Did I Do This the Hard Way?

[drifter]

1957 Sea King 5hp. Saved from the dumpster. Stuck. One piston corroded below the bottom ring grove and cylinders surface rusted. Ran a glaze-breaker in the cylinders and they cleaned up nicely. One replacement piston and new rings for both pistons. Since this engine has no removable cylinder head, piston assemblies must be installed through the bottom of the cylinders. I noticed the cylinder bottoms are chamfered to ease the rings into the piston ring grooves as the piston is installed. But….holy cow! is that difficult. My little fingers are going to be sore as this task took me nearly an hour. Prior to installation, I checked the piston fit with no rings (slid smoothly), checked the new ring’s end gap in the bore (fine), made sure the rings were clear of the locating pins, lubed everything up with 30 wt. oil.
Everything moves smoothly ….. now.
I’m used to engines with removable heads and the "fingernail" method of piton/rings assembly installation.
Is there a trick to installation piston assemblies in non-removable head engines such as this 57 Sea King 5.0hp? 😳
Drifter

[frankr]

They had tapered ring compressors for them back in the day.

[billw]

Mercs are like that. My feeling is holding the two assemblies aligned is the hardest part. If you can find a comfortable way to do that, the rings are the easier part. I usually use some hardwood sticks to push the rings in.

Long live American manufacturing!

[wiscoboater]

Don’t know if this will work in your application, but the guys at my local lawn equipment repair shop use zip ties as ring compressors. as the ring enters the cylinder, they cut it off with a razor knife. I watched him do it a couple times. It works well when big fingers won’t fit in small cases.

[ken-w]

Try making ring compressors out of aluminum flashing cut into 1/2 or 3/8 strips that can be wrapped around the piston rings, then pulled out when the pistons are in place?

[Tubs]

A "Boathouse Repair" is one that done without having tools or the skills to do it properly.

• This reply was modified 6 years, 9 months ago by Tubs.
• This reply was modified 4 years, 5 months ago by Tubs.

[frankr]

Folks, that had me scratching my head for awhile, till I Googled "host" clamp and realized he meant "hose" clamp. GREAT idea!!!

[Tubs]

A "Boathouse Repair" is one that done without having tools or the skills to do it properly.

• This reply was modified 6 years, 9 months ago by Tubs.
• This reply was modified 4 years, 5 months ago by Tubs.

[beerman57]

I see your t-bolt hose clamp pic, I like that idea for ring compressors! Wish this came up before I did 2 OMC 10hp motors this summer, new rings will shave a couple layers of skin off your fingertips.

[jeff-register]

Frank,
I remember a guy who worked with us at the Corvair shop. He had a collection of tapered ring compressers for different bores for Chevy’s. They were very nice to work with. Start the piston in the tool, insert into the bore & tap the piston in, Very easy. Only item is the ring locators in the 2 strokemotor. I like the idea of seeing them compress into place using 1/4 sections of 1/2" PVC pipe & zip ties. A guy can see them go into place & not hurt anything using plastic against the metal parts.
I had a hard time with a KF5 until I built this tool. 😉

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