Quote:
Originally Posted by ericwoo
I am ordering a leak down tester to see if there is leakage in that driver side head. Hopefully I should get that complete early next week.
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There's a hundred companies selling leakdown testers for automotive use, and
NONE of them are trustworthy...until you've either confirmed them with a
Master Orifice, or you've
tested known-good cylinders of the same approximate bore diameter as what you have. If you test enough engines, with enough different bore sizes, you can have a good idea of how your leakdown tester works--but the Master Orifice is WAY faster.
There are no "industry standards" or legislation/regulation of automotive leakdown testers. They build whatever they want, and depending on how they're built, they can give WILDLY different results on the same cylinder.
However, the FAA has standards for AIRCRAFT piston-engine leakdown testers, and the ones suitable for 5" bores and smaller aircraft engines are also suitable for automotive engines.
Even better, Continental/Teledyne came up with the "Master Orifice", a calibrated leak that is the equivalent to the MAXIMUM leakage allowable in their engines. You'd plug a leakdown tester into a Master Orifice, note the reading. Then if the engine has less leakage than the Master Orifice, it's considered "good". My standards are higher than that, so I only allow about 2/3 the leakage of the C/T Master Orifice, and only then if it's past the rings--not past the valves, or into the cooling system.
I bought an aircraft-spec leakdown tester with a built-in Master Orifice a dozen years ago. Very recommended. It normally ships with an 18mm cylinder adapter, they'll supply a 14mm automotive adapter on request...or buy several sizes and be able to do motorcycles and old Fords and Mopars.
https://www.aircraft-tool.com/detail?id=2EM
Quote:
Originally Posted by ericwoo
The next thing I realized, is the pushrods are indeed a little too short. See the test I did in the attached photos
Passenger Side
Driver Side
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The first witness mark isn't readable, the second one is not
bad, but wider than optimum. Adjust the pushrod length to minimize the sweep (narrowest pattern) even if it's somewhat off-center on the valve tip.