Rebuilding 1982 Mercury 50HP 4 cyl.

kb5fjx

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I am rebuilding an 1985 Skeeter SF150, it came with a 1982 Mercury 50HP 4 cyl, 2 stroke. I found a new old stock block from the UK for $311. and I plan on getting a rebuild kit with standard pistons. I found that a special piston ring compressor is required, but they have a insane cost. Are their other options available to compress the piston rings, or is there anyone in the Arkansas area that has a set of 4 I could borrow when I am ready to finish the rebuild?
 

gm280

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I have no idea what a "Special Ring Compressor" is or even looks like. Could you educate me with a few pictures?
 

racerone

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Mercury special tools they are !-----The pistons and crank assembly go into the block from the bottom.---------The 4 ring compressors go around the rod and sqeeze rings with long " fingers " and it makes the job fairly easy.-------Compressors are removed when piston enters the cylinder.
 

racerone

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Just use----google------old mercury ring compressors--------Find all you need and video on how to use them.
 

merc850

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You can put the crank and pistons in by hanging them from the ceiling above the block on a chain with hooks; you can lower the assembly one link at a time while squeezing the rings in with your fingers on each piston. A dealer might do the final insertion for you reasonably priced.
Here's a guy with compressors back in '75 4cyl-rings.jpg
 

gm280

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Okay I just watched a video and learned something new today. Looks like it is easier then I initially thought at the beginning of the video. The fact that this engine's pistons and rings installed from the bottom of the cylinders is the reason for the long finger ring compressors. Not seeing this particular block, the rings seem to slide in a lot easier then coming in from a none beveled top end. JMHO
 

racerone

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But factory ring compressors for most all OMC motors and V-6 Mercury motors are nothing but a special funnel and pistons slide right in.
 

kb5fjx

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They run about $200+ dollars a piece, not something I want to spend for a one time deal. There is no "Removable Head" on the older motors that's why is has to be done via the crank case.
91-31461A2-2.jpg
 

gm280

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They run about $200+ dollars a piece, not something I want to spend for a one time deal. There is no "Removable Head" on the older motors that's why is has to be done via the crank case.
91-31461A2-2.jpg

Yea I did see the typical cost and have to admit, I would think on this and have to come up with a way to accomplish the install in some different way. There is always ways. I do like the idea of a funnel type install if the rod ends are not larger then the piston diameters. JMHO
 
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