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MG MGA - First oil fill

Not that I am quite there yet, but when I fill my reassembled motor for the first time, how do I prevent the oil from washing off my cam assembly lube, as it flows down the pushrod holes?
Art Pearse

Greetigns Art,

While attending one of the many worskshop at last year's NAMGAR in West Virginia, I was lucky enough to hear a guest speaker who discussed engine rebuilding and the very important, initail start-up process. He STRONGLY suggested that "Mr. Moly" oil additive be included in the process. This gives the extra protection required and helps all the surfaces mate correctly. Spin the engine with the sparks plugs removed long enough to circulate the oils thoughout the engine. Replace the plugs. Once you get the engine started, you should run it non-stop at 3000 RPM for at least 15 minutes. He also recommends Rotella motor oil as a regular lubricant as it has a very high zinc content. Hope this helps. Cheers!
Robert Maupin

OK Robert. I have used moly cam lube from a Crane, 50/50 with lithium grease. But I have answered my own question - there are separate drain holes so the oil fill does not flow directly onto the cam.
Shell Rotella 10W/40 has also been recommended by my machinist and thats what I'll use.
Art Pearse


Mr. Moly is an oil additive that should be included in your initial oil fill before you fire your engine up.
Robert Maupin


Unless I am reading mr moly wrong, it's one of those additives that clings to cylinder walls etc to prevent wear. Surely during the initial engine break-in period you need the wear to seal the gaps between piston rings and the cylinder wall etc. I would have expected you to say to add My Moly after the first oil change.

Steve Gyles

Greetings Steve,

I understand your logic but on the container it actually states, "Mr. Moly Break-in". I qoute:

Even with the most extensive machining and honing, surfaces appear rough and jagged when viewed through a microscope. As these rough surfaces rub against each other, they can weld together and then shear apart creating tremendous friction and heat. This is why new or rebuilt engines run hot until they are broken in. Metal surfaces become scuffed or scored.
Mr. Moly Break-in helps eliminate scuffing and scoring and promotes the flowing out of metal high points. Highpoints are flattened, not broken away. As a result, increased performance and protection during the critical initial running of a new or rebuilt engine. This also promotes better engine performance throughout its life."

It also states that its good to run Mr. Moly after break-in period as a continued additive.

As I stated earlier, this product was unknown to me until I attended the workshop at the MGA National. The speaker who led the session is an expert on the subject. Use one can of Mr. Moly Break-in for each 2-4 quaters of oil. Cheers!
Robert Maupin

This thread was discussed between 28/05/2009 and 29/05/2009

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