75 911S purchase

[millwall]

Decisions Decisions!!

Have chance to buy 75 911S 2.7 with 59,000 miles.

The local Porsche Mechanic who inspected it says its a tidy car with no rust but the engine has pretty much reached the end of its life and wants to quote me on a rebuild or replacement ($$$). I understand those middle years had very short engine life spans.

The porsche dealer who is selling it says the problems the engine has can be fixed without having to rebuild or replace (for example, putting an additive in the oil to thicken it?). I'd appreciate some feedback on who is right and what options there are....someone may have experienced the issues below before...cheers guys

Engine compression even 115/120 FT/LB (recommended 150)
Engine oil pressure low (but seems to be ok once warm and running)
Timing Chain Rattle
Engine running rich
Ring gear worn
Timing chain worn

Mike C (down under)
75 911s (under review)
85 BMW 318i
95 Audi 80 v6
2005 997 (just to keep the pattern going of course)

[jluetjen]

IMO, Using addititive and such is just a short term crutch. How long has the car been sitting? After some use the compression may tighten up some.

I'd negotiate the seller down and figure that you'll need to purchase Wayne's book and do a rebuild in the short to medium term. Check the compression again after a couple of weeks of use. If you are going to track the car, it will definitely need a rebuild sooner.

[k9handler]

what updates have been done to the motor (chain tensioners, etc.)? Also has the trombone cooler been replaced with a Carrera type? I ask these questions because if the engine was maintained and with these mods the cooler running temps it's a known fact the life of the engine would be greatly increased. If it's due for a rebuild, get the seller to go down on the price to assist with it.

[Silveresrty911S]

Mike,

I picked up my '77 with a 3.2 that had been done about 2 years before I bought it. The car has no rust and needed a paint job, windshield and a bunch of misc items to bring her back to a very nice (not concourse) targa.
I paid 10,000 US over a year ago and did alot of the work myself, depending on the asking price you could do a 3.0 or 3.2 swap for about 4,000 - 6,000 if you do most the work your self. I think even a top end rebuild for those are around $4,000 depending on shape.
If it's a clean car that doesn't need much other than engine work and you can get it cheap enough Go for it, they're alot of fun to work on as long as you don't go overboard

Rick

[Rouxzy]

Like K9 says, it depends on updates that have been done to the engine. Mine has over 140k miles and still has not seen any engine work, but my engine has received all updates. Don't use oil additives in these engines, it'll end up doing more harm than good. Chain rattle could be worn ramps, does the engine have the updated tensioners? Check to see if it has the updates and get back to us.
Tom

[Loual]

If the car needs nothing but an engine rebuild, it may be a good deal at the right price, but the right price should be a lot less than you'd pay if the engine was in the same shape as the rest of the car. For your money, the best value is to fnd a car where someone else has done all the work including rebuilding since, unless you do your own wrenching, a complete rebuild of a 2.7 can cost half to two-thirds of the value of the car.
Good luck! These are fun cars.

[azasadny]

Mike,

Lots of good advice here. My '74 has an engine that could stand rebuilding, but has the Carrera-style front-mounted oil cooler and the engine runs cooler with it. I change the oil frequently (Castrol 20w50) and Swepco 201 in the gearbox. Buy the car and enjoy it, but don't go crazy or you'll just be spending alot of $... Enjoy the car and post pics when you get it!

[vash]

i have a 75 with 49k miles on it. i have blasted through roughly 2k worth of repairs. some to prevent damage, some to fix it. i think everyone above covered the issues. remember, you will need to get a 11 blade fan, cooler, rid of the reactors. etc. still alot of fun. if the dealer know an engine rebuild is looming in the near future, work that into the final price. i love my 75. it is like a rubic's 911, a puzzle. but i am getting it. i am getting a external cooler system tomorrow and chain tensioner soon afterwards.

[yelcab1]

So, if a clean 75 911S goes for $10K in the US, I personally would not pay anymore than $5K for this car in this described condition. Oil additive is a joke of a recommendation. You are buying a shell at this stage and you still have to remove the engine to get to a shell.

A full rebuild in the US is $8,000-$10,000 if someone does it for you.

[anh911]

It's a good question if you have to farm out the engine rebuild later on. If you can do it yourself then go for it. I would check into the oil pressure issue first and the timing chain. Sounds like it doesn't have the tensioner update. Also, the middle year cars have a bad rap primarily cuz the US cars had reactors, insufficient oil cooling and operate in much higher ambient temps than the euro cars. If this is a NZ car from day one it might have suffered less from the heat.

Finally, I wonder about the rich running? A Porsche dealer selling this car would (should) at least do a basic tune and adjust... What do they say is wrong with the car?

[Zeke]

Originally posted by millwall
Decisions Decisions!!

Have chance to buy 75 911S 2.7 with 59,000 miles.

The local Porsche Mechanic who inspected it says its a tidy car with no rust but the engine has pretty much reached the end of its life and wants to quote me on a rebuild or replacement ($$$). I understand those middle years had very short engine life spans.

The top end needs attention at 60,000 according to Andial. And the chain tensioner upgrade should be done. (I should talk, I have yet to do that) Total rebuild should be unnecessary except many say if you've gotten that far, why not go all the way. I tend to take that with a grain of salt.

The porsche dealer who is selling it says the problems the engine has can be fixed without having to rebuild or replace (for example, putting an additive in the oil to thicken it?).

That scares the hell out of me.

[dmac]

The dealer wants to sell the car, and the mechanic wants to get a rebuild project - you cannot trust either. If the car has not been driven much lately the compression may come back in a few thousand miles. Noise in the valve train is normal - but you may need valve adjustment, or perhaps a new tensioner - neither are huge projects. Don't put additives into the engine. I say get another opinion - someone knowledgable about 911's but who has no vested interest in your transaction.

[catuck]

If you can get the car for 7k or less, it could be a great deal as long as the only problem is the engine. If you do decide to buy, cut your losses now and don't invest too much money into the engine. If you can get it running with a few hundred bucks, go for it. but 2.7s usually leak oil and are nearly impossible to seal and only have about 165 hp. For 5k you can drop in a 3.2 with over 200 hp. The nice thing about the '75 is it's light and with a bigger engine, a ton of fun.

[Randy Webb]

The things above are nice but not nearly as critical as the internal strengthening of the case, etc. You need to read the engine chapter in Bruce Anderson's book before buying this car.

Also, is it a Calif. model? That's bad. The 'good' 75's are the ones in the PNW or maybe Minn. where it stays cold.

I have a great 1975 S -- but the PO put $50k into it -- no lie.

[jase007]

Mike C:

I agree with what has been said and would also add not to be scared of the middle year cars. I have a '76 targa with 164,xxx miles on it and it still runs well enough to track every once in a blue moon. (no thernal reactors) PO cracked the case but not sure what was done. I have NOT installed pressure fed tensioners or carrera cooler. Car normally runs 190 - 215F here in Northern Virginia summers. (have 11 blade fan and no air conditioning) The car can't really take track running b/c oil temp shoots right up to 230F after three laps.

I would NOT use oil additives and I would check on the valve adjust. There is an low oil pressure fix using (964?) pieces to increase pressure, especially at idle. If you could get it for under $7K US then you'd be sitting pretty for when that 3.2 deal comes along.

Jason

[Aussie]

Why not take the car to an independent body shop, to make sure the body is in as good a nick as they say.

Major body work is lots more expensive to fix than major mechanical problems.

If the body is in really good nick and you can afford a engine rebuild on top, and you like the car then buy it.

But factor in an engine rebuild on top of what you are paying for the car and then also decide if you could get something better for the same money.

[millwall]

Thanks for all the advice guys...have talked to third party porsche mech who has rebuilt over 200 911 engines and he use to service this exact car before the past owner traded it in to the place that is selling it now. He has quoted me NZ$2000 (approx US$1300) to fix the problems if the engine oil pressure isn't an issue. It hasn't had the Chain tensioner update and I have subsequently discovered it was a california car from 75 until 85 when imported to New Zealand. I'm pretty confident of my offering price now, anything more and I'm walking away. Just that this era 911s are hard to come by down here...cheers again guys...will keep you up to date on what happens

Mike C

[vash]

you better keep us posted. i love this stuff!

[nostatic]

well, the head studs need to be replaced with timeserts put in the case. Then the tensioners, and top end if everything else is OK. $1300 won't do all that. This sounds like a very tired 2.7 that needs to be rebuilt right. It won't be cheap, but if the rest of the car is solid you'll have a pretty bomproof ride afterwards.

[aigel]

The engine is the most expensive part to fix, period. There is no telling what you get yourself into. I would not buy this. Rather save some more and buy something that doesn't have any current issues. Buy a car that runs, makes no noises and has compression you feel better about!

Dnyamic compression numbers have to be close to each other, within 10%, the absolute number is completely meaningless. It depends on things like barometric pressure, temperature, the cranking power of you starter and maybe even the phase of the moon!

As nostatic points out, the problem with the 2.7, besides the valveguides is the fact that the magnesium case isn't very strong. As Bruce Anderson once put it: "Magnesium is no real metal, it wants to go back, being beach". Unless you have the case fixed with inserts for the head studs, it will not be the question IF the studs pull, just when they will pull!

And it was a california car for 10 years. GREAT! That will be good in the rust department, but it will have had the thermal reactors that really helped kill the engine quicker than anything else.

If anyone recommends additives to fix a mechanical problem, they are full of menure. I'd refuse doing business with them. Who knows what other 'fixes' they already applied to sell the car.

Cheers, George (who is usually an optimist!)