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CMXXXI · Joined: 05 Nov 2002 Posts: 1939 Location: Vicksburg, MS

Does the metering plate balance "just so"? It should just about deflect if you blow on it hard (well, maybe really hard). If it is sticking and/or binding, your manual tests will say that fuel is getting all the way to the cylinders, but under actual operating conditions the plate may be stuck closed.

Can you get the motor to start/run using a can of spray ether starting fluid? If it'll fire and you can get it to sustain life by spraying into the air flow metering box while playing with the throttle body, then you've definately narrowed it to a fuel delivery problem.

Have you put the CIS gauge on and tested system, and control pressure (hot and cold)?

...just more rambling thoughts...
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'79 Eurospec 931

Jazzerpet · Joined: 07 Apr 2003 Posts: 186 Location: Omaha, NE.

The procedure I was referring to is on page 25-15 of the turbo factory manual. The sensor plate is adjusted correctly. Apparently I did not make the initial adjustment correctly. The book tells me to take a line off the dizzy, I did, what I thought was fuel level with the top of the outlet was apparently not the case. What I did this time was remove all the injectors and place them in a container. I then ran the pump via pin #7. All the injectors spayed fuel. I tried to adjust the screw to stop them from spraying they would not. The screw bottomed out and the injectors still spayed fuel. The book mentions shims I believe they go between the dizzy and the air control sensor. Could it be I need these? BTW when the metering plate is depressed the spray increases. I have not bought a CIS pressure tester yet.
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1980 931
1985 ½ 944
Member of the “Omaha Crew”

Smoothie · Posted: Fri Feb 20, 2004 11:38 am Post subject:

CMXXXI · Joined: 05 Nov 2002 Posts: 1939 Location: Vicksburg, MS

Yep, you gotta get them injectors to shut completely off when the plate is in the "at rest" position (adjustment procedures on Pg 25-8). You are definately on the right track though. And, like Smoothie says, clockwise makes it rich (Pg 25-7), and the only shims involved are used in adjusting the system pressure (Pg 25-8 of the "base" manual).
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'79 Eurospec 931

Jazzerpet · Joined: 07 Apr 2003 Posts: 186 Location: Omaha, NE.

Well they will not shut off. Two spray a lot and two spray a tiny bit. I have adjusted it all the way down. Bad dizzy? Pressure regulator would not come into play here would it? On an upbeat note I got the 77 running and driving, the clutch slips a bit but I finally after a year and a half made a 924 run.
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1980 931
1985 ½ 944
Member of the “Omaha Crew”

CMXXXI · Joined: 05 Nov 2002 Posts: 1939 Location: Vicksburg, MS

If the injectors are always spraying you'll never get the mixture right. Perhaps the control plunger is sticking. It's time to buy the CIS test gauge and hoses. If the contol pressure is too low it'll cause an "always rich" condition and also prevent the injectors from shutting off all the way.
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'79 Eurospec 931

-nick · Joined: 16 Nov 2002 Posts: 2699 Location: Cambridge, MA

When I was playing with mine I found that the two armature pieces that are supposed to move relative to each to change the mix were very tight. For instance, when I adjusted the mix lean I had to press down on the airflow plate to get it to "seat" on the mixture screw.

That probably doens't make any sense, but try leaning the screw all the way out then press down on the airflow plate until it stops then give a little more pressure. I bet it will move down a bit more which will lean it out until it comes to rest on the mixture screw. I tried to loosen mine up by opening up the assembly and spraying some penetrating lube around the pivot. After working it back and forth it still stayed really tight.

-nick

Jazzerpet · Joined: 07 Apr 2003 Posts: 186 Location: Omaha, NE.

I did order the CIS pressure tester from JC Whitney. That is how I got the 77 running. I will check the control pressure tonight. I don’t think the plunger is sticking. I recently replaced the air control sensor. The piston moved smoothly in and out of the fuel distributor. I also cleaned the assembly up everything is moving free. I also set the sensor plate for center and Height.
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1980 931
1985 ½ 944
Member of the “Omaha Crew”

-nick · Joined: 16 Nov 2002 Posts: 2699 Location: Cambridge, MA

You're not being very cooperative

If you come to a grinding halt, I should have an extra whole fuel dizzy/metering assemble available shortly.

-nick

Jazzerpet · Joined: 07 Apr 2003 Posts: 186 Location: Omaha, NE.

Well I am only trying to be thorough.

_________________
1980 931
1985 ½ 944
Member of the “Omaha Crew”