WH1618speed 542 #1 Posted October 11, 2021 Hey everyone, we picked up a C-161 with no compression. We thought the valves were stuck open so we took off the valve cover and the valves were fully functional. So then we took the head off so we could sew what the combustion chamber looked like. We actually found out that the exhaust valve was bent. The previous owner said he put a new coil, condenser, spark plug, and points. Our theory is that the spark plug he put in was too long and it was hitting the exhaust valve and bent it. So we will need to replace and reseat the valve or pull one off of a spare k341 that had a knock and seat that valve in it. The. combustion chambers has quite a lot of carbon we will have to clean up as well. That is why there was no compression because the valve was not sealing off the chamber in the compression stroke causing the engine to spin freely. I know on some if the K341's there was a compression-release system that made starting easier but spinning the engine backwards overrides that system so it still spun freely. Please share your thoughts! 2 Share this post Link to post Share on other sites
Snoopy11 5,718 #2 Posted October 11, 2021 Looks like a good project! Just make sure, before you bolt everything back up, do a quick valve leak test such as I outlined in the following forum... (you actually might want to follow some of the ideas in there, specifically if your valves leak at all). Don Share this post Link to post Share on other sites
squonk 43,806 #3 Posted October 11, 2021 Lapping valves only goes so far. Since yo got lucky that that half the piston wasn't gone or the rod broke, I would spring for new valves and get the seats ground. 2 Share this post Link to post Share on other sites
WH1618speed 542 #4 Posted October 11, 2021 Ok we ordered a new valve. Share this post Link to post Share on other sites
953 nut 59,940 #5 Posted October 11, 2021 While you are at it I would suggest taking a look at the balance gears. Hate to see a good engine get grenaded! 1 Share this post Link to post Share on other sites
WH1618speed 542 #6 Posted October 15, 2021 Hey everyone, update on the C-161, we got the valve in and in runs great. No knocking or smoking so we are in good shape. Thanks for all the advice! Share this post Link to post Share on other sites
Fordiesel69 271 #7 Posted October 15, 2021 What a good score. I got a M14 that a mouse peed on the flywheel and glued the flywheel magnets to the magneto. You got the better score though........... 1 Share this post Link to post Share on other sites
