Experience with Alusil cylinder repair shops

[ProjektAutoScott]

I have a block with low compression and minor scoring in a cylinder due to an injector that was washing oil from the walls. No other catastrophic failure, or damage. Does anyone have recent experience with Millennium Technologies, e-megatronic, or any other machine shop capable of repairing Alusil bores?

Please post any Alusil machine shop recommendations you may have here, so far lots of companies in the country claim it will be “no problem”, but I am looking for the real deal, experienced shop who knows S65s. No interest in stroker or iron sleeved builds, no interest in used engines unless a forum member has a nice block.

My car is a higher milage e90, this is only about repairing this block to an acceptable condition. If I wanted absolute perfection, I’d buy a new short-block from BMW. Please know I understand the concerns from many members over attempting to repair these blocks.

Thanks in advance, I will likely be going with one of these shops, and I will post my experience publicly here for future reference.

[amrazM]

Millennium Technologies in Wisconsin. Alusil is tricky and very few shops can do it properly which is why some people are still sleeving these blocks.

[SYT_Shadow]

Have you tried contacting Carbahn, Steve Dinan's shop? They have the most experience in Alusil in the US.
I've never heard of them repairing a block but it's worth the conversation

[alfalfa]

It is possible to get this done with an Alusil sleeve on this 1 cylinder.
Find a shop which have a lot experience doing this is the hardest part cause this is no standard repair job.
When the shop recommends sleeving all 4 cylinders in this bank it's a good shop. Cause sleeving just this single one will introduce stress into the block and have influences on the bore next to it. For just having a running engine at low costs sleeving just one cylinder will do it.

Did you checked the piston skirt? I would suggest the piston will also have scratches and you need a new one for running in the alusil sleeved cylinder.

[DukeofAlexandria]

Did you figure out WHY the injector was washing the cylinder? Was it stuck open, fuel injector malfunction?

-Duke

[ProjektAutoScott]

Thanks all

Originally Posted by DukeofAlexandria

Did you figure out WHY the injector was washing the cylinder? Was it stuck open, fuel injector malfunction?

-Duke

Leaking. Going in the trash, already have a set of 8 new ones.

[ProjektAutoScott]

Update: after calling around, the only thing that is "no problem" is finding shops who immediately jump to boring and iron-sleeving the entire block. Millennium tech promptly quoted me to iron sleeve the block, without even asking or seeing the condition of the cylinder in question. CarBahn (Steve Dinan) didn't answer. Lang Racing in California are the only ones so far who understand, and think they know a shop that can do what I am asking, but were only willing to facilitate the process, rather than directly revealing the name of the machine facility. Understandable, they are a business, however I don't feel like working with a middle man if it can be avoided.

Alusil is just a type of aluminum with silicone content through-out. It can be machined just like any traditional block, and only requires special honing at the end to reveal silicone crystals for the piston ring to ride on. For reference, the procedure I am looking for is absolutely possible, and reasonable based on technical articles like this one: https://cdn2.ms-motorservice.com/fil...ocks_51708.pdf it's also possible to have single, 3mm wall Alusil sleeves installed to retain factory bore size and pistons. Meaning you could effectively repair the countless "bad" blocks out there with damage to one or two cylinders. This service would be absolutely indispensable, and cost effective for the s65/s85 owners.

Strange on how hard it is to find info considering all of the Audi and Porsche guys who have been dealing with this since the 80s. Worst case, Mahle even offers factory +0.20mm oversized pistons coated for Alusil bores on S65/85s BMW part 11257840920. Just trying to find a shop that can cut and hone the Alusil cylinders properly. Or even better, and a long shot in the US is a shop who will install one Alusil sleeve. It seems to be a very reasonable service to ask for in Europe, with Kolbenschmidt (creators of Alusil) themselves even offering the services and Alusil sleeves for all makes.

Anyway, if you've made it this far: lmk, thanks.

[amrazM]

Originally Posted by ProjektAutoScott

Update: after calling around, the only thing that is "no problem" is finding shops who immediately jump to boring and iron-sleeving the entire block. Millennium tech promptly quoted me to iron sleeve the block, without even asking or seeing the condition of the cylinder in question. CarBahn (Steve Dinan) didn't answer. Lang Racing in California are the only ones so far who understand, and think they know a shop that can do what I am asking, but were only willing to facilitate the process, rather than directly revealing the name of the machine facility. Understandable, they are a business, however I don't feel like working with a middle man if it can be avoided.

Alusil is just a type of aluminum with silicone content through-out. It can be machined just like any traditional block, and only requires special honing at the end to reveal silicone crystals for the piston ring to ride on. For reference, the procedure I am looking for is absolutely possible, and reasonable based on technical articles like this one: https://cdn2.ms-motorservice.com/fil...ocks_51708.pdf it's also possible to have single, 3mm wall Alusil sleeves installed to retain factory bore size and pistons. Meaning you could effectively repair the countless "bad" blocks out there with damage to one or two cylinders. This service would be absolutely indispensable, and cost effective for the s65/s85 owners.

Strange on how hard it is to find info considering all of the Audi and Porsche guys who have been dealing with this since the 80s. Worst case, Mahle even offers factory +0.20mm oversized pistons coated for Alusil bores on S65/85s BMW part 11257840920. Just trying to find a shop that can cut and hone the Alusil cylinders properly. Or even better, and a long shot in the US is a shop who will install one Alusil sleeve. It seems to be a very reasonable service to ask for in Europe, with Kolbenschmidt (creators of Alusil) themselves even offering the services and Alusil sleeves for all makes.

Anyway, if you've made it this far: lmk, thanks.

maybe reach out to some 944 guys. Im assuming MT isnt willing to bore and hone alusil at this point.

[ProjektAutoScott]

Originally Posted by amrazM

maybe reach out to some 944 guys. Im assuming MT isnt willing to bore and hone alusil at this point.

Good call. Basically the oldschool 944 idea is to buy this gear to hone the cylinders yourself https://goodson.com/products/an-30-silicon-compound

Based on the articles I can find about Alusil, it seems you can finish the cylinder walls on your own with the right hone and compound, and people have/do. You wouldn't be able to verify proper surface roughness without a $4,000 Profilometer, this step is really crucial to verify you have relieved enough aluminum to properly expose the silicone crystals. The way people get around that issue is by honing the cylinder for quite a while. Found some AMG guys with similar ideas. Cool to try if I was messing around with re-ringing used blocks, or refreshing a high mileage engine. The honing process will only remove extremely small defects and scoring, so I'll keep looking for shops

Interesting stuff regardless

[rcracin]

I've seen lots of damaged blocks bored out. Usually to 94mm for stroker builds.

I wouldn't mess with replacing a sleeve. Rather, get the overbore pistons you referenced. Carbahn usually responds so I'd try them again. I believe they have the most successful track record in working with bmw alusil blocks.

[ProjektAutoScott]

Originally Posted by rcracin

I've seen lots of damaged blocks bored out. Usually to 94mm for stroker builds.

I wouldn't mess with replacing a sleeve. Rather, get the overbore pistons you referenced. Carbahn usually responds so I'd try them again. I believe they have the most successful track record in working with bmw alusil blocks.

I respect that opinion, but it goes against the purpose of what I am inquiring about. CarBahn wants some serious $$$ to go overbore, couldn't get much more info after calling in again. Currently waiting to hear back from them on options

Again, not looking for perfection here on this old block. Replacing one cylinder with the proper Alusil sleeve is acceptable according to Kolbenschmidt, said sleeve would have the same alusil honed finish as the rest of the cylinders. This would also mean I can retain the factory pistons, and have the other 7 cylinders honed along with the new Alusil sleeve.

After speaking with Millenium Tech again today, they admitted they could do it, and they have the sleeves and equipment but won't do one cylinder. The reasoning I was giving by the first rep was that they aren't set up to price out a single cylinder sleeve of alusil on a v8, and the second rep basically said it's not worth it to them, and would only do 4 cylinders minimum at $4700.

Mind you, this is for alusil sleeves, not iron, not plating, just alusil. Meaning they are willing to chop up 3 good cylinders, compromising the block further, and fill them with liners of the same Alusil material. When asking the first rep about that, he said even if they just do one cylinder (which they can) they will still charge for half a bank. I am sure they do fantastic work, but it seems the automotive side of the shop isn't interested in smaller jobs. Fair enough

Anyway, good news: I found a competent shop in California who will do the work. Great reviews, and a great price. I will send them my block, and if it goes well I will update this thread with their name, and contact info. So far they were very confident in their knowledge of the material, and all of the correct equipment to repair the single cylinder, while honing the other 7 to effectively create a "fresh" engine with matched pistons and new rings.

[rcracin]

Part of the issue with taking a risk such as this is the sunk cost of gaskets and bolts in a rebuild. Then potential damage to heads if something goes wrong. This is assuming you’re rebuilding 100k mile heads.

You’ll be around $4k into this build with repaired sleeve. Plus the time and effort swapping.

It’s quite an undertaking when compared to what’s tried and true.

[ProjektAutoScott]

Originally Posted by rcracin

Part of the issue with taking a risk such as this is the sunk cost of gaskets and bolts in a rebuild. Then potential damage to heads if something goes wrong. This is assuming you’re rebuilding 100k mile heads.

You’ll be around $4k into this build with repaired sleeve. Plus the time and effort swapping.

It’s quite an undertaking when compared to what’s tried and true.

It's all risky man. Not too worried about it, but I appreciate the input!

[alfalfa]

As I stated above doing all cylinders on one bank means they know what they are doing.
If you just sleeve one cylinder you will impact the bore of the next one. Look at the small wall between the cylinders and now imagine you will overbore this and put a sleeve in there. Alusil is a weak material in the end and not comparable with a iron cast block.

[ProjektAutoScott]

Originally Posted by alfalfa

As I stated above doing all cylinders on one bank means they know what they are doing.
If you just sleeve one cylinder you will impact the bore of the next one. Look at the small wall between the cylinders and now imagine you will overbore this and put a sleeve in there. Alusil is a weak material in the end and not comparable with a iron cast block.

As stated above, that argument only applies to an iron sleeving process. What we are talking about is cutting a hole in aluminum and sleeving it wil the same aluminum, in the form of an aluminum sleeve. I would never ask for a single sleeve of different material, that would in fact compromise the block. The other shops I’ve spoken to today have confirmed a single aluminum sleeve would be the least invasive process.

Please read page 30 of the PDF I linked above from one of BMWs main suppliers if you aren’t understanding the procedure I am having done to my 8th cylinder

[alfalfa]

I absolutely know what you are talking about and I know the document.
I had the same issue when 2 blocks for my stroker engine where damaged. So I had many options for going on. On was the Alusil sleeve which I didn't used in the end. My engine shop which has a high reputation here offers it but doesn't recommend just doing one cylinder on this engine.
How does the Alusil sleeve will hold in place? There is no difference how to insert a iron or alusil sleeve. Cause the sleeve has to be bigger than the bore. The block is heaten up and the sleeve is cooled down.
Kolbenschmidt just say that there is an option to rebuild one cylinder like this and they have the spare parts. They do not recommend this and the don't care about the small wall between the bores. That is always the knowledge of the engine shops what works and what not. In other engines with thick walls I would agree there would almost be no issue when just sleeving one cylinder.

[Johal E32]

You could try reaching out to some of the old school BMW engine builders such as Korman Autoworks or Metric Mechanic.


https://kormanautoworks.com/rebuilding.htm

https://metricmechanic.com/engines/

[ProjektAutoScott]

Originally Posted by alfalfa

I absolutely know what you are talking about and I know the document.
I had the same issue when 2 blocks for my stroker engine where damaged. So I had many options for going on. On was the Alusil sleeve which I didn't used in the end. My engine shop which has a high reputation here offers it but doesn't recommend just doing one cylinder on this engine.
How does the Alusil sleeve will hold in place? There is no difference how to insert a iron or alusil sleeve. Cause the sleeve has to be bigger than the bore. The block is heaten up and the sleeve is cooled down.
Kolbenschmidt just say that there is an option to rebuild one cylinder like this and they have the spare parts. They do not recommend this and the don't care about the small wall between the bores. That is always the knowledge of the engine shops what works and what not. In other engines with thick walls I would agree there would almost be no issue when just sleeving one cylinder.

I’m glad you were able to find something that worked for you, again I’m really not interested in going back and forth over the opinions/options of individuals here on the forums. I’m interested in those who’ve done it, or are interesting in doing it. Not those who decided it wasn’t for them. I’ve considered the risk, researched, and consulted. The process for sleeving a single cylinder with very little material between cylinders is outlined, whether you agree with it or not. The shop I am working with has quite the portfolio. Porsche, BMW, Benz, Audi, marine and automotive racing engines, and a very good understanding of alusil blocks and the required processes and tooling. Like I said, if it works out I’ll drop their info in this thread after I have put some miles on the car.

Thanks for the input

[ProjektAutoScott]

Originally Posted by m3reid

Holy shit dude. I have a 2008 E92 M3 with 98k miles on it, brought it in to have VC gasket warrantied and to investigate a misfire issue....cylinder 8 was at 54 psi

Turns out injector 8 was stuck open and oil washing cylinder wall. Engine still runs and idles. Currently debating the Carbahn 4.2L stroker build or just selling it for $10k and shooting myself. Cheers to shitty luck mate. What did you end up doing?

Must be said, obviously run it anymore unless you want to risk hydrolocking! Replace the injectors for $14 a piece with Bosch OEM, if you haven’t already. If your rotating assembly is OK, you’ll fair much better than many.

I’ll buy it right now for $10K if you are serious lol! I’ll gladly buy another M3. I now have a 2011 e93 that I am loving. The 2009 e90 engine is awaiting the machining. I am attempting to save the block, and work with a shop that knows Alusil well/was willing to work on the bad cylinder. An iron sleeved build is not in the cards for this car and I disagree with many on the forum who believe that is the only option. I just want the car to run somewhat smoothly again, with stock internals. Willing to be a guinea pig here, I do all of my own labor anyway. If it doesn’t work, I’ll get a new block. I plan to update the thread with the named shop in a few months or so when the car is back together and has been running for some time.

If you rely on the car, and you are paying for the work to be done, I can see why it would make sense to just go big and have CarBahn do the job. If you want to sell your car, seriously PM me your price.

[Drifter2090]

Any updates on the E90 OP?

[herrubermensch]

Originally Posted by ProjektAutoScott

I have a block with low compression and minor scoring in a cylinder due to an injector that was washing oil from the walls. No other catastrophic failure, or damage. Does anyone have recent experience with Millennium Technologies, e-megatronic, or any other machine shop capable of repairing Alusil bores?

Please post any Alusil machine shop recommendations you may have here, so far lots of companies in the country claim it will be “no problem”, but I am looking for the real deal, experienced shop who knows S65s. No interest in stroker or iron sleeved builds, no interest in used engines unless a forum member has a nice block.

My car is a higher milage e90, this is only about repairing this block to an acceptable condition. If I wanted absolute perfection, I’d buy a new short-block from BMW. Please know I understand the concerns from many members over attempting to repair these blocks.

Thanks in advance, I will likely be going with one of these shops, and I will post my experience publicly here for future reference.

Old thread, I know, but we consider ourselves one of the top alusil bore reconditioning shops (out of a whopping three or four in the nation). At Partee Racing, the alusil engines we build are BMW S62s, S65s and S85s. We have spent quite a bit of money and time developing our specific recipe for boring, honing and re-exposing the silicone of alusil bores.

The re-exposure process is done with a manual hone and requires specific friction levels (as measured by the amps pulled by the machine while honing) for a specific amount of time to achieve the necessary surface roughness parameters (Ra, Rpk, Rvk, Mr1 and Mr2) as confirmed on a cylinder by cylinder basis with a profilometer. One of our former colleagues (now a consultant to us) is the former head of Dinan's engine shop during the time when it supplied the Rolex 24 Hour winning S62 engines.

Interestingly, BMW recently restarted production of new S62 blocks, and one that we ordered arrived with some damage that precluded its use. So we have used that block as a test mule to compare it with our own work. The cylinder surface roughness parameters were acceptable, but nowhere near ideal nor what we achieve through our process. As an aside, note, we discovered that BMW does NOT use torque plates when it bores and hones alusil cylinders, meaning that those cylinders are materially distorted out of round once cylinder heads are bolted into place. Not out of spec, but enough to be material to a high performance engine in our opinion. As a result, we re-bore, re-hone, and re-expose even brand new blocks from BMW. And we use torque plates on both banks simultaneously!

I love this stuff and am happy to discuss it with anyone who so desires. peters@parteeracing.com is my email.

--Peter

[JellyStyle]

Originally Posted by herrubermensch

Old thread, I know, but we consider ourselves one of the top alusil bore reconditioning shops (out of a whopping three or four in the nation). At Partee Racing, the alusil engines we build are BMW S62s, S65s and S85s. We have spent quite a bit of money and time developing our specific recipe for boring, honing and re-exposing the silicone of alusil bores.

The re-exposure process is done with a manual hone and requires specific friction levels (as measured by the amps pulled by the machine while honing) for a specific amount of time to achieve the necessary surface roughness parameters (Ra, Rpk, Rvk, Mr1 and Mr2) as confirmed on a cylinder by cylinder basis with a profilometer. One of our former colleagues (now a consultant to us) is the former head of Dinan's engine shop during the time when it supplied the Rolex 24 Hour winning S62 engines.

Interestingly, BMW recently restarted production of new S62 blocks, and one that we ordered arrived with some damage that precluded its use. So we have used that block as a test mule to compare it with our own work. The cylinder surface roughness parameters were acceptable, but nowhere near ideal nor what we achieve through our process. As an aside, note, we discovered that BMW does NOT use torque plates when it bores and hones alusil cylinders, meaning that those cylinders are materially distorted out of round once cylinder heads are bolted into place. Not out of spec, but enough to be material to a high performance engine in our opinion. As a result, we re-bore, re-hone, and re-expose even brand new blocks from BMW. And we use torque plates on both banks simultaneously!

I love this stuff and am happy to discuss it with anyone who so desires. peters@parteeracing.com is my email.

--Peter

Finally find someone that knows Alusil, will reach out to you Peter. Have a S63B44 build for a forged motor for X5M.. Why the heck does BMW sell 89.25mm pistons if someone cant bore Alusil? ha

joe