Red Line

Still being pretty new to the world of Porsche. I had the #4 cylinder crack. So it looks like a top end re-built is in my near future.

* Is there any-thing I should have the mechanic look @ while the motor is open?

* Also about how much am I looking to shell out for a top end re-build?


Many Thank

Regards,
Eric

Geoffrey

The top end rebuild typically means that everything from the heads and above are removed, inspected, and rebuilt as required. eg heads resurfaced, valve guides replaced, valve job completed, possibly springs and retainers. Camshafts and cam towers inspected, rocker arms evaluated and replaced or rebuilt as required.

When you say you have a crack in the cylinder, that is more the bottom end of the engine. What cracked? and How many miles? You might be better off replacing the pistons and cylinders as a set so they have the same weight and height groups. You'd probably want to replace the rod bearings if you have some miles on the engine..

Boeing 717

Do they have to remove the engine to do a top end overhaul??? A porsche mechanic once told me about 6000 dollars to do this does that sound about right???

JERRY

Indycam

Whats the leak down numbers for the other cylinders ?

Red Line

I'll check on the leak down #

I give you guys the short version of what happened. I bought my dream car from my dad. He let the car sit for almost 2 years. It is a very fast 528 HP and 539 TQ 964 C4 built by Turbo performance center in Maryland. I took the car home of Monday night. Tuesday when I got home from work I took her out for a spin. Well I thought my dad drained the fuel out of her but he did not. The mechanic said it looks like the old fuel detinated in cylinder 4 and cracked. He said this was from running old gas. The motor has ARP Bolts, TBC molley coated pistons.

Also can some one tell me what a reman split case and a knife edge mains (flow case) is . I'm just looking @ some of the receipts from TPC.


Thanks,
Eric

Red Line

Hello the motor has only 55,000 on a 1992. And it looks like the motor was built up in 1998 with 33,000 @ Turbo Performance center.........

Indycam

"reman split case"
They split the case apart and redid the thing ,

"knife edge mains (flow case) "
Custom grind the main throws and the case .

Indycam

"I'll check on the leak down #"
If the leak down numbers on the other cylinders are ok and an oil test tells of no damage , I'd just fix whats broke .

Red Line

I know when I was standing in the garage. They put the motor to top dead center and messed with the leak gauge. the sound of the air leaking out was coming from behind the cooling fan. This is when he said it might be a cracked cylinder. Hey then said he would start tomorrow by taking the valve cover off and that will tell him a little more whats going on.


Thanks guys for your info............

darth

what happened when you took it out for a spin Tuesday after work?

stevepaa

Old fuel detonating? Does anyone know any history of this?

Be ready for $15k if the mechanic has to do this top end for you.

If you have the inclination and patience , do it your self.

Geoffrey

It sounds more like the cylinder to head mating surface has burned through, usually from running lean rather than detonation. Old fuel and turbos on boost is never a good combination.

stevepaa

How does old fuel degrade? Loss of volatiles?

Seight

Wow! The thing that stands out on this thread for me is that there was a 500hp+ 964 standing around for two years with no one driving it! Crazy.

Cheers
Alex

Red Line

I took her out after I got home from work got on the boost about 10 times. Brought her back home for a bath and tire shine. After that I went out again. I left the drive way and got on the main street and got on her when I saw a Yamaha R1 racing down the street. I pulled up to the light and some smoke came in through my window. I pulled her over and there was some oil hitting the muffler from was coming from the block. No smoke coming out of the exaust tip just burning off the muffler. The tone of the motor went from a Porsche sound to a VW bug sound. The oil pressure was @ 5 bars for the short ride home.