[TAOSSTI]

Has anyone heard of Cosworth sleeves failing? About to put motor together and heard this nasty rumor last night. May not be true but I wanted to check.

Thanks!

[jays05]

Originally Posted by TAOSSTI

Has anyone heard of Cosworth sleeves failing? About to put motor together and heard this nasty rumor last night. May not be true but I wanted to check.

Thanks!

I thought Cosworth didn't sell sleeved motors anymore?

FWIW, I stayed with the stock cylinder liners on my build. I did some searches and found more people with dropped sleeves than I could find with cracked oem liners....

[CrawfordPerformance.com]

If you push the motor hard enough, anyone’s aftermarket sleeves will be pushed down into the aluminum block. Another thing to think about is the expansion rate of the iron liner compared to the aluminum block, the hotter the motor gets the lower the iron liner will be in relation to the deck of the aluminum block. It’s well worth the cost / hassle on a race motor that will be rebuilt on a regular basis but a sleeved aluminum block motor has no place in a daily driven street car.

In time the Subaru engine builders will discontinue sleeving their motors for street use.

Good luck with your project

[Darton Sleeves]

We have never had a single sleeve sink in the EJ25 blocks that we have installed. We have easily sold more than 100 sets of the EJ25 sleeves without an issue. Should there be a failure 99% of the time it is due to improper machining and installation of the sleeve. For street use easily the majority of the sleeves we sell are being used on daily street driven vehicles.

[Neanderthal Racing]

question for darton: i heard from a builder that some sleeves have been slipping as a result of manufacturers using an epoxy or or cement that can melt at higher temps. any truth to that?

[srt42sti]

not to mention shimming them up in a block with aluminum filler (ala aluminum can) when the block is botched due to a cutter slipping

[Neanderthal Racing]

sounds like there's a story there.

[Darton Sleeves]

Originally Posted by Neanderthal Racing

question for darton: i heard from a builder that some sleeves have been slipping as a result of manufacturers using an epoxy or or cement that can melt at higher temps. any truth to that?

Depending on the manufacturers sleeve design they may have to rely on cement or epoxy which will cause issues. Temperature issues will depend on the type of cement or epoxy used. The main problem with using cement or epoxy is that they are too hard or if there is any movement with the sleeve it will turn to dust. If there is any movement due to expansion the cement or epoxy will crack.

We supply and use 518 Loctite with all of our MID and Seal Tight sleeves we supply. The 518 is good up to 300 degrees and remains flexible. We also use o-rings to seal the sleeves so sealer in not necessary on the bottom of the sleeve.

Sleeves sinking are also due to poor sleeve design.

[Neanderthal Racing]

Originally Posted by Darton Sleeves

Depending on the manufacturers sleeve design they may have to rely on cement or epoxy which will cause issues. Temperature issues will depend on the type of cement or epoxy used. The main problem with using cement or epoxy is that they are too hard or if there is any movement with the sleeve it will turn to dust. If there is any movement due to expansion the cement or epoxy will crack.

that is pretty much what i understood has been happening in some cases. thanks for the confirmation.

Originally Posted by Darton Sleeves

We supply and use 518 Loctite with all of our MID and Seal Tight sleeves we supply. The 518 is good up to 300 degrees and remains flexible. We also use o-rings to seal the sleeves so sealer in not necessary on the bottom of the sleeve.

Sleeves sinking are also due to poor sleeve design.

is there a correlation between egt's and the temperature at the cylinder sleeve where it is likely to affect adhesives?

[Flycaster]

One more question for the pot, if I might: Can't you use stepped sleeves, and if so, won't this eliminate the possibility of sleeve "drop" altogether?

[srt42sti]

Originally Posted by Neanderthal Racing

sounds like there's a story there.

not me thank god.

[Jeremy@Cobb]

The sleeves that Darton offers for the EJ25 are T-sleeves, this upper flange rests on the factory aluminum which used to surround the factory Sleeve.
These Darton sleeves bottom out on this upper flanger allowing the new sleeve to sit true, and not allow the sleeve to sink.
Out of all the sleeved blocks I have sold "." , I have not had one issue, which means absolutely no sunken sleeves (most of these are driven on the street).
Like Darton said above, 99% of failure is due to poor machining and/or installation.

[Flycaster]

That's what I remember seeing from Mick's posts on NASIOC. How could that sleeve possibly drop if the cylinder is properly machined to fit those 3 steps?

[gohrsepwr]

so how does cosworth sleelve thier blocks?

[parkergc8]

They would be the best people to ask.