83 sc backfires won't run help please

[boyt911sc]

Michael,

Your WUR is out of spec. right from the beginning of the test. WUR-090 is one of the most tedious WUR to test and calibrate. This WUR needs some testing and calibration to make your engine run good. The problem would be at cold condition. Your current WUR has no cold condition and goes straight to warmed condition. That's the reason your engine struggle to run correctly. You need a good working WUR-090 if you expect to have a good running engine. Keep us posted.

Tony

[roadster49]

Update:

So on Mother's Day, my kind wife allowed me to drop the engine again. The three screws holding the FD were frozen but with some persuasion I was able to free them.



Here are pictures of the WUR and the FD.






Note the plunger on the FD is frozen.

Next steps to check fuel lines and gas tank.

[boyt911sc]

Michael,

The package containing the FD and WUR arrived today. I had a scheduled run for WUR's today and yours came just in time for the evening run. Unfortunately, the test showed blockage at WUR's inlet port causing excessively control fuel pressure. It would take some effort to clear the rust and other debris on the micro mesh.

Second, the FD plunger is stuck as you had indicated earlier. I will get to it tomorrow and update of the result of the tests. For the meantime, check the return line to the tank and might as well clean your gas tank.

Tony

[I FROGGY 944]

i am getting tired of this beast, must be a flow chart and a diagram of the components with explanation of their function so you can do a systematic test with out going in circle,will try to draw one up

[roadster49]

Update. It now runs! What I found - the brake booster Hoses were leaking, their was no gasket on the oil cap, and air leaks that I was able to find with a smoke machine.

Work completed included - new gas tank, Tony rebuilt the FD and WUR, new air box, distributor cap, braided wires, plugs, hoses.

It was a long journey but it runs and am hoping that continues.

Roadster

[Ruby1983-911sc]

WoW! I read the entire thread and am blown away with your patience. Congrats to you Michael for all your efforts. For me it is exactly what I needed. It pays to pursue the issues at hand. I am having issues with starting my car. I am reviewing all I can and will attempt finding my problems. Thanks to the guys, Tony and Bob. I appreciate the input. Happy for you.