Kolbenschmidt or Mahle Test?

MOMO3.2 · 12-04-2006, 08:05 PM

Is there a way to establish whether a 3.2 motor has either Kolbenschmidt or Mahle cylinders without dissasembling anything?

Thank you.

Mike

mb911 · mb911's Garage

typical rule of thumb is 10 fins is KS , 11 fins is Mahle Now I am sure there is probably someone out there can tell you more

WydRyd · 12-05-2006, 01:12 PM

Isn't there a KS or Mahle imprint on the outside of the cylinder?

Lukesportsman · 12-05-2006, 03:19 PM

The is the best I could do in the shop a few minutes ago. The first are from a Mahl. The last are from a 3.0 assembled with KS.

Now if I do this right, these should be the KS:

There were several small numbers like part numbers or so on the bottom of the KS near block.

MOMO3.2 · 12-05-2006, 04:24 PM

Thank you all. I will check this weekend. I hope, I hope, I hope I have Mahle's...

Mike

tctnd · 12-05-2006, 04:36 PM

Mike,
The nikasil plating in the Mahle cylinders is slightly magnetic while the inside of the KB is not. If you remove a plug and rotate the crank til that piston is near BDC you can "feel" the cyl wall with a small magnetic probe and determine which type you have.
regards,
Phil

MOMO3.2 · 12-05-2006, 04:54 PM

Thank you Phil. I may try that with a really, REALLY secure mechanic's magnet.

I did look under the car just now and was able to count 11 fins. There were no markings on the bottoms of the barrels.

I am not looking at a rebuild any time soon (fingers crossed and knocking on wood). I would just like to know what I do have so I can plan for work way, WAY down the road.

Mike

cstreit · cstreit's Garage

KS also have a much more reflective outer surfance than Mahle. Once you've seen both together, they are hard to confuse...

Ken911 · 12-06-2006, 05:14 PM

whats wrong with the ks cylinders are they not reusable like the mahles?

Walt Fricke · 12-06-2006, 07:37 PM

I believe that all Kolbenschmidt 3.0s are Alusil. I am not sure that all Mahles are Nikasil, however. My understanding (which could easily be wrong) is that Mahle also made Alusils for Porsche. And maybe KS made some Nikasils, all just to confuse us.

Which is why you have to do the magnet test no matter what. Nothing to it if you have the heads off. I hadn't thought of the thin magnet test, but that seems a great idea (tricky to do with engine in car? That plug hole is way down in there as it is).

There is much debate (do a search of old forum topics) about how, or even if, you can successfully re-ring an Alsusil setup.

There seems to be no debate about Nikasils - they can be re-ringed if they are still within spec and not gouged or otherwise damaged. Whether or how to prepare them for re-ringing has also generated some spirited discussion.

Walt Fricke

Ken911 · 12-07-2006, 02:02 AM

the ones on my turbo I used the dishwasher then red scrubbie and soap and water method dont have it running yet though.

Lukesportsman · 12-07-2006, 05:59 PM

Yes Chris, I was hoping the photos showed that a little.

WydRyd · 12-07-2006, 07:13 PM

I have a set of 95mm cylinders, which are definitely magnetic inside. They must be Nikasils, right? I'm selling them anyway, so no big deal to me.

cstreit · cstreit's Garage

Quote:

Originally posted by Lukesportsman
Yes Chris, I was hoping the photos showed that a little.

Well the two lower photo's definitely look like KS, but cameras sometimes mis-represent. (look at Britney Spears photos... )

tech 1 · 12-13-2006, 05:35 PM

alusils can be converted nikasil.I'm having a set K/S alusils converted to nikisil as I type.So......I'm pretty sure the magnet test is the only for sure method! Tim

Walt Fricke · 12-13-2006, 05:53 PM

Right - the magnet is the only sure way.

But the chance of happening upon a Nikasiled set of Alusils is pretty remote, wouldn't you think? At least without the seller knowing of it and using that as a price booster? When you get done with the Nikasiling (including the extra cost of machining over just re-Nikasiling), and coming up with Nikasil compatible pistons (i.e., not the old ones from Alusil days), and new rings, might you not be pushing the cost of a new set of Nikasil Ps and Cs?

Unless, like me, you are building a race motor and stock Ps won't do.

Walt Fricke

tech 1 · 12-13-2006, 06:15 PM

Hey Walt,It is a race motor, however the total price,cylinders nikasiled, J E pistons, Goetze rings was less than $2000.00 so that considered it's pretty close price wise.Tim.

criv911 · 12-13-2006, 06:39 PM

tech 1, Are you using US chrome in Wisconsin where are you buying the JE's from, and what are the specs for the pistons and cylinders I am contemplating the same route 10.5 cr and 98mm bore. I haven't found prices that low though.

tech 1 · 12-13-2006, 09:32 PM

Yes I'm using US Chrome.I think that there are only a couple of places in th U.S. that do that process. We are a jobber for JE so I'm buyimg them direct.As far as the specs go.........are we that good of friends?This IS one of our race motors.I can tell you this though if this is a C.I.S. engine then you must use the Slant Dome piston. J E can provide that for you in 10.5:1.So actually my specs wouldn't help you. This engine needs a 95mm bore to be legal for his particular class,and must retain the cis injection.If you are using carbs. or MFI You would want to go with a different dome shape.When you order custom JE's they should furnish you with an engineering sheet, and YOU must spec out your piston! I think any JE distributor can provide you with that.If not I think you can find it on thier website and print it up. Hope that helps.Tim. ps U.S. chrome needs your piston or pistons,if they are not exactly the same,before final hone.The JE skirt to cyl. wall is pretty close for an air cooled engine.I believe that the current recomended clearance is .0015".

Walt Fricke · 12-13-2006, 10:50 PM

Yes, 0.0015 is what J&E recommends. Pretty amazing. Hope it works. I'm stalling around on sending my old 95mm Alusils, which I kept for what then was no particular reason, to US Chrome with a sample of my J&Es.

Walt