QuestionQUESTION: Dear Mr. Fitzcharles
You recently solved my TR7 high idle issue,"The stuck temp bulb" Thank you again, car was running fine until the other day when she would not start. Acted as if no gas, checked and confirmed fuel supply to carbs, both have positive pressure to inlets. Sprayed some starting fluid in and it started immediately. It ran for approximately 3 - 4 seconds and stalled. Next, I put some gas in a squeeze bottle, dripped it in front of the 2 air valves, and I can run and accelerate as long as I provide fuel. I just changed my diaphragms and re-balanced the carbs and backed off the Idle screws and gave them 1 and 1/2 turn starting point. Still would not start on its own, I don't believe both floats or needle valves could have failed at the same time, so I haven't addressed them, I'm confused.
I tried to find some literature on the Stromberg 175 CD-2 series but no luck. Before I go any further on my own, I decided to ask for your expert opinion again. Any suggestions or directions are truly appreciated.
Sincerely;
Rich
ANSWER: Hi Rich,
It sounds like there is no fuel in the float chambers. Or you have a vacuum applied to the float chamber vent hoses. First remove both vent hoses and allow the float chambers to vent. Then spray fuel into the intake to get the engine to run and if the engine continues to run ok, look at your charcoal canister and the anti dieseling valve next to the canister and check for any raw fuel in any of the vapor lines or in the canister. Remove the vacuum hose from the canister and plug the hose.
If none of this is wrong you need to remove the carburetors and check the floats and needles and seats and the float levels (17mm)
Howard
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QUESTION: Followed the procedure you outlined and was not able to start on its own. being curious I removed the diaphragm and inserted a tooth pick down the jet, and confirmed the presence of fuel in both carbs. The next thing I did was put positive pressure on the float chamber vent lines and forced some fuel out of the jets, effectively dropping the floats. My next attempted start was rough, but successful. I re-assembled everything and am only able to start with the idle mixture screws drawn all the way out and increasing the speed. Another observation is when I block the intakes the engine accelerates and runs smoother.
Before I continue do you have a source that describes the proper set-up procedures for the 175 CD-2, because I'm only remembering and modifying my 75 TR7 procedure. I would like to be more familiar with mine so I can work more intelligently with you. I have not been successful with my search. Thank you in advanced for all your help and tolerance.
Sincerely;
Rich
AnswerRich, I think you found your problem when you restricted the air intake and it smoothed out.
That is a standard test procedure for checking for a vacuum leak. When it is idling and you slowly start restricting the air intake and it ant any time smoothes out or speeds up it is a sure sign of a vacuum leak somewhere. Our next step is to start pinching off each hose to see if you can duplicate the smooth out. If not you should try squirting oil or some other fluid around the intake manifold and carb mounts. It is difficult to get it up under the manifold so some mechanics use raw propane since that will get to the under side of the manifold. If you do this, you need to be prepared if there is a spark that can ignite the propane.
Haynes has a Stromberg carburetor book that covers overhaul and adjustment of Strombergs. You may even be able to order it through a book store by it's ISBN # 0 85696 300 3 or order it from Haynes.
I use the same method I use on twin SU carburetors except the jet adjustment on Strombergs is with a 3mm Allen wrench down through the top pot. Clockwise for rich and counter clockwise for leaner.
Read my web page on adjusting SUs at http://mg-tri-jag.net/tech16.htm
Howard
