924Board.org

CaptainTornSack · Joined: 25 Jul 2020 Posts: 10 Location: Eugene, Oregon

1977 Porsche 924. Long story short. Car was running but rough but would spin the tires. Leaked fuel in air filter housing then flooded the engine with fuel...literally. Had to change my brand new oil and filter. Pulled distributor apart and found 2 1/2 o-rings. Ordered rebuild kit. Cleaned and reassembled. Consistent injector output. Great spark. No start. Just turns and turns. After much digging, I feel inclined to believe the adjustment screw is waaaaay off. I have no reference to a properly functioning engine. Any experienced thoughts? Until then. I'll just keep twisting... 1/4 turn at a time. Maybe I'll get lucky. BTW. This is my first German, grew up on American.

Rasta Monsta · Joined: 12 Jul 2006 Posts: 11723 Location: PacNW

I wonder if it would fire on starting fluid with fuel fuse removed.

Crazy idea but fuel wash might have caused loss of compression if rings are badly worn. Try oiling the cylinders through the spark plug holes.
_________________
Toofah King Bad

WeiBe (1987 924S 2.5t) - 931 S3

emoore924 · Joined: 13 Apr 2004 Posts: 2815

It has been a really long time since I messed with CIS so take the following with a grain of salt.

IIRC there is a way to get to an "in the ballpark" starting baseline setting by closing the screw all the way (gently), then removing one of the distribution lines, and with the fuel pump on, you adjust the screw so that when you just barely lift the air metering plate - the fuel just starts to flow. Replace the line and try to start the car.

That should let you start the car and it should idle/run. Then you tune from there with a HC/CO meter.

Since you're messing with fuel, do a search and make sure this procedure is correct. I think is had been documented somewhere...

anthonimartini · Joined: 17 Feb 2020 Posts: 240 Location: portland oregon

emoore, that is the correct way to get it into a good baseline, usually extremely lean but can be manipulated into running enough to tune. i do this when i rebuild the metering units.
_________________
ive saved alot of 924's
current:
79 MochaSchwartz 931
83 944
87 924S
Instagram @anthoni.jpeg
formerly known as turbellion, lost password.

CaptainTornSack · Joined: 25 Jul 2020 Posts: 10 Location: Eugene, Oregon

Update. First rented a compression tester. Unfortunately, this tester was never designed for these spaces. That was a no go. So I decided to establish that baseline. Bottled the injectors, and noticed #1 sprays an aerosol at baseline, or close to it, while 2,3,and 4 trickle. Yet, at 1/4 throttle, they spray nice enough. Solution, ordered new injectors. They'll be here Friday. I'll reset the baseline then, squirt some oil in the cylinders, throw the plugs in, and give her a go. Meanwhile, I'll search for a suitable compression tester. Maybe a leak down as well. Sadly, I'm fairly confident the valves are shot. When I got the car, it was, unbelievably, running on two cylinders. Guy had plugs 90 degrees off counterclockwise. It freaking ran! I had an overheating problem, so replaced the water pump, timing belt, tensioner, and thermostat first. System flush included. Started playing with idle adjuster and fuel mixture (she was stupid rich), and discovered the plug wires. Corrected and got her to spin tires. Replaced/regreased rear bearings. Suddenly, charging issues. The alternator exciter circuit was not functioning. Semicorrected that problem, meaning I have managed to get everything functioning for starting and operation except the fuel guage. No, as far as my meters can tell, this is not the problem. She tried to start, but all but 2 o-rings disintegrated in the fuel distributor. Rebuilt it and started pressure tests. Dizzy is great. Warm up regulator is struggling. Not done, but near future replacement. Thank all of you for your thoughts. I believe the baseline suggested helped me identify another problem. Although, it is a logical problem. The rubber had to go somewhere. With all of that said, I'll give an update Friday evening. Who knows, she might fire right up.

safe · Joined: 18 Mar 2017 Posts: 586 Location: Sweden

Starter fluid, to see if it fires when it has something that will burn.

The usual, check for crap in the fuel, fresh fuel filter...
_________________
/Magnus, Stockholm Sweden
=======================
Porsche 924 -79 NA, EFI and Turbo.
Porsche 931 -79
Porsche 911 -77, 3.2 Targa
Porsche 911 -69, 3.6, Coupe

Rasta Monsta · Joined: 12 Jul 2006 Posts: 11723 Location: PacNW

kabok · Joined: 25 Jan 2003 Posts: 179 Location: Ft. Collins, CO

Take the air filter off. While someone is cranking the starter, reach in and push up the air metering plate. See if you can hear the fuel pump working. If not take the electrical switch going to the air metering plate. Try again.

CaptainTornSack · Joined: 25 Jul 2020 Posts: 10 Location: Eugene, Oregon

So she got new injectors today. Reset baseline. Much more appealing btw. Reinstalled plugs. Added just a little oil to each cylinder ( through injector port). Turned the key. She blew the intake line off the metering unit. Reattached more firmly. Tried again. Same result. Conclusion. Intake valve (or 2) is stuck open. Guess I'm pulling the head. Please someone stop me. You know I won't stop there. She'll get new rings as well. No point in not doing it. Funny part is, I'll have to do it all in the engine bay. I don't have a hoist or stand. Guess I'll dig up a helper.

safe · Joined: 18 Mar 2017 Posts: 586 Location: Sweden

CaptainTornSack · Joined: 25 Jul 2020 Posts: 10 Location: Eugene, Oregon

Shouldn't be a possible problem. Replaced timing belt. She spun the tires. Everything was on point. Probably why the dizzy failed critically. Remember, I purchased her firing on 2 cylinders on the intake stroke. That causes valve damage. And a Petro flush to the equation and I can conclude all kinds of head problems.

CaptainTornSack · Joined: 25 Jul 2020 Posts: 10 Location: Eugene, Oregon

Read that they'll cough if too lean. Gonna richen the mixture.

emoore924 · Joined: 13 Apr 2004 Posts: 2815

Ok, dumb suggestion, but check that your firing order is correct. Could be firing out through the intake.

A compression test will indicate a stuck or bent valve, among other things. Or you could pull off the valve cover and you might see one of the valves remaining extended (valve spring and follower remain compressed) even when the cam lobe is facing up (check for excessive valve lash...).

In my experience, it would be unusual for a non-turbo to bend a valve but I guess it happens every now and then.

safe · Joined: 18 Mar 2017 Posts: 586 Location: Sweden

CaptainTornSack · Joined: 25 Jul 2020 Posts: 10 Location: Eugene, Oregon

Update. Timing is great. Spark is nice. Fuel delivery is great. No, still have not found a compression tester that I could get to hook up. Work space is quite restricted. Maybe I should just pop the exhaust manifold off for access? Regardless, fuel(yes I tried starting fluid to no avail), air, and spark. She'll blow the intake off if to lean, but nothing otherwise. Thinking about breaking seals tonight. Full gasket set from headgasket up is $80. Cost me more to buy a decent compression tester, leakdown guage, and air compressor. Which could lead to pulling the head anyway. I really don't want to but can't come to any other logical conclusion. Seems this girl won't run unless I fix every flaw. Does she love me or hate me?