Does this look like enough compression?

[Igor_toko]

Hi all, I am working on my first engine, a 4 stroke 1 cylinder engine with 15mm stroke & bore.

I have been struggling with sealing the valves for a long time. This is what I have right now, when I run the engine manually with the valves closed, it bounces back, but I hear a bit of a whistle sometimes (not each time I rotate it). I haven't measured the exact pressure, but I read in this forum that the bounce-back is a good indicator. Am I good for the engine to start running, or is this too low of a compression?

Video is attached below. There is a little bit of oil in the cylinder

 

[minh-thanh]

Hi
Personally, I find the compression quite ok .

 

[Igor_toko]

Hi
Personally, I find the compression quite ok .

Hello, thanks for the feedback. I have now changed the piston ring (I use o rings) and the whistling noise has disappeared and it bounces back even more, so hopefully it will work

 

[Nerd1000]

Hello, thanks for the feedback. I have now changed the piston ring (I use o rings) and the whistling noise has disappeared and it bounces back even more, so hopefully it will work

Don't give up on your metal rings, they'll bed in and improve greatly if the engine is able to run.

 

[Igor_toko]

Don't give up on your metal rings, they'll bed in and improve greatly if the engine is able to run.

Hello,

Thanks for replying, I have used O rings on this engine since it's my first one, but I want to update it to cast-iron rings once I get it to run. I've struggled so much with sealing the valves already.

This is what if looks like now when rotating the engine:

 

[minh-thanh]

If it were my engine, I'd be pretty confident it would run fine