Retired Wrencher 4,876 #1 Posted June 6, 2017 I am looking at a B 80 that has no compression. Other than blown is there something to look at like a stuck Valve? Thanks in advance. Share this post Link to post Share on other sites
Racinbob 10,277 #2 Posted June 6, 2017 Possibly the ACR is stuck. 1 Share this post Link to post Share on other sites
pfrederi 17,147 #3 Posted June 6, 2017 If the engine can crank over do it and feel the exhaust and carb air intake. a stuck valve would have some puffing out one or the other. Broken ACR would puff out the exhaust. 1 Share this post Link to post Share on other sites
Achto 26,556 #4 Posted June 6, 2017 The easiest way to find the issue would be to do a leak down test, if you have a tester available. With out a leak down tester, then the next way to tell is to pull the head off of the engine. Look for piston wash (if the top of the piston looks clean then the rings are bad). If there is little to no piston wash then I would look into the valves or ACR. 1 Share this post Link to post Share on other sites
WHX?? 46,774 #5 Posted June 6, 2017 If the rings were bad she might have some compression but a stuck valve or ACR would have none. Time to pop the head or look inside the breather cover and see what shakes. 2 Share this post Link to post Share on other sites
Retired Wrencher 4,876 #6 Posted June 6, 2017 (edited) Sorry not sure what a acr is excuse my ignorance. I saw the add today so considering the buy. Edited June 6, 2017 by Retierd Wrencher Share this post Link to post Share on other sites
pfrederi 17,147 #7 Posted June 6, 2017 ACR AUTOMATIC Compression Release. Pops the exhaust valve up briefly during the compression stroke at very low RPM makes it easier to crank the engine. 2 Share this post Link to post Share on other sites
Retired Wrencher 4,876 #8 Posted June 6, 2017 Ok thanks. Was thinking on this line Share this post Link to post Share on other sites
BOB ELLISON 2,976 #9 Posted June 6, 2017 I think WHX11 has it. I would pull head and look for a stuck valve. 1 Share this post Link to post Share on other sites
N3PUY 1,031 #10 Posted June 6, 2017 I put my money on a broken connecting rod! If the piston is not going up and down then there's no compression. 1 Share this post Link to post Share on other sites
WHX?? 46,774 #11 Posted June 7, 2017 Well nows there's a thought ...N3 ..has a point there. ..might need some clarification here Wrencher 1 Share this post Link to post Share on other sites
chip61 655 #12 Posted June 7, 2017 I was sure my K341 threw a rod, turns out the piston broke in half. Bottom half still moved smoothly in the cylinder. No other damage, new piston and rod and it was back to work! 2 Share this post Link to post Share on other sites
Retired Wrencher 4,876 #13 Posted June 8, 2017 Thanks guys Trying to look at it. But some times it is hard to do so. Share this post Link to post Share on other sites
