Alusil - possible to replate ?
 

I've read a few threads but I'm still confused and would like to clear this:

Can an Alusil cilinder be replated ?

And do you know of where inside Europe can I find a trustable shop for this ?

We Nikasil plate used Alusil Liners quite routinely.

We always use Langcourt in the UK.

Home

And can I use the Alusil pistons with them ? I've read several opinions...

I just exchanged a few emails with someone from Langcourt that told me that alusil cilinders can't be replated... have to be scrapped.

Feedback please !

Yes it can be done. I had mine replated locally in the US by https://www.ebsracing.com/

Before:
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After:
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Yes, from several thread I understand that EBS can do it in the US.
I would just like to find someone in Europe, as sending to EBS would be too costly.

You may check before discounting it. I'm often shocked in how small the difference is at times and sometimes even quicker time wise if it goes by air rather than by truck. At least you'd get some answers and a reference point for other vendors. EBS is legit.

I bought some wheels from CA at $300 shipping. I bought wheels from Latvia at $400 and they arrived in 2 days (quicker).

Here's another good place in the US. They did the cylinders on my 72E.

PowerSeal USA

Who did you speak to?

We had some plated recently.

They have an office in Europe. I sent them an email.

Sam Welch.

He said they can only replate if the liners come off the cilinders.

I think there is a degree of misunderstanding and I spoke with Langcourt a few minutes ago.

Langcourt can and do plate individual Porsche 911 barrels made from Alusil.

There is no liner in a 1974 barrel/cylinder so you just send all 6 barrels and they will re-plate.

They cannot plate complete blocks such as 944 or 928 which have Alusil 'Liners' which is where, I believe the confusion has occurred.

I have just sent Langcourt a set of photograph to show the different barrel/cylinders and the details of the individual engines to try to help their knowledge base.

If you ship them to Langcourt with your contact details and send me a PM when they leave I would be happy to call them and make the relevant arrangements to ensure that the job gets done.

I am 100% condfident that the can be re-plated and that the work will be successful.

With regard to your pistons I do believe that you can run KS pistons for Alusil Cylinders in a Nikasil plated cylinder but you must use a compatible piston ring.

The KS ring pack is unsuitable for use with Nikasil.

The KS pistons, when new, were initially coated with iron and has a very thin layer of Tin on the surface to acts as boundary lubrication for break-in.

The iron prevents and galling taking place between the aluminium substrate and the piston and is vital to successful operation with alusil.

There are mixed views about the compatibility of an iron plated piston and Nikasil and it soemthing I have never tried.

From a metallurgy point of view the iron plated layer will be relatively soft at around 50 Rockwell B (This will depend on the composition of the coated layer) whilst 4032-T6 which is very similar to the alloy used by Mahle would be harder at 75 Rockwell.

It is possible that the iron coating may wear quickly but the thickness is around 13 microns so maybe this wouldn't be much of an siidue.

I am unaware of any tendency for adhesive wear to occur between Nikasil and iron and there are a number of reports where these pistons appear to have been used successfully in a Nikasil plated Alusil cylinder proving the correct rings are used.

Some concern has been expressed about relative expansion but as you will be using the piston/cylinder configuration that was supplied by Porsche I am not sure this is relevant.

In any case the expansion coefficients of 16% silicon/aluminium alloys are within 2-3% of 12% silicon alloys so I wouldn't be very concerned.

It is difficult to reach a good conclusion.

In 2012 I sent the KS Alusil pistons and cylinders from my 82SC, sporting about 154K miles, to EBS Racing in Reno to have the cylinders Nikasil plated, honed to match the KS pistons and EBS supplied the Goetze ring pack. I've gone past 10k miles on this engine with very little oil consumption, perhaps a quart of Brad Penn 20/50 in 2k miles, and it hasn't self destructed yet with regard to the piston/cylinder "mismatch". The iron plating of the pistons was still evident as the pistons would attract a refrigerator magnet.

prebordao...i would in your quest try this forum...in England .there are very knowledgeable peops there too;-)

Ivan

www.impactbumpers.com

L and N engineering is highly recommended.

Thx, I was forgetting them !

Hi, I had mine replated at Revaltec in France and they did a great job. These were 2.4 cylinders, so no alusil, but they also replate later engines.

good luck,
Dario

Yes, the confusion might have come from the 924/928 engines...

Do you have any idea on what the replating cost per cilinder might be ?

PS - have you heard of Motrac ? also in the UK