Is it neccesary to deglaze a good cylinder for new rings Need advice Joe Tony AnyAll advice appreciated

" Hi,

I ran into a prob

" Hi,

I ran into a problem with one of the pistons on the merc 115 L6 that I'm rebuilding; the pin was pushed in, and the ring has spun, luckily without breaking. Before I took it apart the compression was 122-127 cold. I am replacing a stripped crank and had not planned on doing anything else other than cleaning off carbon and re-installing everything. The piston that was in there before was of standard size, and I picked up a wiseco to replace it. The directions that come with the piston are telling me to hone/de-glaze; is this neccesary if the cylinder was good? What will happen if I don't de-glaze?.. What exactly is de-glazing, and is there a way to do it without the use of power tools?

Thanks for any/all advice,

Jon "

"Jon,

You should de-glaze t

"Jon,

You should de-glaze the cylinder. This is a simple process. You can get a cylinder honing tool at any automotive parts store. It consists of three grinding stones on spring loaded arms. You insert it into the cylinder and turn it by hand. I generally turn it about a quarter turn in each direction, pushing it to the bottom in one direction and pulling it to the top in the other. Do this about ten times, and then change change the direction of movement. Rotate the tool a quarter turn and repeat. The idea is to remove the glaze by using a crisscross pattern on the walls. You don't want to overdo this, because you might take too much off of the walls, and then the piston will be too loose.

"

" Tony,

Scraping the cy

" Tony,

Scraping the cylinder walls is scary stuff, but doing it by hand doesn't sound too bad. I have seen those hones in automotive shops in the past, they are fairly modest in cost as well. I'm wondering how rough the cylinder should look when I'm finished, will there be a crisscross pattern visible in the cylinder? What do you recommend for cleaning when I'm done? Thanks again,

Jon "

"Jon,

The cylinder wall wil

"Jon,

The cylinder wall will be smooth, but you will see the crisscross pattern left by the stones. You should use some oil on the stones and walls while you are de-glazing, and when you are finished, you can clean everything with warm, soapy water. Dry all and coat with some two cycle oil.

"

" Tony,

Thanks again,

" Tony,

Thanks again, I'll be giving it a shot after I post this.

Jon "

" Jon,

Not too sure about t

" Jon,

Not too sure about this however, it is something to think about: the forged Wiseco piston will require more clearance than the stock cast one. Find a machine shop to fit the piston in. I had my block honed and it was only $8 a cylinder. I was told to never mix cast and forged pistons. I would check with a machinist to be sure. If you are putting the other pistons back in the same cylinders, you shouldn't need to hone them all.

Just my $.02 worth. I trust my machinist to let me know how to do things right instead of doing them twice.

Kirk "

" Kirk,

I'm not

" Kirk,

I'm not sure if you are still checking this post, but I read your .02 on the forged pistons and here's what I have dug up. Forged pistons cannot be made out of quite the same material as cast pistons; so, generally forged pistons and cast pistons will expand at different rates, which is why the forged piston requires more clearance. The Wiseco pistons are sold by bore size; so, although they require a larger degree of clearance, it is allready accounted for. As far as Wiseco is concerned they are individually replaceable, but I can imagine that mixing forged and cast may not be ideal. Had I have known that at the time, I would have gone with some other aftermarket that is cast. But, too late for that now - I'll be giving it a shot this weekend, wish me luck.

Jon "