Vanguard question

[Sam Mac]

If you have a leak down tester use that. I don't have one so I pull the push rods that way it don't have to worry if the valves are closed or try to hold it from rotating.

[Leadslingingdaddy]

Yea that would have been good info to have off the start.....

[ihcc1]

#2 cylinder had very slight leakage at the intake valve. I will relap that valve and check it again.

[ihcc1]

I'm having to test this cold. Both cylinders have slight leakage into crank case "blow by". At 100 psi I here a slight hiss from inside the case. Shouldn't there be slight ring leakage on a cold engine? I don't mind replacing rings but don't want to repair a none problem.

I have up to 145 psi. I think I will turn the regulator up and try listening again. This is new to me so I'm having to feel my way through it.

The leak down tester I bought was from harbor freight and the gauge thats supposed to give a status reading was defective out of the box. I'll have to return it and try again.

[J-Mech]

Sam's way of testing is the most efficient. Cylinder leak down test tools are a huge waste of money.

Do you know what piston ring are, and how they are installed? There is a gap at the end of them when they are in the engine. On new rings, the gap is several thousandths. You think air can get through a gap like that? Yes.... it can. So, yeah, it's going to leak into the crankcase some. That's why I hate leak down tests. You can determine the same thing with a fitting in the spark plug hole and just air. My problem is, I don't hear as good as I used to, and I can't always hear the leak. That's where a smoke machine comes in handy.

This is a 2 cylinder engine that's easy to work on, and parts aren't that costly. Take both heads off, true them up, fix the blown seal, take out that second vent that doesn't belong, clean up the filter housing and be happy. Lapping those valves is a waste of time. You lap new valves. Lapping old valves is like sanding wood with 5000 grit sand paper. Yeah, you take off some material, but it's going to take a lot of work to sand the board.

[ihcc1]

Jmech

You make some very good points! What is your response to my original concern? The fact that running the engine for a few moments fills the crankcase breather and then gets sucked into the carb. It wouldn't take long to suck out half the oil in the crank case. That is my issue I don't want to produce a locked up engine for all my efforts.

Thanks, Bob

[Sam Mac]

OK I'm going to make this easy. When a Vanguard pukes a head gasket the air is pushed into the crankcase it then exits through the vent that exits into the air cleaner housing and it blows a crap pot full of oil into the carb intake. This one would almost choke out the engine. I hooked up a hose to a small pail just to test the engine.