New Piston & Cylinder - Damaged! What now?

Navaros911 · 07-22-2013, 12:31 PM

So after establishing I need new cylinders and pistons, I found a great deal on a new set... bought them, they arrived last week... and one is chipped.

Not sure if that is the reason it was a great deal or if it happened in transport, but I didn't find anything in the box. It was an open box item, reported to be in perfect condition.

So... what now?

The pictures are below and the damage is small. So I wonder what the effect would be if it would end up being used anyway.
I'm also thinking of buying a single piston cylinder that matches worst case scenario.

Fortunately I got the set at a very good rate.... but it's kinda useless if I'm short one cylinder.

What do the experts think?

john walker's workshop · 07-22-2013, 02:38 PM

it actually seals on the inner ring, FWIW.

EBS racing may have a single cylinder.

Navaros911 · 07-22-2013, 03:52 PM

So it should seal fine and the outer lip is only to hold the seal in place. With a little piece like that missing all it would do is expose the seal a little.

Worst case I guess a small oil leak would develop a bit earlier... not something I'm concerned with... as long as the compression is fine.

Thanks for the tip on EBS.

304065 · 07-22-2013, 05:52 PM

send to ollies. not worth taking a chance once it is together.

Navaros911 · 07-22-2013, 07:13 PM

304065: Who is ollies?

Jack Stands · Jack Stands's Garage

Ollie's Machine Shop located in Lake Havasu City, Arizona. Their phone number is 928-855-6101 and email is ollies911machine@yahoo.com. They could probably give you good advice, though I see you do have a bit of a distance to ship this to them.

AlfonsoR · 07-23-2013, 10:16 PM

I guess Ollies would weld it? I would be concerned with welding. If it must be right, i would rather try to find a used one. Otherwise, use it as is.

earossi · 07-24-2013, 06:15 PM

I would be concerned about attempting to repair the cylinder. Better to take a used cylinder and send it off to have the cylinder refurbished. The cost will be about $200 and should provide a cylinder that is as good as new. There are several US companies that perform that type of work. I suspect that you can find a similar service in your part of the world.

safe · safe's Garage

Quote:

Originally Posted by john walker's workshop

it actually seals on the inner ring, FWIW.

EBS racing may have a single cylinder.

Will the seal/ring fail in the long run when it lacks the support?

earossi · 07-25-2013, 07:56 AM

Quote:

Originally Posted by safe

Will the seal/ring fail in the long run when it lacks the support?

That is difficult to answer. Any break such as occurred here, at the very least sets up a stress riser that could serve as the origin for cracking. Since these cylinders grow and contract as they heat and cool, any stress riser could become the origin for another crack.

If the OP wanted to gamble and re-use this cylinder, it would be best if he files/grinds out the break crater to remove any sharp edges and to blend out the edges. That will go a long way towards removing or minimizing the stress risers I mentioned above. This comes from my background as a structural engineer.

Neilk · 08-03-2013, 08:27 AM

Can you find the part that chipped off in your box? If not, that may be the reason for the good deal.

Good luck.

Navaros911 · 08-09-2013, 01:54 AM

Neil,

No I didn't find the chipped off part in the box... but I wasn't the first on the scene.

My wife flew out to my mother-in-law in NY... she unwrapped at least one (as they wrapped in a plastic bag). So it could have fallen out then.

In any case there is no way to be sure, but I do find it suspect.

Ordered me a single P&C as replacement. So I should be good, but haven't seen it yet. Will see next week when I get back to NY.

afterburn 549 · 08-09-2013, 03:57 AM

Follow Jn Walker
Stop the non sense.
It is NOT part of the sealing surface.......stop telling people its chipped, No one will ever know ..
and - you will for get after a short while
You weld that little piece of crap on you might just not have a round cylinder anymore

Navaros911 · 08-09-2013, 05:03 AM

Afterburn,

While I believe the car will run with this piece chipped off, the cost for rectifying this to me is just over $300... so I figured I'd spend the little extra cash to have a perfect set.

If it wasn't my daily driver and I was doing the work myself (no space yet and definitely no time) I'd use it as is... combine that with international shipping if I need anything where I live and that money will just evaporate if anything doesn't quite work out.

So I took the certain for the uncertain... and this will remain one of those "we will never know from experience what the effect on the car would've been".

The little piece is missing anyway... so I wouldn't be able to weld anything on anyway.

Henry Schmidt · Henry Schmidt's Garage

Quote:

Originally Posted by john walker's workshop

it actually seals on the inner ring, FWIW.

EBS racing may have a single cylinder.

I agree with john in that the compression is sealed by the inner surface of the cylider.
The gasket is designed to prevent weeping on cool down so any damage to the support of the gasket can bring into question the integrity of the seal.

If possible, I would replace the cylinder.

That said: Since the gasket is there to prevent weeping and the lips in under very little stress, perhaps the lip of the cylinder can be repaired with a high strength, machinable epoxy. Many of the new heat cured epoxies resist the temperatures in excess of 600 degrees.