Re: compression top 90lbs bottom 70lbs
1978 Sandollar <br />Captain <br />Member # 34021 <br /><br /> posted November 24, 2003 08:29 PM <br />--------------------------------------------------------------------------------<br />Hi,well I have a 1979 55hp evinrude 2 cycile and it has very little power it starts great sounds good but it will only run about 15 to 20 mph so I check the compression and the top is 90lbs and the bottom is 70lbs so my questions is this ok for the year of the motor our is time to have it rebuilt our could it be the carb thats bad? well thanks for the help and happy holidays to every one!!! <br />--------------------------------------------------------------------------------<br />Posts: 38 | From: CA | Registered: Oct 2003 | IP: Logged <br /> <br />OutboardJim <br />Tackle Shop Admiral <br />Member # 18214 <br /><br /> posted November 24, 2003 10:37 PM <br />--------------------------------------------------------------------------------<br />Hey sandollar...happy Turkey Day to you to. <br /><br />Have you done a decarb lately? Yer a little better than 10% difference in compression. Do a decarb then do a warm compression test. See what pops up. Might just be a leaky head gasket.<br /><br />Keep us posted...thanks.<br /><br />--------------------<br />OBJ<br />*When all else fails...use the manual.<br /><br />--------------------------------------------------------------------------------<br />Posts: 2194 | From: Rayland, Ohio | Registered: Dec 2002 | IP: Logged <br /> <br />1978 Sandollar <br />Captain <br />Member # 34021 <br /><br /> posted November 24, 2003 10:45 PM <br />--------------------------------------------------------------------------------<br />Thanks OutBoard Jim! but how do you do decarb our what is that thanks agin. <br />--------------------------------------------------------------------------------<br />Posts: 38 | From: CA | Registered: Oct 2003 | IP: Logged <br /> <br />OutboardJim <br />Tackle Shop Admiral <br />Member # 18214 <br /><br /> posted November 24, 2003 11:02 PM <br />--------------------------------------------------------------------------------<br />Go to your local marine store and ask for a can of engine tuner. Tell them you want to decarb your engine. There are several brands, Bomby, Sea Foam, Merc has on also. But they all do the same thing. Get rid of built up carbon in the engine....<br /><br />Follow the directions on the can as different brands recommend different soak out times.<br /><br />Basically, hook the hose up to the engine, start and till engine reaches operating temp. Shoot the decarb into the carbs. You'll probably will have to idle up a little to keep the engine from stalling. Shoot the whole can into the carbs. Going to smoke like crazy but that's OK. When ya' get most of the can in, you let the engine stall. Follow directions on the can for soak time. Restart after soak and blow out losened carbon. Going to smoke some more. The do the compression test.<br /><br />--------------------<br />OBJ<br />*When all else fails...use the manual.<br /><br />--------------------------------------------------------------------------------<br />Posts: 2194 | From: Rayland, Ohio | Registered: Dec 2002 | IP: Logged <br /> <br />1978 Sandollar <br />Captain <br />Member # 34021 <br /><br /> posted November 24, 2003 11:08 PM <br />--------------------------------------------------------------------------------<br />Thanks for the reply OutBoardJim!! I don't have a manuel yet but do you know if I need to take the cover of the carbs? To spray the can of decarb. <br />--------------------------------------------------------------------------------<br />Posts: 38 | From: CA | Registered: Oct 2003 | IP: Logged <br /> <br />OutboardJim <br />Tackle Shop Admiral <br />Member # 18214 <br /><br /> posted November 24, 2003 11:19 PM <br />--------------------------------------------------------------------------------<br />Yeah sandollar...just remove the screws in front and it'll come right off.<br /><br />--------------------<br />OBJ<br />*When all else fails...use the manual.<br /><br />--------------------------------------------------------------------------------<br />Posts: 2194 | From: Rayland, Ohio | Registered: Dec 2002 | IP: Logged <br /> <br />1978 Sandollar <br />Captain <br />Member # 34021 <br /><br /> posted November 24, 2003 11:20 PM <br />--------------------------------------------------------------------------------<br />Thanks aging I'll get a can and try it and I post a reply thanks again... <br />--------------------------------------------------------------------------------<br />Posts: 38 | From: CA | Registered: Oct 2003 | IP: Logged <br /> <br />Mod2 <br />Moderator <br />Member # 25978 <br /><br /> posted November 25, 2003 12:31 AM <br />--------------------------------------------------------------------------------<br />Sandollar....I noticed that this post is a repeat of a previous post by you. All you need to do is answer yourself and it will bump back to the top. Just click on "post a reply" and put a "^" in the answer area. This will keep your post together. Thanks. <br />--------------------------------------------------------------------------------<br />Posts: 150 | Registered: Jun 2003 | IP:
