whtractors24 3,399 #1 Posted September 23, 2013 have a 1978 c-81 the machine runs good but smokes. so I decided to do a compression test on it only has 13-15lbs of compression while cranking over 3 times? thinking about pulling the head to see what's going on anyone have any thoughts on this! I always thought at that low of compression it wouldn't run. Any help is appreciated. Share this post Link to post Share on other sites
Fordiesel69 271 #2 Posted September 23, 2013 Before pulling the head, put about three pumps of oil into the sparkplug hole. If it raises considerably, you have a ring / cylinder problem. If it says close to 15 then you have a, incorrect adjusted ACR or a valve problem. If you want to just pull the head anyways, it certainly won;t hurt to do a valve job and decarbon. Share this post Link to post Share on other sites
Fordiesel69 271 #3 Posted September 23, 2013 With a properly working ACR, it will be low, but 13-15 is way to low. Does the engine run? And does it have normal power? Your guage could be suspect if it does. Share this post Link to post Share on other sites
