Piston rings

[Mallett]

So bought new rings, ring tool, cylinder hone, gaskets and the wrong ring compressor. Trying to figure out how to make one. I’ve honed the cylinder cleaned the faces of the motor. Any advice on getting this back together or something else I should be thinking about?

[Gary Haight]

In a pinch I have used zip ties around rings. Once that ring is in cylinder, cut it off and proceed to next ring. Definitely not the best way to do it by any means but in a pinch it worked when the correct tool was left at home.

[Mallett]

How about the ring gap can’t find a number in the book.
Thanks going to try buy the right one.

[Mallett]

The gap is .021 with the rings inside the cylinder one that didn’t get stuck. Just make them the same? Thanks

[labrador-guy]

You might try a hose clamp on your rings.  Just don’t tighten it to much.  Just enough to get it started in the cylinder then loosen it.

dale

[Tubs]

Mallett wrote:

So bought new rings, ring tool, cylinder hone, gaskets and the wrong ring compressor. Trying to figure out how to make one. I’ve honed the cylinder cleaned the faces of the motor. Any advice on getting this back together or something else I should be thinking about?

Ring Compressors. The one in the yellow box I’ve had close to70 years. No good for outboard motors. I had been using these hose clamps till someone on here said these plastic ones work well. So I tried them. IMO they do work well. There on eBay for less than $15.00. May find them cheaper if you like to shop around.  

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

[Mallett]

Thanks again Tubs. Any help with the ring gap?

[PM T2]

FWIW I’ve never used a ring compressor on any outboard motor I’ve ever worked on. Not even the Mercs. The bores usually have a chamfer at the base of the cylinder wall. I use it to my advantage to help compress the ring while inserting the piston into the bore(s).  The only tool I use occasionally is a flat screwdriver with some masking tape on the blade tip. Patience, knowing what the ring is trying to do while you’re guiding it toward what you want it to do, and developing a feel for the operation are the main elements. I’ve broken lots of rings getting them off the piston, but never broken one while installing. Hope this helps.

Best
PM T2

He's livin' in his own private Idaho..... I hope to go out quietly in my sleep, like my grand-dad did..... and not screaming, like the passengers in his car...

[eltoquad]

I’ve never used ring  compressors on a out board either until I was trying to assemble an early Koban twin. Pistons are installed from bottom of bore inside the crankcase and the rings are 5/8″ wide!! I had to machine a special ring compressor to get the rings into the bore.

[Tubs]

Mallett wrote:

Thanks again Tubs. Any help with the ring gap?

Its been suggested to me that .004 per inch is the gap to shoot for if you don’t have a factory spec. Its what I go by. RW’s recommendation of .005 per inch is good as well. The rings expand from the heat, so a couple thousands over is better than not enough. Its a bad thing if the gap closes up, and the rings bind in the cylinder. You should use your best judgment. I’ve pinched rings in with my fingers in the past. As you get older you’ll find that things that use to be easy begin to get more difficult. For me those $15.00 ring compressors make getting the rings in a cylinder really easy again. I wouldn’t have mined if someone had told me about them sooner.  

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

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