Subject: Re: [Amc-list] Engine Break in - Synthetic Oil From: Matt Haas <mhaas@xxxxxxx> Date: Wed, 08 Aug 2007 20:03:42 -0400 To: "AMC/Rambler owners, drivers and fans." <amc-list@xxxxxxxxxxxx> During break in, there are two main parts that need time to seat. The first is the camshaft (running the engine about 1500 RPM for 20 minutes does that and the reason for the higher RPM is to make sure the lifters rotate) and the piston rings. The card that came with the piston rings in the engine for my 68 American (they are Sealed Power rings -- hardly anything exotic) said that if the cylinders are finished a certain way, the rings will seat in the first 10-15 minutes of run time. If they don't, you have to refinish the cylinders and replace the rings. I know that Mobil One has said that you can use it's oil for break in and it will not interfere with the process but as was previously pointed out, it doesn't make sense economically. Matt ===.=== 1500 for 20 minutes: Yes - this is for an engine that was assembled with crosshatched and oiled cylinder walls - for storage / shipment reasons - rather than dry freshly crosshatched cylinder walls. 'A certain Way' : said that if the cylinders are finished a certain way, the rings will seat in the first 10-15 minutes of run time. : Yes - freshly crosshatched - straight bores - no gouges or scratches in the cylinders. Back when, many new Porsche engines wouldn't seat rings correctly - they were oiling the cylinder walls and dipping the assembled pistons in oil before installing them into the bores. Chrome rings were the rage - pretty hard stuff - which required a medium crosshatch to cut themselves in. One other note: Early Synthetic oils didn't stay on parts very well - but did slick thing up enough to defeat a 'break in' in anything less than a 'dry' break in. -- ___ =Bt= /~ ~\ milnersXcoupe |_ | "The Heretic" |/ __-__ \ /~ ~~-_ ~~ -~~\ ~\ / | \ , / / \ // _ _---~~~ //-_ \ / (/~~ ) _____/-__ ~-_ _-\ _________ / _-~\\0) ~~~~ ~~-_ \__--~~ `\ ___---~~~ /' /_-~ _-/' )~/ /' (___________/ _-~/' _-~~/ _-~ _ ----- _~-_\\\\ _-~ /' __--~ (_ ______---~~~--_ _-~ ~-_~\\\\ ( ( -_~ ~-_ | ~-_ /~~~~\ \ \~~ ~-_ ~-_ ~\ ~~--__-----_ \ ; / \ ______-----\ ~-__~-~~~~~~--_ ~~--_ \ . | | \((*)~~~~~~~~~~| __--~~ ~-_ ) | | | \ |~|~---------)__--~~ \_____________/ / , \ ~-----~ / /~ ) \ ~-----~ / ~-_ _-~ /_______________________________/ `-_ _-~ ~ ----- ~ ~ ----- ~ -------------- next part -------------- An HTML attachment was scrubbed... URL: http://www.amc-list.com/pipermail/amc-list/attachments/20070809/b9dae65f/attachment.htm _______________________________________________ Amc-list mailing list Amc-list@xxxxxxxxxxxx http://www.amc-list.com/mailman/listinfo/amc-list