti-wear additive that ismostly removed frommostoils. I recommend using Valvoline VR-1 for a non-synthetic as it's designed specifically for flat-tappet race motors. High end synthetics like Red Line and Royal Purple also have a lot of Zinc. Some diesel oil still has a high zinc content, but that won't last long since '07+ diesel vehicles all have cats now. Castrol's Delo has been switched over to the new CJ-4 low-emissions rating for months now.

 

i like the royal purple too. is this a good choice?


dugan, you have to flush out your engine good first with an engine cleanser.

well thats what i do. my jeep has 120k on it and weve ran synthetic since the end of the warranty. which was at 60 i think. i beat the sh** out of the jeep. surprised its still in awesome shape.

but you know each engine is different.

 

Eastwood makes a Zinc additive. I do not have any experience with it but it sounds like the material we need for our flat-tappets.

I am still unclear if the Zinc is needed just for break-ins or at every oil change? Any insight on this anyone?

(did not mean to hijack the thread)

 

be my guest i hi jack everyone else.

i use a off the shelf engine flush when ever i do an oil change. like Restore.

and i always add some seafoam periodically.

but thats different than zinc.

 

Zinc isabsolutely vitalduring break-in, but it's not a bad idea to run a high-zinc-content oil (or oil with an an additive) for the life of the engine. It acts as an anti-scuffbarrier in the case that you ever get metal to metal contact. Cam lobes like it