Engine rebuild - Project too far?

[Elliot]

I have a 162K totally original 911204 BHP SC and i feel she deserves a rebuild.

She has a small leak from the main bearing seal, the heat exchangers are shot and there is a leak near the oil tank.

Contemplating spending circa 5.5K on a rebuild i then stumbled on a former ferrari and porsche 356 mechanic down the end of my road. We got talking and he agreed that if i help him put some florring in a workshop he will teach me how to stripand rebuild my girl.

He did say i wont do it if you dont want it done properly - which i found reassuring as this is what i wanted.

Anyway, i will be posting progress pics and postinga n article in the Porsche Post no doubt but before i do i need the following advice.

Where should i source all paarts i need:
has anybody any experience of the pitfalls
Does anybody have the proper tools to save us making them (will hire them if poss.)
I need all measurements and tolerances-where are these published
Is there a good book/s on rebuilding an SC
Any good methods for cleaning and laquering parts
Anybody got some ss heat exchangers for sale?
Any other bits i should look at while i have the engine out.

That should do for now.

Thank you in advance for any advice / links

Cheers

Elliot
R4 Regional Organisor

 

[bones]

Hi Elliot,
Nice project I'll venture there myself one day and you are lucky to find an experienced mechanic to help for free nearby. BUT - why are you rebuilding? If it is for the reasons you gave then forget it at that mileage and a well looked after SC should still be running well, was it smoking on gear changes? Did you have low oil pressure? Or do you just fancy blowing 5k on your hobby? [] You may find once you start rebuilding one of these engines 5.5k dissapears rapidly once you get into adding on SSI HEs and other ancillaries and you'd want it to look good too, wouldn't you? So engine detailing comes into the equation, that involves bead blasting casings, headers etc, it all adds up to big bucks, do loads of research first but only do it if you have a contingency budget and the engine needs it. The main bearing leak is probably liveable with, the other things are easily fixed.

 

[Laurence Gibbs]

To answer some of your questions. For parts any reputable Porsche parts supplier and always go for a good quality gasket set. skimping is a false economy. I would recommend the Porsche tech spec book for all engine specs and tolarences these are or were still available from places like Type 911 etc as is the factory manual set on fische, though you can probably get it on cd by now. Both books are a minimum for an engine rebuild in my opinion. The Bentley SC book is also worth while. Tools ....many of these can be made if you have the inclination or purchased via companies like pelican parts in the states. You would prbably need as a minimum the camshaft nut tool, valve clearance tool and the go/no go valve guide gauge along with a good quality engine stand and yoke(i've probably missed a few must haves here due to brain fade). I would guess your engine builder friend would have mic's etc? access to a press is useful for pressing in the guides. other machining work is best farmed out. I recommend using the correct loctite for the cam cases and you might also like to get hold of the little seals that fit onto the rocker shafts as extra insurance against leaks. If your SC does not have them , update to hydraulic chain tensioners too. Heat exchangers are a matter for personal pref and your wallet, when deciding on ssi or steel. At 162k it would be prudent to strip the bottom end as well as doing the top . Worth checking the condition of the crank and oil pump and intermediate shaft for wear. Hope this helps.

 

[Elliot]

Thank you for replies

i understand why you are saying why bother but the oil takes a long time to heat up, the car does not idle properly - despite changing idle valve. I feel that a rebuild would help to solve these problems and give me an unpaid course on the inner workings of a 911 engine and how to build one.

If anybody out there thinks that they can solve the issues i have without a rebuild and is willing to have a look at her for me i will have a drive out and meet up.

Cheer

Elliot

 

[bones]

Blimey Elliot , they are definitely not reasons to rebuild one of these engines, oil taking a long while to heat up isn't a problem, you're probably not driving it fast enough! In your region you should be able to find a specialist to look at your niggling problems and hopefully it won't brake the bank, these cars have to be set up with diagnostic equipment. Idle isues can be caused by a faulty WUR, fuel pressure problems and general faults with any of the CIS system, then there could be faults with plugs, plug leads, rotor, sticking/faulty advance, dirty/worn injectors, minor electrical niggles, a long list which a specialist would go through to find the problem. A car of this age should have a recent OEM plug lead set, new injectors, new battery and when you've got to the bottom of your problem a full service including setting the valves. Ask around for who take an SC too before you spend any money.