Cheshire Cat Posted 2July, 2018 Report Share Posted 2July, 2018 Hey gents, what place would you recomend to recoat (renikasil, resleeve etc) my alusil cylinders locally (in Australia I mean) Thanx in advance. Link to comment Share on other sites More sharing options...
ANF Posted 2July, 2018 Report Share Posted 2July, 2018 Alusil is not a coating, the whole cylinder block is made of Alusil (a mix of approx. 20% silicon and alloy)). As such no one can re-coat Alusil as it is not a coating. It can quite easily be bored and honed to a larger size, along with over size pitons. I have spent much researching along the path to rebuilding my Alusil 928 engine. Link to comment Share on other sites More sharing options...
AdRock Posted 2July, 2018 Report Share Posted 2July, 2018 Just curious, are you looking at re-coating them, just because they are alusil, or is there visibly something wrong with them? Link to comment Share on other sites More sharing options...
Cheshire Cat Posted 2July, 2018 Author Report Share Posted 2July, 2018 50 minutes ago, AdRock said: Just curious, are you looking at re-coating them, just because they are alusil, or is there visibly something wrong with them? To be honest I not sure. I was told they can't be used like they are thus my question. I can't see anything terrible with them. 1 hour ago, ANF said: Alusil is not a coating, the whole cylinder block is made of Alusil (a mix of approx. 20% silicon and alloy)). As such no one can re-coat Alusil as it is not a coating. It can quite easily be bored and honed to a larger size, along with over size pitons. I have spent much researching along the path to rebuilding my Alusil 928 engine. Now you got me confused like completely. In the book Wayne (from pelican parts, the author) states that it can't be reused. On pp forum as well as rennlist they say it can be honed, coated and reused. It's unclear to me in what condition one should or shouldn't coat/recoat Nikasil or Ausil and why Nikasil is better than Alusil? Link to comment Share on other sites More sharing options...
AdRock Posted 2July, 2018 Report Share Posted 2July, 2018 I've also been reading up about Alusil, as I believe when I get mine out they will also be the same. I did a leak down test over the weekend and all 6 cylinders checked out perfectly, so I'm going to reuse mine for sure. I'm going to remove them with the pistons and rings in place to save having to reinstall them. I have read on Pelican Parts forum that some people say they shouldn't be 're-ringed' because the new rings dont seat properly (apparently). Also that they can't be honed. But then other people say they have re-ringed them and not had any issues. I also did a google over the weekend over local places that do re-coating in Nikasil and there seems to be a few around... I'm not sure if that's an option for you or not if you don't want to re-use alusil. I gave up gave up researching once my cylinders checked out ok. Link to comment Share on other sites More sharing options...
ANF Posted 2July, 2018 Report Share Posted 2July, 2018 17 minutes ago, Cheshire Cat said: Now you got me confused like completely. In the book Wayne (from pelican parts, the author) states that it can't be reused. On pp forum as well as rennlist they say it can be honed, coated and reused. It's unclear to me in what condition one should or shouldn't coat/recoat Nikasil or Ausil and why Nikasil is better than Alusil? Ok, Nikasil and Alusil are completely different! From what I know about the 911 they used both. Nikasil is a coating on an alloy bore (think chrome plating - loosely explained), this cannot be repaired and has to be re-coated. Alusil is a 20% (+/-) mix of Silicon into the block/ cylinder material, it is very expensive to make but is very good, it generally will last a long time unless something damages it. Nikasil is cheaper and more commonly used - there has been some issues of late with this process I believe (of late I mean last 10 to 20 years....) Personally I think Alusil is better. It can be bored as per a steel engine and re-honed with the final step being Silicon lapping ("etching"). The problem with Alusil is that there is a lot of misinformation about on the internet, it took me months to find out the truth! PM me if you like I have lots of info. Cheers I am installing am Alusil liner into my engine, as the gouge in the bore is to deep to bore out. This alusil liner will then be bored and honed and lapped to suit my pistons. Find someone who knows what to do with an Alusil cylinder and you will be fine - don't believe all the internet BS! Link to comment Share on other sites More sharing options...
944s2cab Posted 2July, 2018 Report Share Posted 2July, 2018 Place in Artarmon NSW, called (confusingly) Balmain engineering did my 944 Alusil block Link to comment Share on other sites More sharing options...
Cheshire Cat Posted 2July, 2018 Author Report Share Posted 2July, 2018 33 minutes ago, AdRock said: I've also been reading up about Alusil, as I believe when I get mine out they will also be the same. I did a leak down test over the weekend and all 6 cylinders checked out perfectly, so I'm going to reuse mine for sure. I'm going to remove them with the pistons and rings in place to save having to reinstall them. I have read on Pelican Parts forum that some people say they shouldn't be 're-ringed' because the new rings dont seat properly (apparently). Also that they can't be honed. But then other people say they have re-ringed them and not had any issues. I also did a google over the weekend over local places that do re-coating in Nikasil and there seems to be a few around... I'm not sure if that's an option for you or not if you don't want to re-use alusil. I gave up gave up researching once my cylinders checked out ok. Who checked them if you don`t mind me asking? I have Alusil for sure and my compression test showed a compression from 75 to 100 with 90 in most of the cylinders. It was done on cold engine, when I`ve started searching found an info that it`s pretty ok to have this compression on completely cold engine. But that not the point, my pistons seems ok, cylinders too, I can`t see any bad signs however to cover myself up I`ve took one of the cylinders to Nick Cascone and he told me it wouldn`t be smart to use them as they are (plannig to out in there new set of JE or CP pistons same size). They have to be recoated (or just coated if they don`t have any coat at all according to Adam aka ANF) which I was quoted 2100 for the procedure. I think it`s a bit expensive. 35 minutes ago, ANF said: Ok, Nikasil and Alusil are completely different! From what I know about the 911 they used both. Nikasil is a coating on an alloy bore (think chrome plating - loosely explained), this cannot be repaired and has to be re-coated. Alusil is a 20% (+/-) mix of Silicon into the block/ cylinder material, it is very expensive to make but is very good, it generally will last a long time unless something damages it. Nikasil is cheaper and more commonly used - there has been some issues of late with this process I believe (of late I mean last 10 to 20 years....) Personally I think Alusil is better. It can be bored as per a steel engine and re-honed with the final step being Silicon lapping ("etching"). The problem with Alusil is that there is a lot of misinformation about on the internet, it took me months to find out the truth! PM me if you like I have lots of info. Cheers I am installing am Alusil liner into my engine, as the gouge in the bore is to deep to bore out. This alusil liner will then be bored and honed and lapped to suit my pistons. Find someone who knows what to do with an Alusil cylinder and you will be fine - don't believe all the internet BS! I know they are different but again, the book says Alusil is cheaper to make hense Porsche started using them on 3.0 etc. If we`ll put internet knowledge aside we have your opinion and a book`s one and they are opposite! 7 minutes ago, 944s2cab said: Place in Artarmon NSW, called (confusingly) Balmain engineering did my 944 Alusil block Thanx for the tip, will call them tomorrow! Link to comment Share on other sites More sharing options...
81SC Posted 2July, 2018 Report Share Posted 2July, 2018 This document from Kolbenschmidt (KS) should supply you with a few hours of reading & understanding. It goes into detail regarding your questions, click on the link below. https://www.electrosil.com.au/pdf/KS.pdf Link to comment Share on other sites More sharing options...
Peter M Posted 2July, 2018 Report Share Posted 2July, 2018 On 7/2/2018 at 5:41 PM, Cheshire Cat said: Nick Cascone and he told me it wouldn`t be smart to use them as they are (plannig to out in there new set of JE or CP pistons same size). They have to be recoated (or just coated if they don`t have any coat at all according to Adam aka ANF) which I was quoted 2100 for the procedure. I think it`s a bit expensive. Ah this is the nub of it me thinks! I suggest you purchase your pistons first and then send the whole lot off to the replater of your choice so they can get your clearances correct. I've recently had a set of 3.2 cylinders over-bored 3mm and re-Nikasil'ed There were only 2 suppliers of this service (reasonably) locally that seemed to have universal positive reviews that I could find: Electrosil and NZ Cylinders. NZ Cylinders ended up being $2,000 or $500 cheaper than Electrosil overall, including currency exchange and shipping. However Electrosil would have been much quicker so I sort of regret I didn't just send the cylinders to them. Link to comment Share on other sites More sharing options...
Cheshire Cat Posted 2July, 2018 Author Report Share Posted 2July, 2018 4 minutes ago, Peter M said: Ah this is the nub of it me thinks! I suggest you purchase your pistons first and then send the whole lot off to the replater of your choice so they can get your clearances correct. I've recently had a set of 3.2 cylinders over-bored 3mm and re-Nikasil'ed There were only 2 suppliers of this service (reasonably) locally that seemed to have universal positive reviews that I could find: Electrosil and NZ Cylinders. NZ Cylinders ended up being $2,000 or $500 cheaper than Electrosil overall, including currency exchange and shipping. However Electrosil would have been much quicker so I sort of regret I did just send the cylinders to them. Electrosil quoted me over the phone with 1850 for replating. But again, do I need to coat my alusil cylinders? Trying to read the manual posted by Brett right now... Need some time to absorb it in a proper way. Link to comment Share on other sites More sharing options...
Peter M Posted 2July, 2018 Report Share Posted 2July, 2018 My understanding is that you need to replate as the standard pistons in 911's are iron plated to prevent galling in the engines fitted with alusil cylinders. EDIT: This thread with some of the engine builders that actually know their stuff may answer your questions: http://forums.pelicanparts.com/911-engine-rebuilding-forum/854247-using-alusil-pistons-nikasil-cylinders.html Link to comment Share on other sites More sharing options...
tazzieman Posted 2July, 2018 Report Share Posted 2July, 2018 Why plate Alusil at all? They are honed and etched. At least on the 928. Link to comment Share on other sites More sharing options...
Cheshire Cat Posted 2July, 2018 Author Report Share Posted 2July, 2018 1 hour ago, tazzieman said: Why plate Alusil at all? They are honed and etched. At least on the 928. Good question haha :)) the more I dig the more it seems like I have to coat future pistons rather than cylinders. Link to comment Share on other sites More sharing options...
ANF Posted 2July, 2018 Report Share Posted 2July, 2018 6 minutes ago, Cheshire Cat said: Good question haha :)) the more I dig the more it seems like I have to coat future pistons rather than cylinders. Exactly Link to comment Share on other sites More sharing options...
Cheshire Cat Posted 2July, 2018 Author Report Share Posted 2July, 2018 Now it much clearer. Funny how none of the experts (neither Nick nor Stan from Performance 9) did mention I could use coated pistons instead of coated (yes, they are get coated too) cylinders. " Like materials attract. When rubbing two like materials together you get galling, even when lubricated. Especially soft materials. That's why the pistons are tin coated. In the racing world where you find a great deal of titanium, where two pieces of titanium work together you often find one or both pieces hard anodized. this prevents galling. Usually you find a titanium bolt with a steel nut. Same reason. In the case of Alusil or Reynolds Silacite (? spelling) a none coated piston will run fine until you shut the engine off. When the movement stops, the aluminum sticks. I'm have tried thin dense chrome (.0004) in place of tin but the chrome seemed to retain the heat and the piston growth was unacceptable. The guys at Techline lubricants swear there dry film molly will prevent galling but building these engines takes too much work to try to save a buck with reusing alusil cylinders. If you must reuse Alusil cylinders have them Nicasiled. The Silacite plates better than stock Nicasil and the result is like new cylinders. If your stock pistons are still in good shape you can have the replated cylinders honed to match. __________________ Henry SchmidtSUPERTEC PERFORMANCE" Link to comment Share on other sites More sharing options...
Cheshire Cat Posted 2July, 2018 Author Report Share Posted 2July, 2018 The response from CP Carrillo. A bit cheaper than cylinders coating don't you think? We do offer poly dyn coating that which is a special coating for alusil bores. Its an outside process we use and takes about 2 weeks. Cost is $45 per piston. Link to comment Share on other sites More sharing options...
ANF Posted 2July, 2018 Report Share Posted 2July, 2018 Wossner and Arias offer forged pistons with a suitable coating. SPS pistons in Melbourne will make you pistons and HPC can coat them for $27.50 each to suit Alusil. I believe one of the best options is to buy some new Mahle Porsche pistons with the original coating already on them. I found new Mahle pistons available for my 928 and in my searches found that there are many more parts available for 911s..... For anyone suggesting to "recoat" an Alusil bore they simply do not understand what Alsuil is..... this in from my 928 Porsche Factory workshop manual (they should know what to do!). The piston and rings run in the Silicon particles giving a perfect low friction surface. Link to comment Share on other sites More sharing options...
tazzieman Posted 2July, 2018 Report Share Posted 2July, 2018 Someone should write a flowchart of the options/prices as this info will help others in the future . Link to comment Share on other sites More sharing options...
ANF Posted 2July, 2018 Report Share Posted 2July, 2018 4 minutes ago, tazzieman said: Someone should write a flowchart of the options/prices as this info will help others in the future . There are such variable prices out there this would be difficult, but a good idea. I got 4 new Mahle pistons for $95 US each, was quoted $900 for one (Australia), can get a complete set of second oversize ones for $1200 (Europe) and had prices for new custom made pistons (with coatings) varying from $2500 up to almost $4000 (Aust and US) - of course this is for 8 x pistons. The boring/ honing part should only be slightly more than a regular cylinder (additional cost of the felt pads for the Silicon lapping $150 +/-). Unfortunately from what I have learnt the 911 over the years used both Alusil and Nikasil which is what leads to a lot of the confusion..... and newer engines (M96 and Cayenne) use Alusil again (M96 has Alusil liners with regular alloy cast around them to form the block) Just some more random info..... "The Alusil aluminium alloy is commonly used to make linerless aluminium alloy engine blocks.[4] Alusil, when etched, will expose a very hard silicon precipitate. The silicon surface is porous enough to hold oil, and is an excellent bearing surface. BMW switched from Nikasil-coated cylinder walls to Alusil in 1996 to eliminate the corrosion problems caused through the use of petrol/gasoline containing sulfur." Link to comment Share on other sites More sharing options...
AdRock Posted 3July, 2018 Report Share Posted 3July, 2018 16 hours ago, Cheshire Cat said: Who checked them if you don`t mind me asking? The Leak down test? I did that myself. :) Mine was also done on a cold engine, as the engine is out of the car. But since I've never really heard the engine run, I just wanted to confirm that the rings and the valves were seating properly. Link to comment Share on other sites More sharing options...
Cheshire Cat Posted 3July, 2018 Author Report Share Posted 3July, 2018 2 hours ago, tazzieman said: Someone should write a flowchart of the options/prices as this info will help others in the future . That might be me, was just thinking about it while drive to work. Link to comment Share on other sites More sharing options...
Cheshire Cat Posted 3July, 2018 Author Report Share Posted 3July, 2018 1 hour ago, AdRock said: The Leak down test? I did that myself. Mine was also done on a cold engine, as the engine is out of the car. But since I've never really heard the engine run, I just wanted to confirm that the rings and the valves were seating properly. Nah, I assumed that :)) did you show the cylinders to someone else or you made your decision based on the test only? now my problem consists of figuring what should I do with cylinders, just hone them, etch or can use what they are. Tend to think that experts might convince me to do something cos of money... or I'm a bit paranoid Link to comment Share on other sites More sharing options...
AdRock Posted 3July, 2018 Report Share Posted 3July, 2018 9 minutes ago, Cheshire Cat said: did you show the cylinders to someone else or you made your decision based on the test only? I'm yet to pull my cylinders out of the engine, but based on the test, I'm fairly sure I will reuse them, unless I see something shocking when I remove them. I'm only removing my engine because of the broken head studs, so I'm only looking to repair what's broken or obviously needs replacing. I normally drive a Kombi, so simply driving a stock 911 will be at least a 100hp upgrade! :P Link to comment Share on other sites More sharing options...
ANF Posted 3July, 2018 Report Share Posted 3July, 2018 Measure your bore and piston, check it against the factory tolerances and wear limits, chances are high that you will still be within them. Mine are except of course for the damaged one and all will be re-used (I am only putting some new pistons in as they came as a package deal). You do not need to spend a fortune to fix a Porsche! Link to comment Share on other sites More sharing options...
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