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Re: difficulty starting, barely running Posted by Gary Stottler [Email] ![]() ![]() In Reply to: Re: difficulty starting, barely running, frederickofcolorado, Sun, 15 Sep 2013 12:41:22 Members do not see ads below this line. - Help Keep This Site Online - Signup |
Fred,
I am a bit nervous about the amount of "modification" to the wiring harness that I can see in the photos - it seems that in several places there are cut wires, non-original looking wires, and the red crimp connectors which suggest that in the past someone has attempted to bypass wiring that wasn't working correctly. However, people who leave cut wires dangling usually don't get very good results... The good news is, it sounds like you do have power to the ignition system (if not, it would not start with starting fluid). The bad news is, I suspect you will need to do some patient tracing/repair/replacement of the wiring (which means you will need the wiring diagrams) to get the cold starting system and warm-up regulator system working correctly.
Yes, the fuel line pressure and control pressure can be checked without running the engine, and the basic throttle valve angle can also be set without running the engine. Once those are set and the basic wiring/fuel problems are sorted out it will run well enough to set the ignition timing, the mixture, and the idle speed in that order.
If you have a leak at the warm-up regulator, try removind the two fuel line connections and making sure that the copper sealing washers are present and in good shape (I think there should be 2 copper washers for each line). If fuel is leaking out of the body of the Warm-up regulator then it will have to be replace. They are available (if expensive - $250ish) or can possibly be rebuilt - I think one of our members had some success with that recently although I have never had much luck with that.
I have a feeling you may be going there anyway (new/rebuilt warm-up regulator) because a leading cause of running very lean is the warm-up regulator failing and passing through line pressure as control pressure.
Here's what I can do to help (unfortunately I have back to back business trips this week and next week with a college visit trip this weekend, so it may be Sept 28-29 before I can get this stuff done:
1) Send you a couple of details of the wiring for the cold start injector, thermal time switch, warm up regulator, vacuum impulse contact, etc. so you can trace all those back to their proper source and repair/replace them as needed an make sure you're getting the proper voltage at the proper places at the proper times.
2) Scan/send the stuff in the service manual (unless someone has it already or it's on-line somewhere) related to testing the fuel line pressure and control pressure. Do you have access to the fuel pressure test tool (valve, gauge, connecting hosese)?
3) Ditto the info on adjusting the throttle plate angle.
In the meantime, you may want to carefully inspect and clean the throttle body and check the whole intake manifold and any vacuum hoses for any possible source of vacuum leaks. I would also suggest taking the rubber bellows off the airflow sensor plate and making sure that the plate and the conical part of the sensor a clean and that the plate moves freely (maybe you already did that as part of the injector test). Also, you might take the distributor cap off and confirm that the vacuum advance mechanism in the distributor is working (moves the plate in the bottom of the distributor when you apply vacuum). This is not your main problem, but often these distributors sieze up due to old age and lack of lubrication so that neither the vacuum nor centrifual advance works.
Let us know where you are in Colorado - I seem to remember one or two folks wandering around out there who might be able to remember how this stuff works and might be able to help out if all else fails :-)
Best,
Gary
posted by 198.208.15...
_______________________________________ Gary Stottler
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