Evenrude 115 1979 Compression Question

[gearyg]

Hello, does any one know what the ideal compression should be on this motor. I just did a check and cyclinders 1 & 2(the higher ones) have 120 and 3 & 4 have 130....is this good or bad....what is the spectrum between good and bad compression....thanks.

 

[Theoutdoorsman]

Re: Evenrude 115 1979 Compression Question

gearyg.............. Your good to go. That's excellent compression. Is this a recent rebuild? Here's a little advice for you............ Make the use of SeaFoam a regular part of your preventative maintnance. These older crossflows are great motors but are notorious for collecting carbon deposits in the exhaust. If neglected, this build up of carbon deposits COULD result in broken piston rings and will require a rebuild.The SeaFoam will help keep these deposits at bay.Take a look at the frequently asked questions board and look for "Decarbing". You'll definitely be glad you did! Do yourself a favor and read that topic. If this post scares you, well, that's a good thing. If it makes you aware that you should keep these deposits under control, even better. You'll then have a reliable outboard that will likely last you for many years to come, with the correct set-up of course............................. ALAN

 

[gearyg]

Re: Evenrude 115 1979 Compression Question

I know it was rebuilt, but not too sure how long ago or how much use....however, great advice...considering I troll alot Decarbing should be a must for me.....thanks.

That was a great Decarbing topic by the way.....

gearyg.............. Your good to go. That's excellent compression. Is this a recent rebuild? Here's a little advice for you............ Make the use of SeaFoam a regular part of your preventative maintnance. These older crossflows are great motors but are notorious for collecting carbon deposits in the exhaust. If neglected, this build up of carbon deposits COULD result in broken piston rings and will require a rebuild.The SeaFoam will help keep these deposits at bay.Take a look at the frequently asked questions board and look for "Decarbing". You'll definitely be glad you did! Do yourself a favor and read that topic. If this post scares you, well, that's a good thing. If it makes you aware that you should keep these deposits under control, even better. You'll then have a reliable outboard that will likely last you for many years to come, with the correct set-up of course............................. ALAN

 

[Theoutdoorsman]

Re: Evenrude 115 1979 Compression Question

Your welcome........................ ALAN

 

[DJ]

Re: Evenrude 115 1979 Compression Question

gearyg,

Alan, mentioned "set up", in his advice.

I believe he means that you also prop it correctly. That engine needs to be able to turn a minimum of 5500 RPM, with a light load. Anything less will "lug" it and hasten deposit build up.