Compression test, no cam?

[eagle mark]

Got a motor here I'd like to compression test looking for a bent valve. What should I expect without valves opening? Motor would not run and had a huge lift cam. When he installed it he did not degree the cam or check valve clearance to pistons. I'd like to see what compression says then I think I still have a hose to insert air into cylinders to look for air out intake or exhaust.

 

[Thunder]

Dont know how you can do a compression test with no cam. You need to be able to get air into the cylinder through the intake to properly do a compression test.
A leak down test would be your best bet to see if there are any bent valves.
If you dont have a leak down tester/compressor. Might try spinning the engine over and see if air is getting sucked in and blown back out the intake /exhaust manifolds or ports. That would tell if there was a bent valve.

 

[eagle mark]

I was just wondering. I do have a leak down tester. Thanks!

 

[Blue85]

Leak-down test would verify that your valves and rings are sealing.

You *might* be able to a compression test by finding BDC with an open sparkplug hole, then screw in the gauge and turn the engine over. It's not really a fair test because the gauge normally finds the "peak" of several compression strokes and here you just have one shot at the air. Here the pressure would decrease a little on each revolution. The only thing useful about the readings is that you could compare the cylinders to each other.

 

[eagle mark]

Well I did a little of everything and could not find anything wrong. So the new cam is in and just about ready to run!