Millenium Cylinder Fine Grit Honing Is the Right Way to Go

[VFR750]

Many thanks to Troy at EBS Racing. My engine doesn't burn oil anymore!

Bottom line: ~800 grit honing of Nikasil plating on Alusil Cylinders is the right answer.

Typical "iron block" 220 grit honing of the Nikasil coating is recipe for rings not seating, oil burning, fouling plugs, general unhappiness. Ask for fine grit honing only. And the standard Goetz rings with JE pistons are just fine.

OK, the back story: I rebuilt my 3.0, three times in 2100 miles.

I got a set of JE pistons, Goetz rings, and Nikasil plated, Alusil cylinders from EBS Racing. 1st build was a full, split case rebuild. ~1100 miles of break-in, and it was burning 1qt every 350 miles. It ran crappy, fouled plugs, and was always wet inside the cylinders. Teardown to the Short Block

Rebuild #2, included refurbished heads (a story for another time ), and new Total Seal piston rings, in manually de-glazed cylinder walls.

Worse than before. 1QT would last maybe 200-250 miles. Blowing smoke continuously, fouling plugs, a horrible mess. I ran it hard and still no joy. after 900-1000 miles, pulled it out and tore down to the short block. Again.

I spoke to Troy at EBS Racing and he said to send the piston and cylinders back and they would get them checked out. Nice!

Machinist inspected the cylinders and said the honing grooves are too deep. Even after 2100 miles and two sets of rings. Looked like the rings were floating, and not seating.

They then sent the cylinders back to Millennium, and had them replate the walls, and specified fine (800?) grit honing, not the typical 220 grit honing. Plus they had the piston skirts coated to reestablish the proper fit. I got them back in ~ 5 weeks elapsed time. Pretty darn fast. I decided to install new Goetz Rings verses the Total Seal rings. Mainly because I don't like the 3-piece assembled oil ring.

The honing was visibly smoother and finer.

Rebuild #3: It does not burn oil.

20 minutes of Break-in with Lucas 30wt Break-in oil. After the first 10 minutes at 2000 rpm, the oil smoke out the tailpipe stopped. Drain and refill with Lucas 10w-40 Hot Rod Oil. Drove it 485 miles and did a valve adjustment. NO oil consumption. I little bit of blow-by as witnessed by vapor in the oil tank. That's it.

I just drove another 100 miles and pulled the plugs. DRY. Still no change in oil level.

Conclusion: The standard "iron block" 220 grit coarse honing of Nikasil plating is not a good thing. The hard Goetz Rings combined with Nikasil will result in the equilibrium being reached long before the cross-hatching has been reduced enough to avoid excessive oil retention. Fine cross hatching (800?) Grit grooves are shallower. And that is the right thing for Goetz rings.

Thank Troy, and EBS Racing, for standing behind their products.

[Dan J]

Glad to hear Mike You are one patient guy!

[porterdog]

Nice ending.

[Trackrash]

That is really good to know.

[chris_seven]

Very Interesting.

220 Grit used to be a standard recommendation for stones used to hone cast iron cylinders using either chrome plated or cast iron pistons rings. I am surprised that this specification is still being used.

Some years ago it became common to add a second op using a 320 or 400 grit to produce a small plateau to aid bed-in.

At 220 grit it wouldn't surprise me to have bed-in period of up to 12 hours and in modern terms this seems unacceptable.

I am not sure what finish is applied to a Goetze ring used in a Nikasil bore but it is unlikely to either chrome or a plain cast iron.

If the rings were moly-coated then the minimum acceptable surface finish should be an Ra of around 0.35 to 0.45 microns and for competition engines I would imagine 0.25 would be more appropriate.

A honing grit of 400 would produce a typical Ra of between 0.5 and 0.6 microns hence the need for an 800 grit.

I wonder if the Goetze ring pack coatings supplied for use in an Alusil Cylinder differ from those used in a Nikasil cylinder as this may also have some impact.

I had a quick look in the Goetze Piston Ring Handbook but can't find enough detail.

http://korihandbook.federalmogul.com/en/index.htm

[bigred23]

I am currently going through a full rebuild on an '82 SC with 207k miles. I am considering as an option to have my Alusil cylinders replated through EBS. Was this experience with too-coarse honing an aberration? Does EBS now specify to Millenium that replated cylinder honing be done with a finer grit abrasive?

[VFR750]

Talk with Troy at ebs.

[SCadaddle]

Did the honing look like this? This is my plated set of Alusil cylinders that EBS prepared and provided the Goetze rings to run my original KS pistons. Still going strong virtually no oil use now for approximately 8500 miles.

[shoooo32]

I'm digging up an old thread as I think I might have a surface finish issue much like the OP. I used Millenium for cylinder re-plating, and now in the middle of engine assembly I stumble across this thread. Just for grins, I took the cylinders to work to check the finish. They average 14-17 RA, which seems excessive.

Now what do I do- send them back to be re-honed? Grape hone them into tolerance? I'm excited to get this motor together but I'd rather do it just once!

[SCadaddle]

Ha! I clicked on this thread tonight out of curiosity. After reading the first 5 posts, I thought about finding and posting the photos of my KS Alusil cylinders that EBS had plated for me back in 2012. Then I realized they were already here and this thread is 2 years old!

I can tell you guys this: The photos of my plated cylinders are exactly as EBS sent them to me. I used the original KS pistons and the Goetze ring pack that EBS also supplied. I'm guessing I'm a bit past 10,000 miles on my engine and it uses virtually no oil---maybe a quart of Brad Penn 20/50 in the timespan of a year when I change it. Figure a quart in 1500-2000 miles. Maybe I got lucky.

[shoooo32]

After consulting with Troy at EBS and Jeff Meyer at Millenium, both replied with the same answer. I'm paraphrasing, but it was roughly "The recipe hasn't changed, they're (15-17ra) and we've done cylinders for hundreds of motors without issue". Jeff also mentioned that they do have customers that ask for cylinders with a better surface finish (5-7ra), however they're race motors that are broken in on a dyno and sent to the customer ready to race.

I'm even more on the fence as what to do now!

[Mark Henry]

Not sure on LN's finish spec, but I do know they also use Millenium and the finish is way finer than in the pic above.
From LN/Millienium I've had 911 nikasil mahle's replated (Mahle pistons, Goetze rings), T4 and /6 air cooled Nickies (JE, forget ring brand but japanese) and 996 Nickies (JE, Wiseco rings) and the finish was all similar.
No break in issues but I'd say the Goatze took the longest fully seat.

[Mark Henry]

996 LN finish