Finally got the SC started!!
 

Hi guys,

I changed the 3 easy plugs on the left side of the motor and fixed the vacuum leaks, and was rewarded with a motor that runs, but wont idle without throttle input. The motor has not been run in about 18 months. Its was stil running smokey, going from almost no smoke to allot of smoke and the temp never got out of the first box after running for about 8 min, I need to change the plugs on the right cylinders, and tighten the fan belt.
Can you tell me what the bottom light that illuminates red on the temp/druck pressure gauge is?

Here is a youtube link to the motor running, any suggestions
80 911 sc finally running.mp4 - YouTube

thanks

adam

the warning light is battery/alternator. it could just be because of loose fan belt, or mean alternator is not charging properly.

ok thanks, the belt is loose for sure so will replace it, not knowing its age

if you are going to replace the belt, order the 6 washer you must have for the pulley. You need 6 no more no less. If you have less the nut will bottom out and do very bad things if you have more you wont be able to adjust it the way you need it to.

The idle can be adjusted by the idle set screw on throttle mechanism.

These cars take some time to heat up, at least mine does so 8 min is no surprise. it takes me a good 15 or 20 to get to operating temp.

The smoke is no surprise, its the valve guides if I had to guess. Once you get the car running with the right oil, considering how few miles your car has you should see it burn less smoke as time goes on.

Regards
Dave

All right some progress made! The plug on the right side seem really hard at first especially the front one. but you will get the moves down in time, Folks do remove the AC compressor to do a valve adjustment, but you should be able to do the plugs with it in place. The fan belt is tightened by moving spacer washers from the middle to the out side of the outer part of the pulley. You may want to replace the belt when you take the pulley apart. Have you changed the fuel?
Also have you read about the need to get the engine really warmed up when driving?
These engines don't like to start and just drive a short distance, with all that oil it takes a while to warm up. You may end up doing a couple of laps to do that, Not a bad thing :-) Did you get to drive the car when your Brother had it running?

Cheers Richard

We have not tried to put it in gear yet. Neighbors came home so i decided to call it quits until tomorrow. Will change the other plugs then see what difference it makes. The backfiring had almost disappeared with the occasional maybe every3 or 4 min. I figured it needs to run for a while before i place any judgment on it the smoke.

There is a funny bearing noise, that i think is coming from the fan/alternator, will have to check it out. Just glad to see it run, give me hope going into the clutch change.

Gas is mostly new, i put 5 gallons in and it reads 2/3 tank, how big is the tank?

The noise you are referring to may be the fan rubbing against the outside of the housing. I had this issue for some time, put a new belt on and it was gone.

Regards
Dave

There is a special tool for holding the fan belt pulley to remove the nut that holds the pulley together. Once you get the belt off you can spin the fan to check out the condition of the bearings in the alt.
It is a large tank, around 20 gals.

Cheers Richard

Correction one of my previous posts. According to the owners manual for my 78SC it is 5 washers for the fan pulley. I have also read 6, I cant remember how many I put in, but if the manual says 5 that should be right.

Regards
Dave

Noise from the alternator is a good thing relative to other noises.

21.5 gallon tank size.

Deflect is about 1/2 inch when new belt is installed. Follow the other posts.

You make a real good observation in "once you get the moves down". When you adjust your valves you will be amazed at how adept you feel at the end of the process vs. the front end of the process. I adjust my valves every few years and when I start, I ask myself because of may fat fingers "Should I be doing this?".

Spark plug change out works well for me with two 3/8" socket extensions. One about three-four inches long to clear the engine compartment frame (with rubber filled socket) then another stubby extension about 1 1/2 inches long to allow the socket wrench to fit in the 3/8" drive hole. Still takes almost an hour to change them all with phone calls and self congratulation after each plug install.

Needs a tune-up.......
 

Adam,

Good job!!!!!! Next do the tune-up and tighten that loose heater blower motor. And discard that duct hose on top of the engine. Some TLC and you are ready for the canyon drive. You'll know when you car is in top shape when you start and drive out of your parking spot without waiting for it to warm-up.

Tony

Im actually thinking of pulling off the heaterblower as it never goes below 65 here.
Are the pulley washers reusable, or do I need new ones?

Pretty sure you can reuse pulley washers. As far as gas goes, you added five gallons and it shows 2/3 full, so there was already a lot ofgas in the tank. How old is it? I'd run it out, or drain it, and start with fresh, and Techron or something, to clean the injectors. And really warm it up, eight minutes is not nearly enough. Good luck,

Don Ivey
'87 Carrera

I wasnt sure if the fuel injector cleaners we're safe for CIS. Im assuming there is a drain plug under the tank.

Adam

you can reuse the washers if you wish, you will however most likely find that when you pull them off one or more of the washers will be mangled in some kind of way. If they are not the edges may be rusty or worn out or the washer may have been crushed a bit thinner. Fresh washers are cheap and help to maintain the right distances you need for proper belt installation. Its worth the few dollars to make sure the belt pulley is seated correctly. If the washers dont take up enough space the nut will bottom out on the shaft and mangle the threads.

As for the heater blower, I say pull it. Mine does not even work, ill admit I notice it in the northern winters but I put up with it as I almost never drive the car in the cold any way. It is a lot of dead weight if you will never use it. If you think you may need it one day a year, I'm almost positive there is an adapter that uses the main coolant fan to push some air through the system.

Regards
Dave

Changed the remaining 3 plugs, pulled the heater motor and after checking for refrigerant, decided to pull the a/c compressor. Guess the blower, condenser and related hoses will come out soon.
The motor ran its best almost no smoke and smoothed out allot, just need some time to push it outside and let it run for 20 or 30 min. Almost wants to idle without foot on the throttle.
Interesting observation, it wont start with me giving it some gas, only with my foot off the gas will it start and then i give it a lil bump and it starts running. Im hoping with running it a few more times everything will settle down,and idle on its own, and stop smoking. Then I can proceed to drop the motor and do all the other things on the list. Just want it running satisfactory before i take it apart so i have a reference.

Adam

When you give it gas you are actually giving it air by mechanically opening the throttle plate. An SC in good running order will start with the throttle open but you should not have to do that. Routine starting is with the key only.

Perhaps you have not identified all of the air leaks and by opening the throttle it creates an even more lean a/f ratio.

How does the engine start when stone cold? If you do have unidentified air leaks this should be the time when the engine starts easiest as the WUR is on its most rich setting. As time passes with the key on, battery juice will lean out the WUR even when not running.

If you run the engine for several minutes (not sure exactly how long) , the engine may become warm enough for the cold start valve to no longer function. So you then have leaned out control pressure and no start valve function. Couple this with false air and you have running issues.

On a separate note -

Have you tried adjusting the air bypass adjustment on the drivers side of the throttle body? It is a screw about the size of a dime with a large screwdriver slot. Turning it in cuts off air and out (CCW) adds air. CCW increases RPM and may allow you to let it idle by itself. This probably is not the only issue you have but it may give you a break while you track things down.

I have found that when my car is running well (leak free) I can turn the screw CW and kill the motor when it gets near the end of travel. If I have air leaks, I can't kill the motor.

Back to leaks - You can search for air leaks with starting fluid and if you really want to nail it, use the boyt911SC method and force air into the intake system and see where it leaks out. It's not really Tony's method but he is very thorough. If you are interested I can find some links.

Good job!

Edit - Also look at your plug wires in the dark - real dark with no lights around. Let your eyes adjust for several minutes and look for fireworks around the distributor and wires leading to the plugs.

Stone cold it takes a few tries to get going, 5 or 6, then it starts with no throttle, give it a little throttle, and backfires a few times, runs really rough, then gets going after about 3 or 4 mins of rough idle .
If i leave the key on for 30 sec it starts with a big sure to 2k then shuts down. It starts only when i go straight from key off to ignition and start.
I'm kind of expecting this though since it hasn't been run in while, am i mistaken with this thinking?

I know the air box isnt leaking, as i had smoke coming out of the air flow sensor plate, and out of the pop up when i opened it, but not out of the physical air box.
I plan on changing all the vacuum lines when the motor gets dropped, and doing the leak test as well.

The wires are the original braided bosch wires. i was playing with them and have not been shocked yet.

My 81 has set for 6 months and started in two turns. A little ragged for a few seconds but then ran well.

The vapor observation from the pop off and air flow sensor is not a test. Picture one of your intake runners sucking air past the base gasket. Do you think there will be vapor being forced out of that crack when the airbox is at atmospheric pressure? Not a chance.

The air bypass screw adjusts the air into the system in a very small amount but can impact RPM significantly. I am saying constructively - I do not think you are taking the vacuum leak issue seriously. Vacuum and pressure are the fundamentals of CIS

Edit - also do the dark test on your plug wires. I agree that not getting bit is a good sign they are not in bad condition but humor me.

Can I use the hose from the oil tank to air box be used for the leak test?

Tony looks at these posts later in the evening EST. He can advise in the short term. If I remember one hose ties into the top of the bellows and the other into the oil breather connection. I would not use either of these.

Cold start..........
 

Adam,

Have the engine in neutral, handbrake on or use a wheel chuck to keep the car from rolling. Don't get into the car. Just reach in for the ignition switch and start it. A car that has not been driven for weeks or months might take a second crank. It should start with no assistance from the accelerator. This is not a carburated engine!!!! It is a fuel injected engine that has high fuel pressure in the system.

You have too many unknown variables. Ask yourself why it takes so many attempts to get it started? Is the CSV working? The TTS (thermotime switch) working? Is the control pressure too high? Do I have a significant vacuum leave that prevents ignition? How good is my ignition sparks? And I could add more. The point I'm trying to stress is that you are doing your best but a lot of guess-work is involved. You are doing great!!!!!

You need to know your fuel pressures. And I have not seen anything about your fuel pressures. Second, no significant vacuum/air leak that could affect the mixture. Good ignition spark and correct timing should start the engine at first click.

You have to confirm that you don't have an air leak that could compromise the fuel mixture setting. Not being able to locate or find an obvious air leak/s in your engine does not mean you don't have one. It takes a couple of minutes to do the test. The test is very simple and does not cost you a dime. Air is FREE!!!!! But you need metered air.

Tony

Thanks Tony and Bob,

Im just a bit puzzled, as there was no issues with the car before it was left to get a sun tan for the last year. Clutch issues are the reason it was parked.
I will check for the vacuum leaks and see where it takes me.

EDIT: Does the air filter cover and filter being off have any thing to do with the vacuum system?

Adam

I have spent the past month cleaning up and diagnosing my freshly installed '83sc motor that sat in my garage for over 14 years!

It now runs like a champ!

Air leaks will make you pull your hair out!! They are the number one thing to focus on and you would be surprised where you can find leaks! Spray some carb cleaner anywhere there is a hose or connection between the AIR and the heads and see if your idle jumps! If it does you have a leak!

The next is the fuel system and ign system. If you have not cleaned your fuel system and taken appart and cleaned your AIR, Throttle body and replaced all of your vacume lines you will be fighting an up hill battle.

After doing all of the stuff listed I still had a problem with hot start after running for 45 or more minutes it would just turn over and not start. Turned out to be the Fuel Acumulator! How do I know because some smart person here on the board told me to activate the AIR with the key on by pushing up on the plate for a second and then see if it started...and it did! So I replaced the Acumulator and all is good.

The point is start with the biggest and most obvious (air leaks) and work back to the detail issues.

PS: It starts cold by reaching in the window and turning the key as stated above!!

Youtube Video of the motor running

Good luck!SmileWavy

Thanks for the post Jeff. Your engine sound makes me feel jealous and my 81 is running great.

Adam, I am reading over the thread and you are getting a lot of data. Maybe too much for right now. You know the issue with the fan belt - it is clearly loose from the video. Fix that.

You engine is shaking and making a lot of noises but it is running. Shaking can be caused by misfire and the plugs smoothed that up a bit, right? Bear down on that. The correct test for plug wires is to pull them off and check the ohm resistance - I don't like that test stand alone as the wire can be ok but the shielding poor, allowing spark bleed out before the plug. They arc between wires or where they touch the engine. Back to the dark fireworks test. See with dark adjusted eyes if spark is bleeding out. Your plugs are set to factory gap? If opened up larger (say 45-60 thousandths vs the 30 thousandths factory gap) as can be used with an aftermarket CDI box, that makes it easier for spark to escape.

So far:

Fix the belt and look at the wires in the dark.

Air leaks:

Quick test - If you can get it to idle take the oil fill cap of and see if the RPM's drop. If you can see a 100-200 drop that is good and you are only dealing with small leaks. The oil tank is hooked into the CIS intake vacuum and you lessen the vacuum when the cap is removed and the air sensor drops.

Tony has the most thorough method but I like the carb cleaner as it is the lazy man's way to finding most of the big leaks.

While running spray the carb cleaner on:

- Fuel injectors where they enter the intake runners - rubber o rings in there that get old
- Base of intake runners where they meet the heads - usually just tighten the nuts
- Space ship looking things on the passenger side of the engine where the hoses connect
- Airbox connections for the intake runners - big fat rubber sleeves.
- Airbox connections in back and where it meets the throttle body.
- Pop off valve - some of the carb cleaner will enter the air sensor and impact the idle so try it from different angles.

Try different distances and angles. When you hit a leak you will know.

Obviously, you can have a flash mini explosion if the carb cleaner ignites. Some people use water in a spray bottle and listen for the RPM's to drop - safer. I have never read where someone had the carb cleaner blow up on them (cause they are dead?) so just use your head and don't hog it on. A little spritz in the right place is all it will take.

Air pressure test. Tony says a few minutes but it takes a little longer for me.

My original test in the way back was to duct tape over the entire air cleaner rectangular hole and hose ports on the air box, seal off the oil tank hose from the bellows and seal the exhaust pipe tip (duct tape) . Peirce the duct tape with your air hose tube through the rectangular air filter duct tape cover and give it 5 pounds o' pressure. The duct tape will balloon up a bit. Wet your hands and feel around for leaks. With your hands wet you can feel temp change from the escaping air.

In short:
Fix fan belt
Check for spark leakage
False air (air leaks)

Next chapter - fuel pressure.

You were lucky........
 

Jeff,

You were quite lucky that you guessed correctly. Fuel accumulator is one of the few components that affect residual pressure. FP check valve, WUR, and FD check valve could also contribute to your hot start problem. So replacing a suspected component without verifying or testing it is an expensive way of troubleshooting. It is good to be lucky but you can not depend on luck all the time.

Tony

wow

this guys car sounds A LOT like my car.

Had the fan belt break on me...order the parts from pelican and got the instructions from here as well.

My car has the same issue when starting. Hot weather, it does fine. Recently, I have to give it gas when turning the key. Also noticed oil pressure reads very high for the first 15min.

I'm sure I have a vacuum problems, need to check it out.

replaced my coil, need to try to do spark plugs.

Good luck to the OP, I'll be following.

Sounds so good, didnt want to shut it down
 

Well today was a good day, I brought home the compressor and performed the vacuum leak test and found no leaks! I then drained 2 quarts of oil from the tank, to reduce the large amount of white smoke, and adjusted the screw on the throttle body to help the idle. I now starts on the first crank and idles, and the smoking has been largely reduced. Revs well, and settles back to idle. Once it was at idle i took the cap off oil tank and the revs dropped further proving there is no major vacuum leaks.

I ordered a new fuel filter, no one knows the last time it was changed, the PO had the car for a year and didn't do it. Ordered a new belt and clutch cable as well.

Just want to say thanks for the help you all have given me so far. here is a vid of the start and short run. video 2012 01 30 14 54 28 - YouTube

Adam

Cool. I can hear the alternator making noise. Maybe the belt will help. Keep us posted.

Now go and drive it HARD for about 20-40 minutes and then check the oil level...:=)

If it could drive i would be long gone, but with blown clutch not getting and power transfer. Supposedly the rubber insert blows up and makes the car go now where?

Bummer