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leakdown/compression specs history

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leakdown/compression specs history


Old 02-07-2007, 01:53 PM
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Default Re: leakdown/compression specs history

On a 4 stroke, it should be done at TDC compression stroke so both valves are closed. It's a time consuming process.

When I do a leak down test, I pull the valve covers and pull the rockers so all valves are closed.
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Old 02-16-2007, 07:22 PM
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never thought of that... that makes things go faster... and only have to go 1 full rotation versus 2 or more to get all the cyl...

race 51 royal purple is SIMILAR in wt as 20/50W BUT it is actually closer to 35/50... just because its got 500 hp doesnt mean that it needs more oil thickness.... besides a lighter oil will cool the engine more and actually allow for better more consistant lubrication due to its abilty to get through the journals and tight tollerances easier than a heavy oil... ESPECIALLY when cold.... and oil in 145-160* engines to begin with doesnt get very warm..... THEN add in the fact that yu all run oil coolers....... oil temps around 120-160 arent all uncommon.... which means that the oil is THICK and may not slide through the .0025" clearences as efectivly as say race 41 (15/40) or even a true 10/40 10/30.. and when does all the wear occur in an engine.. AT STARTUP!!!! not on top or at peak TQ... its when CHIT is dry..... and lacking lube...

Last edited by npartin; 02-16-2007 at 07:28 PM.
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