[JohnF]

I keep dwelling on the hydraulic lifters after purging the oil system. The Rotax manual at this point suddenly has you running the engine to check them, and repeating that again if necessary....I am concerned...if the max of .02 isn't met (even on a new engine) the manual would have you changing parts out. How did you folks handle this? I talked to some Rotax users who simply ignored the clearance checks on the rockers on a new engine after purging the oil system.

Advise?

 

[rvbuilder2002]

I keep dwelling on the hydraulic lifters after purging the oil system. The Rotax manual at this point suddenly has you running the engine to check them, and repeating that again if necessary....I am concerned...if the max of .02 isn't met (even on a new engine) the manual would have you changing parts out. How did you folks handle this? I talked to some Rotax users who simply ignored the clearance checks on the rockers on a new engine after purging the oil system.

Advise?

The check is to verify that the lifters have fully pumped up with zero clearance between the valve and the rocker arm (actually no more than .002")
Basically what the Rotax documentation is saying to do is remove the rocker covers (they reinstall with reusable O-rings). Rotate the prop so that you see that neither valve on a particular cycle is opened. Push on the push rod end of both rocker arms with the end of a wooden mallet handle and verify that the hyd lifter is pumped up tight (no movement in the rocker arm). Reinstall the rocker covers.

 

[JohnF]

Thanks, Scott. I am going to repressurize the engine oil and recheck them, but just to nit pick the max is 0.5mm which is about .02 inches which one of mine did not meet...perhaps another oil pressurization will fill the lifters. thanks for you input, I really appreciate it.

 

[rvbuilder2002]

Thanks, Scott. I am going to repressurize the engine oil and recheck them, but just to nit pick the max is 0.5mm which is about .02 inches which one of mine did not meet...perhaps another oil pressurization will fill the lifters. thanks for you input, I really appreciate it.

Oops bounced on the # keys...meant .020", not .002"