For running in a new cam and followers. About to build the engine back up but need advice on ‘running in’ pastes for the new cam and followers please. Also, been advised in the rebuild to cover everything in a high zinc oil then fill with the same oil for its first ‘burn’. Then drop the oil for what I would normally use. Break in for 500 miles with no overloading the revs. Then reset valve gaps and drive as normal. Any recommendations or advice, helpful. Thanks in advance.
not sure "cam paste" is necessary. High zinc and phosphors oil is like Penrite and mobile 1 (which the cam paste may have, check the label). start and run your engine run it at 2000rpm for 30 minutes, job done don't red line it for a while (it's about work hardening the rubbing surface's between the cam and lifters)
I've done two, neither times did I use any cam paste. I coated everything in oil as I went (high zinc as noted), then cranked with plugs out until the oil light went off to prime pump etc before cam break in (neighbors loved that, surprising how annoying an old aircooled engine is at 200rpm for half hour!). Didn't have any issues with either. In terms of running in, I was told that whilst you shouldn't make the engine labour, or hit really high revs you do need to give it some load to help the rings bed in. Under load the rings press out into the barrels to seat, then as you ease off apparently it helps suck a little bit of oil back into the rings to cool/lube. Mahle have a guide: https://www.us.mahle.com/media/usa/motorsports/mms-break-in-recommended-procedure-web.pdf Apparently just driving everywhere like a nun is likely to give you glazed barrels and poorly seating rings.
Cam lube protects the cam during the time it takes for the oil to spray onto the lobes. There are many to choose from, this is one https://www.race-store.co.uk/product/penrite-cam-assembly-lube Use running in oil for the first 500 miles, then refill with whatever you normally use – assuming it’s the correct grade of course.
OK 77Westy, its been over 31 minutes since your post and everyone has resisted temptation so here goes ..... What's the correct grade oil to put in the engine of my bus ?
I used 3 in 1 oil because it was in a convenient container, and the engine was fired up pretty soon after assembly with the usual cheap Green Tin Gloop oil level a bit over max . I couldnt be bothered to wait for any delivery of assembly lube, as it would have slowed the build down. . Not ideal, but the engine ran for many miles before dropping a valve..
It was a stainless steel valve, by the time it failed it had done 50k miles on a " good" head that was reused from a previous engine. It blew as I came to the top of a 3 mile gentle hill. That day I wasn't driving it totally pedal to the metal, the carburettor does tend to run leaner as you back off. That's all I know. The engine ran for 30k miles from rebuild to failure.
I’ve just used this stuff.. https://www.moss-europe.co.uk/cam-lube-ken2.html Seems fine, will let you know if it’s anyone good in 50,000 miles time! (Went into local motor factors first and asked for cam lube and got the you-must-be-from-another-planet response.)
About ten years ago I popped into the local motor factors and asked for a timing light The guy behind the counter didn’t have a clue about what I was asking for.