911 SC Issues-need advice

[lyonsfin]

I purchased aN 83 SC in November w/127K miles that had been gone through. It had an oil leak that was to be fixed. I moved the car (BY TRAILER) 1000 miles for the winter. The leak persissted and I took it to a local porsche expert. He called this morning and said the oil leak and cold start issues were minor (temp sensor & oil switch). He checked the car out and found that the transmission case had been sealed w/silcon (red) and not leaking. Some noise that sounds like 5th gear synchros. Also, there are 3 heat shields missing on one head. He thought that the engine should come out, transmission sorted w/ new gasket set, full valve job and new heat shields w/new head studs and fix oil leaks. I was planning on a few hundred dollars and it turns out to be $4500. Engine runs well, a little white smoke on startup (& sometimes a backfire). No blue smoke. Mediocre gas mileage. Temp gauge in city driving is at about 7-8 O'Clock. How important are the heat shields (he seems to think it would be bad to drive it too much) and can they be replace w/out taking the head off?
Thanks

Josh

[TechnoViking]

Hi Josh,

I don't know if the heat shields can be properly installed without an engine drop..but I'd guess they can be with the proper motivation (like not wanting to spend $4500).

Sounds like your car is running hot. Have you checked to make sure the oil thermostat is working? Is that what your mechanic means by "oil switch"?

Make sure the thermostat is working by getting the car warm and felling the oil lines forward of the thermostat (in the right rear fender). If it is working, you may want to consider an upgrade to the "carerra cooler" which is a much better oil cooler (in the right front fender) than the trombone style that comes in the SC.

I'd do those things to get your temp down, and then postpone the engine drop and tranny work until something needs to be fixed. Just my $0.02.

[lyonsfin]

Thanks Martin. I didn't think it was running hot as the needle is just above the second bar and definately below the 9 o'clock position. It seems steady there. I am not sur the car really needs a valve job, but if the engine comes out, I guess it makes sense. Thanks for your input. I'm tempted to have the oil leak fixed and then decide what to do.

[Peter Zimmermann]

If the leaking "oil switch" is the one on top of the front of the engine, that will require a partial engine drop (at the least) and be sure that the thermostat o-ring is done at the same time. Also, check/replace the crank breather hoses if necessary, as well as the the throttle lever bushings.

The heat shields are another matter. Someone probably was in the engine for valve-related problems (failed chain tensioner/guides?) on that side, maybe a broken head stud, and they didn't get put back. To install replacements you will have to remove the heat exchanger and oil return tubes on that side, and remove the alternator and its housing from the top of the engine.

I've never been faced with a "follow-up-the-dummy" repair such as this, but I "think" that you can do the heat shields as above. They MUST BE there! Regarding your oil temp, if the gauge needle stays below 9:00 you are good.

[Peter Zimmermann]

Originally Posted by lyonsfin

He checked the car out and found that the transmission case had been sealed w/silcon (red) and not leaking. Some noise that sounds like 5th gear synchros.
Josh

Please try to expand on this noise issue. Synchros don't make noise, and I'm curious to learn what you're hearing - especially if the same guy had your trans apart that forgot to install your heat shields (red silicone sealant is a tip-off that it was)!

[lyonsfin]

I'm sorry, it is the gear shims. It is a not very loud and sounds like a clicking or ding, ding noise. Only audible from below the car.
Someone had mentioned to me that there are expandable heat shiels that can be put in. Anyone know anything about them?

[Vincent Hill]

My Question is, Are you Mechanically Inclined yourself?

If you are not, then think at least think about at least Doing a "Compression" Test yourself! This will tell you If you need a valve job. You can get a good enough compression tester at Harbor Freight tools for less than $25 or so. Pull ALL of the Spark Plugs After you heat the engine up. Then one at a time do each side of the engine and have a squirt can with Motor Oil in it. After doing 1 cylinder Squirt a shot (no more than 2 Squirts) of oil in the same cylinder and recheck the compression. It should go up. If it does not go up and the pressure reading is below 100, You will need a valve Job.

BUT, If you check all of the cylinders and they all read between 120 and 150 PSI with the Oil Squirt, Do not get the valve job and save that until later.

Also ask the dealer "How much" for the same work "Without" the Valve job! It should be at least $2,000 or MORE less! They usually charge about $1,000 to drop and raise the engineI figure another $500 to remove and replace the Exhaust / Heat Exchangers and replace the Heat Shield / Heat Deflectors. and maybe $200 labor for the temp Switch and Oil thermostat.

All less than $2,000 5th gear will always make some noise because it is an Overdrive gear and they get a lot of wear. Put in Mobil 1 full Synthetic Gear oil or some of the other Highly reccommeneded Oil and enjoy you car.

If you are Mechanically Inclined, then get a Bentley Service Manual and drop the engine down in Back and take your time to remove the Fan cover and replace the Shield yourself!

Think of your Porsche as a 4 wheeled Motorcycle and not a lot harder to work on!

[Superman]

It's probably possible to install air deflectors without removing the heads, but the result will be some pretty mangled deflectors. Even with the exhaust removed. When I rebuilt my engine, I had the heads on by the time I noticed I had neglected the air deflectors. Nothing else, just heads. After studying the problem for a time, I elected to buy new gaskets and head/cylinder aluminum seal thingies (not cheap) and remove the heads in order to install the deflectors. As I say, it is probably possible without removing the heads, but the deflectors will be fairly mangled.

[Vincent Hill]

Originally Posted by Superman

It's probably possible to install air deflectors without removing the heads, but the result will be some pretty mangled deflectors. Even with the exhaust removed. When I rebuilt my engine, I had the heads on by the time I noticed I had neglected the air deflectors. Nothing else, just heads. After studying the problem for a time, I elected to buy new gaskets and head/cylinder aluminum seal thingies (not cheap) and remove the heads in order to install the deflectors. As I say, it is probably possible without removing the heads, but the deflectors will be fairly mangled.

You might be right, It has been so long when I had my 1976 apart, I do not remember! I do know that they have abar that holds them down that runs across the cylinders and U Shaped on top to stay between the Cylinders. I do not remember how they fit at the head!

[mholbrook38]

Regarding the oil in the Transmission. Do not use Mobile 1. Use Swepco. It is widely recognized as the best lube for the SC cars with 915 trans. I might add that it will take a while to really do its thing. I changed mine and now at about 3000 miles later, she is smooth as butter.

Part of that smooth as butter however may well be that I am now more in "tune" with the car.

[80-911SC]

ditto on the swepco gear oil , NO MOBIL 1 in the 915 tranny .......

[Peter Zimmermann]

NEVER use synthetic oil in a 915! With regard to Swepco, it is NOT the "only" fluid out there that does the job in 915s, as a matter of fact it might not even be the best. Kendall Three Star 80w/90 Dino oil is a superior product, somewhat hard to find, but in every respect is a perfect lubricant for your transmission.

[lyonsfin]

I spoke w/the shop where I purchased the car and they insist that they did have the head off, replced the head studs, checked the valves, etc and they were fine, and replced with new head gasket. So, I will find out if the heat delectors can be installed without taking the head apart, and, at least, it won't need the studs replaced and a valve job.

[80-911SC]

re read your last line "you talked to the shop that ..... they had it out and replaced ... they were fine "

they would also be the dorks that left the cooling tins off wouldn't they?

How much would you trust them , they already lost my confindence .........

[boyt911sc]

Originally Posted by lyonsfin

I purchased aN 83 SC in November w/127K miles that had been gone through. It had an oil leak that was to be fixed. I moved the car (BY TRAILER) 1000 miles for the winter. The leak persissted and I took it to a local porsche expert. He called this morning and said the oil leak and cold start issues were minor (temp sensor & oil switch). He checked the car out and found that the transmission case had been sealed w/silcon (red) and not leaking. Some noise that sounds like 5th gear synchros. Also, there are 3 heat shields missing on one head. He thought that the engine should come out, transmission sorted w/ new gasket set, full valve job and new heat shields w/new head studs and fix oil leaks. I was planning on a few hundred dollars and it turns out to be $4500. Engine runs well, a little white smoke on startup (& sometimes a backfire). No blue smoke. Mediocre gas mileage. Temp gauge in city driving is at about 7-8 O'Clock. How important are the heat shields (he seems to think it would be bad to drive it too much) and can they be replace w/out taking the head off?
Thanks

Josh

Josh,

The problems you have stated above could easily be fixed under $200 budget if you could do the work. This will all depend on your ability to DIY and the time to spend doing the task. It is not difficult, it may sound intimidating and nerve wrecking when you do an engine drop or partial drop for the first time. You'll spend more time and a more back breaking work if you try to do this project with the engine in place. To install/remove the air deflectors, you have to remove the CIS unit, alternator, fiberglas shield, etc. and with the engine in place is quite cumbersome and awkward at times.

You need time and a decently spacious work place plus the basic tools needed for the job. Buy the basic tools you will need as you go along doing the project. And it's good to find a 'buddy' or invite a few new friends (Pelicanites) to give some moral support. Ask and you shall receive.

Tony

[my1st911]

Originally Posted by lyonsfin

I spoke w/the shop where I purchased the car and they insist that they did have the head off, replced the head studs, checked the valves, etc and they were fine, and replced with new head gasket. So, I will find out if the heat delectors can be installed without taking the head apart, and, at least, it won't need the studs replaced and a valve job.

The air deflectors should slide in between the cylinders. I wouldn't see any reason to have to take everything all apart