3.0sc Re-ring advice
 

Guys,

I'm addressing broken head studs that were discovered when my car was PPI's by a prospective purchaser.

Engine oil use is not excessive by any means and engine compression is good apart from teh cylinder with the broken head stud.

It was my intention to change the rings (114,000 miles) while we are there.

I have the KS pistons. I was told that putting in new rings would take a long time to bed-inn because of the alusil liners.

Am I wasting my time?

Many thanks

Jim

There is a thread that Wayne wrote in reguards to Alusil liners, the bottom line was that they can't be re-ringed. I did however get a very positive responce from Charles @ LNengineering that was about the possibility of replating the alusil cylinder with Nikasil or Ni-com so it could be re-ringed I am currently trying this idea as I just sent a set out. I will get back to you with the results in the mean time give Charles a call

Any idea on the cost of replating alusil cyls?

I've also successfully machined the tops of the ce-grooved to a step on the tops of the cylinders to take a copper gasket which then also allows the cylinder to be taken out to 98mm. Cost is roughly the cost of a set of QSC cylinders, but then at least you are starting with a nice German casting and the same plating we use on the Nickies cylinders we manufacture.

I've personally re-ringed one set of Alusils and re-used the old rings on 3 other race engines. Had no problem with any of them. Your mileage is not excessive. I'd measure your ring land clearance and ring end gaps to see if you can or should re-ring. I will probably stay with Alusil from now on because of the price.

-Andy

I read that Superman on this board re-ringed his alusils without problem. John Walker knows that car very well and speaks very highly of the engine. But I have also read that that is a bit risky.

What do you tell the 944 and 928 guys? Throw away your block because it's Alusil. I think the Alusil cylinders get a bad rap. An engine builder whose bread and butter and is putting his name on the line might not want to gamble on Alusil,... it depends on your level of expertise, financial status and if you are willing to take the cance on new rings or reuse the old ones.

Sorry, I just had to give a differing view. I have had good luck reringing Alusil 944 motors, not 911 cylinders, so take it for what its worth.

Re-ring Alusil
 

I re-ringed my Alusil cylinders on my 3.2 with great success. My mechanic, with 20 plus years of experience building Porsche engines, says he has done it many times without problems. This is assuming the cylinders and piston are in-spec.
Mark

Thanks to all for the replies.

regards

Jim

I have also done it two different times on a 3 litres, with fairly good results.. The latter of the two let out a littlle larger belch of smoke upon startup than I liked, but oil consumption seemed to be normal. I think that the general consensus is that it is a crapshoot. If if is your own motor, I guess all that you loose is your time, and a gasket set, if it does not work. Good luck .
Fred

That's what happened to me when I did it after about 4000 miles. Oil usage is minimal, hardly ever have to top up between oil changes,but the start up smoke is a pain in the ......

I too re-ringed my 3.0 Alusil cylinders and they have performed well with minimal oi consumption.
Rick

If one does re-ring the pistons using the KS cylinders, would you use the stock rings? And would that be the standard ring sets sold her by our host or the rings JE Pistons sells?
Would like to know thoughts about this.
Thanks.

I use stock Goetz rings. I know they are available at EBS, but are probably available at Pelican. They seem to be the same rings for Alusil and Nickasil.

-Andy

Thanks, Andy. Sounds as if you have had good luck with the Alusil cylinders too. I am thinking about a purchase for a 3.0 so I'm on the fence right now with the decision.

If you are interested in a really good read on Alusils and re-ringing. Check out this link. It goes on forever but there is a lot of good information.

I used the Goetz rings as well.
Rick


http://forums.pelicanparts.com/911-engine-rebuilding-forum/137346-re-ring-alusils.html?highlight=alusil

Thanks, Rick...I will start reading that thread.
:D