Valve Clearance Check

[Geeman]

I don't own an RV, but I did pay my $25 donation to the website and I will own an RV soon, so I am going to ask a question about my C172 engine. I hope I don't get kicked off.

My question is, how do you get the lifters bled down to check the dry clearance on a Continetal 0300 with the cylinders on?

I was told by an A&P to rotate the prop until the valve is open and leave it there a few minutes and it will bleed down. Then you can check the clearance between the rocker arm and the valve.

I was told by another A&P you have to pull the cylinders to get to the lifters to get them bled down.

What say you?

Thanks in advance for any input.

 

[rocketbob]

This works most of the time if you leave it up on the cam lobe with the oil warm.

 

[mahlon_r]

You can bleed the lifters with the cylinders on the engine as described, but you must maintain pressure against the rocker arm against the lifter as you rotate the engine to check the clearance. If you don't maintain a push against the lifter it will likely draw some oil back in as you rotate the engine and spoil the cold clearance check because the lifter will then not be fully bled down.
Good Luck and Merry Christmas,
Mahlon
"The opinions and information provided in this and all of my posts are hopefully helpful to you. Please use the information provided responsibly and at your own risk."