Compression on 1979 Merc. 115HP

[Kenny Sorweide]

My neighbor wants to trade his 1979 115HP Mercury for a 75 HP Chrysler that I have that is in very good shape. His Motor has factory power trim and tilt. I ran a compression check and dry they read from top to bottom 90# 110# 100# 100# 75# 100# I added a few squirts of oil to each Cy. and that changed the reading to (again from the top) 150# 175# 160# 175# 130# 125#. This to me would indicate that it needs a overhaul. He has an extra complete parts motor that will go with it. I don't know that much about Merc as I have always had OMC, so I am turning to the forum for advice. I would not need this motor for a few years and could do the work on it myself. Am I biting off more then I would be able to handle, and would the price be way to much. I have a 1967 Glasspar Seafair Sedan that is in excellent condition that I would love to put a "tower of power" on. Thanks in advance for any comments and advise.

 

[jheron]

Re: Compression on 1979 Merc. 115HP

As long as she isn't to coroded you will have no regrets! I just did a complete overhaul on one of these girls my self and she is running like a top I would try and give her a good decarb before I split her open though <br />regards Jon

 

[MortenH]

Re: Compression on 1979 Merc. 115HP

The corrotion is th ebig issue here. I am a novice, but this winter i spend several hours in my garage rebuilding a 1984 I6. As long as you have a good manual and get help from the pro's here, this is a job that is manageable.<br /><br />-M-

 

[Clams Canino]

Re: Compression on 1979 Merc. 115HP

Yup!<br /><br />-W