Piston ring compression tools

[Grumpy Bear]

74 Merc 500 50hp. So, can you reinstall the pistons into the cylinders with standard piston ring compressors (like pic?), or do you have to have the special Merc ring compression clamps to get the job done (pic of 3) ?

Thanks again!
Kevin

 

[gm280]

74 Merc 500 50hp. So, can you reinstall the pistons into the cylinders with standard piston ring compressors (like pic?), or do you have to have the special Merc ring compression clamps to get the job done (pic of 3) ?

Thanks again!
Kevin

I honestly don't know about your 50HP, but I was able to install the pistons with rings with my fingers when I rebuilt my 40HP Johnson. So I really don't know...

 

[Faztbullet]

To do it correctly you need the Merc compressors as you install all 4 pistons and crank at the same time .I have heard of people install them one at a time and then installing crank and bearings but if done this way you have no way to torque the rod nut to spec's. What did you decide on piston/ Hope it wasnt to sand it as suggested...

 

[buzzm19]

I installed my pistons one at a time on a 72 l6 140 hp and on the rod bolts I welded a socket to a box end wrench, calcuated for the dstance and torqued the bolts down and worked great. Buz

 

[buzzm19]

I meant nuts not bolts, I always get the names confused sorry Buz

 

[rookie456]

I just rebuilt a 1980 80hp Merc, 4 cylinder, with 4 new wiseco 2 ring Pistons. I went back and forth on how I was gonna install the Pistons. I didn't want to spend $130 for a set of ring compressors I was only gonna use once, so I decided I would assemble the whole crank with the Pistons and try to instal by hand. I first made sure that all my rings were lined up with the pins on the Pistons. I held the crank over the block and slowly lowered it. Piston 1 went in cylinder 1, and the taper at the top of the cylinder compressed both rings, then cylinder 3, then 2, then 4. I was surprised how easily it went together. I coated the cylinders and Pistons with 2 stroke oil before installing, and made sure I got a good look at each ring as it was entering the cylinder to make sure it was lined up with the pin.