It would be nice if we could get the names of the places to avoid.
Or at least a list of who to use.
I’m getting ready to send some cylinders out to get replated for an engine going to Mexico City and I really can’t afford for it to go bad.
I need to be able to trust the Ra since I gave no way of checking.
Thanks
Tony

Know this is an issue and I don’t wish to distract from it. Three weeks ago, Millenium said that they only finish Nikasil cylinders to ~15Ra. Two more calls and got to a rep that said they could do it to 6Ra. That appears to be the pattern that’s now well established. More than capable, but wont default to finish required by these engines unless specified. Feel terrible for those who relied on a third party service that didn’t so specify.

KTL raises a good point that required finish is determined by ring choice. That’s less discussed and documented if not using Goetz, as an example.

I called Millennium myself earlier this year to ask if there had been any improvements to correct the problems we were having, because US Chrome while doing a decent job not perfect but decent has not been that fun to work with this year but there work is OK. The person at Millennium and I quote " said William we do MILLIONS of cylinders a year and it is perfectly acceptable for a few to have problems" just deal with it....... I will and I cant use Millennium as I view it to be a problem if the coating falls off.. I am close to a solution as we're needing them for about 50 motors. I like Mahle but the supply is totally unreliable. I had good luck years ago with Millennium years ago, but things change... Earlier in the tread Harvey said Nickies was on top of this with millennium and have no problems...... I disagree as of last week.. I will find a solution and I am close... William Knight

I think its important to identify the problem you are having and not bring another issue into the fray.

We have had problems with the finish of cylinders but never, have we had any issues when we have sent cylinders ourselves with our PO and spec's. Only times we have and the only issue was the finish when the cylinders were supplied by a 3rd party. We have never has issues with the Nikasil coming off.

3rd party parts houses should not be involved in supplying outside labor for any work. Plating, machine work or whatever. When something goes wrong and it can sometimes, you need to talk to the expert not the middle man that usually has no clue about what has gone wrong or how to fix it.

Like anything else you buy in from a sub, it must be specified what end result you want and inspected before use. If you accept what you get and do not ask for specific end results, then you are the problem not the supplier. Take responsibility here.

I suggest a simple solution. Ask for the coating to be applied, if 15 is the best that can be offered, leave some extra material on the inside diameter, final hone to size and the required finish number yourself, or find a company that will.

Maybe this is a service we should supply as we do a lot of honing of the water-cooled cylinder sleeves for another company.

Well said and agree. Sadly, took a few people to experience the pains of this for it to be documented and known

We may also want to include the JE piston as a culprit. The upper portion is typically much smaller in diameter than the skirt. The pistons rock far more than the original KS pistons. This places extra burden on the rings until the pistons warm up.

Perhaps a lower coefficient of expansion alloy would allow less “looseness” at the top of the piston and less tipping. Resulting in better break in and sealing.

Je adds about .040 clearance above the top ring, I see no benefit to this unless your selling oil..