Hello all, a few questions from first time SC owner

Strictly · Dec 30, 2007

Hello All [

]

After much hardwork and a big promise to myself I have finally achived a Porsche 911. Its a 1979 3.0 SC, am very happy with it, it needs a bit of work, but working on cars is what i love, so look forward to it.

I have a few questions, I would be very gratefull if someone could answer. I'm a time seasoned VW mechanic (air and water cooled) but Porsche 911 is a new one for me. The car has 58,000 miles (belived original, and I am in the south west of england).

Oil Questions

A) The guage next to the fuel gauge? Is that Oil Level? Is it normal for it to start in the red with the engine idling from cold, and then stabilize. Where is the best place for it? It seems to start in the red and settle near the top when idling on a level surface with the engine warm. I checked the engine oil at the time, but it seems to be quite a bit over the maxiumum, with LOADS of little tiny bubbles in it (normally thats a head gasket indicator on water cooled engine)

Oil pressure, seems to be a piddly 1 bar at Idle when warm, and about 3 bar max, when at speed (engine warm). Is this good, medium or bad?

I think Ive heard a little puff of white smoke is perfectly acceptable on a 911 at start up - any comments?

Which Oil should I use for an Oil Change 15/40 Semi, or a straight weight oil like SAE 30? Should I use Two cans of engine flush, because of the amount of oil in the system (no oil cooler in front wheel well on mine)?

Engine Tuning.

Ive found the idle speed adjustment, where is the CO adjustment? I have access to a CO machine and all the right tools plus know how. Should I am for a CO of say 2.5% at idle, once I have set/checked the ignition timing

I have a few other questions, like do you remove the engine and gearbox to change the clutch, but I will ask those at a later date.

OWNERS MANUAL

Anyone know of a owners manual in .PDF format? If not I'll keep a good look on ebay for one. Anyone reccomend any particular books for the SC?. I allready have a haynes manual and a few Porsche 911 buyers guides, red book, etc

MANY THANKS for taking the time to read this, and would very much appreciate any usefull comments

Luke

nick3814 · Dec 30, 2007

Hi Luke, well done in owning a 911sc, I hope you find as much joy in ownership as I do with mine, its a few years younger than yours but basically they are the same.

The oil level gauge!!! Generally you find they have a mind of their own! How you describe yours working is the same as mine, once its warm it reads around the top of the gauge when stationary and on level ground. Its important only to use it as a guide the best check is with the dip stick, I've known mine have a few bubbles in it before but once its been on a good run they disappear and I've had no problems with mine in the past two years.

The puff of white smoke on start up is perfectly normal, there is that much heat in the exhaust I believe it generates some moisture in the system once it cools down and when started again comes out as white smoke (thats how it was described to me when I first started!!) if that makes sense?

Oil mmmmmmm!!! I've used Castrol Magnatex for a while and then tried a fully synthetic 0W/40 which just seemed to identify leaks as it was as thin as water and it used a litre or so over 12 months as well so I prefer the semi like Magnatex and will be going back to a similar oil this spring but you will find vast opinions on this where ever you look.

Co adjustment, its hard to describe but here we go, I believe yours will be the same as mine. As you look at the engine the throttle housing on the top of the engine has a large rubber dome to the left and the metal fuel distributor with the fuel lines coming out of it to the right. In between is a small hole with an adusting screw in it, you can't see it but use a 3mm allen key (long one) eventually it will find its way through the hole and into the screw. Clockwise is rich, CCW is lean.

Here are a couple of sites to help you, there are some excellent forums out there as well as this one.

http://www.pelicanparts.com/index.htm

http://www.impactbumpers.com/index.html

This is a good one to help with the CO settings etc

http://members.rennlist.com/jimwms/CIS/CIShome.html

A couple of good books out there are the 911sc Bently manual which I've still not got round to getting (its a bit pricey) and Wayne dempseys 101 projects for the 911 (hes the guy who runs pelican parts, very good).

Hope this all helps mate, any more questions don't hesitate to ask [

]

Cheers

Nick

GeoffB · Dec 30, 2007

A good site to visit is www.cannell.co.uk not only does it contain superb event photos i believe Rick has now added workshop manuals you can download
Good luck with the car i had an SC for over 9 years and loved it!

steeley · Dec 30, 2007

My 3 fav. Porsche books for the budding mechanic:

Porsche 911SC: The Essential Companion
by Adrian Streather

Porsche 911 SC Service Manual 1978-1983 (Bentley)

101 Projects for Your Porsche 911 1964-1989
by Wayne Dempsey

I've been using 10w40 semi oil in my 82 SC. Have fun tinkering!

cheers,
Ian

Strictly · Dec 31, 2007

Wow thank you for the quick replies!

Ok that has relaxed me on the oil level, as it seems to be normal! Thats a good tip about keeping it 3/4 full so it dosent overflow on a hot summers day, also if its anything like the air cooled beetle engine (better engineered of course) then you run these about the same, as otherwise they blow the crankshaft/flywheel oil seal regularly.

The oil pressure, seems to give me at best 3 bar, but I am going to give it a flush and oil change and go from there. Is it worth installing the Oil Cooler as on the later models?

Is that temperature guage the Oil Temperature or Cylinder Head Temperature?

A few more questions if I may?

I was reading that you shouldn't use the accelerator to start the engine as it can blow up the air box. Earlier Models (?) Had a hand throttle level by the hand brake that you would use instead. Mine only has the heating one, so what is best way to start? (Actually it starts very well without touching the accelerator, i just dont want to blow up the air box).

I can hear a knocking from both passenger front and rear suspensions (and a rear wheel bearing, and both heat exchangers are rotten, and the clutch needs....theres a bit of a list, ive got a my work cut out for me, but what else are you supposed to so with your life (dont answer that!) [

])

Ok, as i was saying ive got a knocking on the front, it sounds like the strut top mount, the suspension feels a bit tired, go going to change the shock absorber. What make (Blisten, Koni, Etc) would you recommend? Oil or Gas Shocks? Do I buy the strut as one with the spring, or change the shock absorber and spring as in typical macphearson strut assembly?

The rear knocking i'm presuming if a tired shock absorber not doing its job, and allowing the car to hit the bump stops, i'm going to have a proper look, but does that sound about right as a starting point?

Thanks for your help, I'm going to join the club, and you will see me often on this forum, as mechanics are in my blood so like to help others and be helped.

Also thanks for the info on the books, I have orderd the 101 projects and SC companion to start, and the bentley manual in time...

Luke

steeley · Dec 31, 2007

I never touch the accel. when starting my SC. Always starts easily even if it has been sitting for a week in a cold garage.

Rusty heat exchangers can be quite difficult to remove - luckily for me one of the PO (previous owners) had put
stainless steel ones on. SSIs are supposed to be good heat exchangers, and give a bit more power.

cheers,
Ian.

bones · Dec 31, 2007

Hi welcome to SC ownership, probably the best 911 ever! [

] CO for your '79 SC IS 2.0-4.0, personally I think they run better a little rich and with a slightly higher tick over speed although you will find out that idling speed varies according to engine temp and ambient condition, recommended idle speed is 900 +-50rpm. Oil pressure should read 5 bar - max - when accelerating and up to 1bar when idling. If you are not gettting full pressure suspect the sender, a connection or the clock before you decide the pressure is low. Try checking and then cleaning the contacts on the sender first. Forget fitting an extra oil cooler unless you do loads of track work. You read correct info on starting the car, don't use the accelerator and fit a 'pop-off valve' to prevent blowing up the airbox, (it does happen particularly the early SC models like yours). Knocking from the reAr could be a drive shaft , if you want to replace the shocks check what type you have by looking at the colour, 'sport model' cars have green Bilstein as standard.

Strictly · Dec 31, 2007

Great advice - ill fit a pop off valve and check the oil pressure sender first then go from there. A Happy new year to you all, Im away for a few days, but will check back on the 2nd, please feel free to keep making any comments you think I will find usefull. Loving the porsche! I promised myself one for xmas, and worked very hard to get it (i dont earn alot, but thats cornwall!). Very happy, and even happier to know that there is such good advice at hand

[

] [

]. Luke

nathan 1981 930 G50 · Dec 31, 2007

Bilstein are the best shocks/struts. You can buy just the inserts for the front.

The temp gauge is indeed for oil temps.

desilva · Jan 3, 2008

Luke

I have a 79 SC, it came filled with Mobil One fully synthetic oil. The engine leaked a bit and used a lot of oil. I have now swapped to Millers classic mineral 20/50. What an improvement ! normal oil consumption, quieter engine and better oil pressure (about 1.5 bar idle 4.5bar at about 5000 rpm).

I would recommend a standard 20/50 oil like Millers or Duckhams next time you change your oil.

By the way mine puffs a little bit of smoke on start up but soon disappears.

Good luck

Phil