Piston Ring Compression Help

[ParamedicCurt]

I just bought a 2003 GTX-DI. Redoing the top end. The crank case is still in the hull. Any tips on how to get the piston rings compressed so I can lowered the cylinders in from above? I'm doing this myself. I've seen lots of videos where guys just squeeze. If I work from the port side, I can't see the notches and the open end of the ring pushes out when I squeeze so it catches on the cylinder and I can't advance it cylinders down. If I work from the starboard side I don't have room to do anything. I'm so close to buying a hoist and taking the whole thing out. But really, it can't be that hard!

 

[Spider4real]

Ive done it by hand and once and had sore fingers after the process with a few curse words inbetween. The next time I used a thick zip tie (actually two of them to make it big enough to go around the piston). It was 5/16" thick. The zip tie holds the rings compressed and it easily slides down as you place the cylinders over it. Works very well and is so much easier. Then just cut them off.

 

[etemplet]

Toughen up. Cut a slot in a 2" x 4" large enough and long enough so you can place the 2 x 4 across the lower casing. I tape the bottom of the 2 x 4 cuz I don't want any wood particles or dirt getting into the engine. The point is that with the slot for the connecting rod to pass, the piston can sit on the 2" X 4" and be solid while you install the cylinder. Main thing is pay attention to the location of the ring alignment pins and make sure you squeeze tight. The Cylinder will slip right on when you get it lined up correctly. DANGER POINT is don't let the cylinder push the lower ring out of the groove. Pay close attention. Patience, feel, and finesse.

 

[ParamedicCurt]

I used both ideas! It definitely helped. God forbid there is a next time (I hope never), I'm going to pull the whole motor out of the hull. I just didn't have a motor lift this time and YouTube makes the in-hull installation look easy.

Thanks y'all!

 

[burtshaver2021]

I don’t know how heavy the 951’s are or the 717’s for that matter. But when I took the motor out of my HX I just lifted it out by hand. Not really that heavy, I did have the exhaust off of it though

 

[mikidymac]

951 is quite a bit heavier than a 720.
Are you having the cylinders bored and new oversized pistons fitted or just replacing rings?