C-263 valves

Fritz Maurer · Apr 26, 2013

This subject comes up every now and then, and the cure is well known, but what exactly causes the valve to burn from using the wrong oil? What is different about these valves compared to any other? Why is this problem only in this engine, or family?

L Hud · Apr 26, 2013

I think it is because these engines run lean when they are worked. A machinist told me this when he first looked at my head. The engine was running too lean. I put sodium exhaust valves and stalite seats in the head. I have not had any trouble with the valves since. Hope this helps. Hud

Janicholson · Apr 26, 2013

Ash in oil is composed of non-combustible additives and metals that are present in oils (even the newer diesel oils do not meet the IH spec of .5% ash.
The non combustible materials fuse to the valve stem. and create a buildup that can and does migrate into the tip of the guide just as the valve closes, thus allowing the valve to get hung up and a tiny bit open. This prevents cooling, and allows the valve to get so hot that it changes shape and fails as exhaust screams past under combustion pressure. It is like cokeing, but is more like ceramic, and less like a briquette, Jim

teddy52food · Apr 27, 2013

Jim is right. I knew this but it is hard for me to put it in words. Local guy here had a 706 that when working hard at night would throw a shower of sparks out the exaust. Another valve job needed. Back then we didn't know about the ashless oil usage.

C-263 valves

Fritz Maurer

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L Hud

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Janicholson

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teddy52food

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