Re-ringing a chrome bore cylinder

[Fastjeff57]

Merc 25. Do you hone it, or just clean it up with solvent before putting new rings in?

Thanks,

Jeff

[Bill Van Steenwyk]

I have no personal experience other that trying to hone one a couple of times with a regular ball hone. After replacing the ring, the engine only went a couple of laps and lost all compression and would not start again. I do know (because I asked) that when the various companies that do replating of cylinders fit a piston (if furnished) to the replated cylinder, that they use a special, very expensive "diamond hone" to get the final skirt to wall clearance.
Perhaps you could talk to someone in tech at one of these companies and they could help you. Google "cylinder replating". I always had very good luck with a replated cylinder when sending in a piston along with the cylinder so they could hone and final fit to skirt clearance specified. The honing with a regular ball hone wore the ring out in a couple of laps as previously mentioned. It would seem if the cylinder is "glazed" that to seat a new ring that would need to be prepared properly. Don Nichols in Baton Rouge La. does lots of Merc V-6 cylinders and he has the proper hones to do that type of work with, and also for smaller cylinders. If you want his number PM me and I will put you in touch with him.

[john miffco]

when replacing the rings on a chrome bore motor
just need to set block in a varsol vat and use a red or brown scotchbright pad
to remove the glaze only
same as nicasil,,,,,,,,,,
both metals are very hard and dense

the reason when final honeing a plated cylinder with a diamond hone is
a standard honeing stone weres out very fast and does not stay as true as it is wearing so in reality the diamond powder in the better stones last longer
and stay flatter,,,,,,,,,,,,

a multiple ball style hone takes out all so minute amount of metal when used
that is why it is refered as a deglazing hone
and is not recomended to use on a 2 stroke motor of any cylinder finish

the reason you probably lost compression very quickly
is that the ball hone wears out so fast it is very difficult to clean
all the grey in the cylinder after honing makes you think it took out metal
but in reality its the soft stones residue
its very difficult to remove all the resudue after honing a 2 stroke
it goes inside the tranfer,boost,fingerports
and can wash it down numerous times
and still get grey on a white towel when wipe out cyl and ports

so the residue left imbedded in the cyl and where you cannot get to clean
is washed back into the cyl from the fuel charge
and is like sandpaper when start the motor up on the cyl and rings
rings and comp goes down
john

[Bill Van Steenwyk]

John:

Thanks for the info on what the problem was with the ball hone. I thought it might be something like that, as the ring wore out in just a lap or two just like the cyl had valve lapping compound in it. Since silicon is used for that purpose or as sandpaper I guess that is what happened. We did wash the cyl as good as possible with brake and carb cleaner before reassembling, but due to time contraints changing pistons between heats, experienced the problem mentioned. I had never had any experience with cylinders with no liners before and did the "stupid" I guess.

Again thanks for clarifying. I will remember the tip about the scotch pads.

[Fastjeff57]

Thanks, John. Will do.

Jeff

[john miffco]

we all have done it
especaily at the races site doing a piston swap
most common lubricant on hand at a race site is wd40
so when used to oil cyl with ball hone,,,,,
found out the residue does become a lapping compound

i have balled honed to help campher the ports
power washed block with water and degreaser
set it in vat and varsoled,,,,,2-3 times
and still get grey on white cloth when wiped,,,,,,,,
and thats here at a shop with all the cleaning tools and time
very hard to get all out

on chrome and nic,,,,,
the scotchbrite with varsol leaves minimum residue
easy to clean when just swapping rings
and not trying to get whole cyl to look the same
plated cyls will have wear marks on it from piston where it touches or rides
just want to wipe off glaze,,,not remove any metal

not like when working with a steel cyl
and hone till all cyl same finish look