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Discussion Starter · #1 ·
So we had a beautiful day here and I cruised downtown ran some errands.. I noticed at the end of the day that at the traffic light the car idled super low so I put in N. Went up and idled softly. Did this twice. And in between it drove super nicely. Then approached a turn and shortly before I came to a stop the engine went off. And I can't restart anymore.. As if I had no gas.. Any idea? Did my fuel pump die? Filter? Or what else can I check.. Guess I have to get her towed 馃槶
 

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Could be fuel pump, ignition coil, weakener solenoid failing. Assuming you have lots of fuel in the tank, have someone turn the ignition on after it has not run for a couple hours while you lay on the ground at the rear of the car and listen for the fuel pump running. If it is then have someone crank the engine over while you check for spark a a plug by pulling one off a plug and holding it with insulated pliers and gloves close to a ground. If good blue spark at a plug then check weakener solenoid operation, remove the float bowl vent hoses from the fuel receiver and see if it will start. Check those things and report back.
 

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Discussion Starter · #3 ·
Thank you very much. So far I tried a couple of more times while waiting for the tow truck. I could smell gas after pumping the pedal. So assume the fuel pump is working?
And I did check the main wire to the distributor cap to get a spark. It did.
That's the situation so far. Tomorrow will try more..
 

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Pumping the gas does nothing on a car with SU carbs as they do not have an accelerator pump. I suspect you may have a failed ignition rotor. Pulling the coil wire out of the distributor cap and holding it close to ground confirms the ignition module is firing the coil and the coil is working but, a failed rotor (and this is a fairly common fault on these) will not distribute that spark out to the cylinders. Try the same test with two or three spark plugs leads pulled off of spark plugs to be sure the rotor is OK. Also, the sparks from the coil lead you did check should have numerous quick sparks in succession, if only one or two then the ignition module has failed. Both a failing ignition module and rotor in these distributors can start to work again when they have cooled down. Both failing rotors and the Lucas OPUS ignition module are common failures on later Shadows. If you have good strong blue regular sparks from a couple plugs leads then it is more likely you have a fuel fault. This could also be a failing weakener solenoid, to test for it pull the carb float bowl vent hoses off of the fuel receiver and leave them open to the atmosphere to test. I'm not sure off the top of my head if your car is equipped with this part if it is a European spec model.
 

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Discussion Starter · #5 ·
How can I check the weakener solenoid operation?
I have the feeling that the problems started when the engine actually was starting to get in the white area of the gage. It stays below the white many times. And today after stopping numerous times and doing stop and go it went into the white. And that's when the rough idling started
 

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Discussion Starter · #8 ·
Gotcha. Copy that. Uk car here

Will do all this tomorrow and hope for the finger. And my bad about the pedaling.
Which brings me to the new question. When the car is parked for more than a day.. 2 or 4 days or longer. It didn't start right away. I thought pumping helped. As it eventually started. I always turned to on and pushed the pedal once to activate the choke. But then when I crank it only starts right away on the same day or next. After a longer period.. It always takes.. Is that already a sign of a dying pump.?
 

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I'm not sure on the home market Shadow II's if the fuel pump only runs when cranking the engine or if it starts running as soon as you turn the ignition on. On NA market II's the pump only runs while engine is cranking so it can take a bit of time to fill the float bowls. UK cars may be the same, in which case that would explain it taking a while to start after sitting idle for more than a day. Try shifting into R and turning the key to start, the engine will not crank over but you should hear the fuel pump run. That is the trick to fill the float bowls before cranking to start. It is not a bad idea though for the engine to make a few revolutions before firing up as it gets some oil under pressure to the rod and main bearings before the load from combustion hits them. It is not a sign of a failing fuel pump. You are correct in setting the choke with a single push of the accelerator.
 

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I'm not sure on the home market Shadow II's if the fuel pump only runs when cranking the engine or if it starts running as soon as you turn the ignition on.
Jim, since I own SRH33576 I can safely say that it begins running as soon as the key is turned to the Run position.

My car was hard to start after sitting for a while when I first owned it and had no idea why. It was because there was no fuel left in the carbs after sitting for several weeks, and I was advised to never attempt to start the car without turning the key to the Run position and listening for the SU pump to stop ticking before I attempted to start it. I did as instructed, and never had an issue with starting the car again.

You can clearly hear the SU pump ticking away until the carbs are primed.
 

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You can easily check via the schematic. Sometimes all terminals are not used, depending on the application. You can easily check to see if there was a prior connection....see if there are marks left by a push on connector.
 

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That is correct, that relay in your picture is used only as an on - off. If the C3 is used it's an on - off - on when used in another application. If you move the gear lever to R or D and turn the key to start do you hear the fuel pump come on? You may have an oil pressure interlock switch which prevents operation of the fuel pump until the engine is running. It has a bypass from the starter circuit, so when you crank the engine over it operates the fuel pump. Once it has some pressure the pressure switch closes so if the engine is running the fuel pump works.
 

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Discussion Starter · #18 ·
That is correct, that relay in your picture is used only as an on - off.....
Thank you Jim. good to know at least there is no wire missing.. I didnt try the R start.. but I disconnected the pressure switch.. then when I turned the key to run I clearly hear the pump.. I tried to start.. but still nothing.. the battery was pretty weak at that point, too.. second try not even the pump would do more than one pump.. will check again tomorrow,. the pump could still be bad even though I hear it now ?
 

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The pump will definitely fail to work when the voltage is low. If it was working OK before it stalled out, it may be that the oil pressure switch failed and that is the only fault. When you get the battery charged up and try to start it again, you should test the pump in place to see if both sides are working. Remove the white wire from one end of the fuel pump, turn on the ignition and see if it pumps, then reattach that wire and remove the white wire from the other end and check for pumping. Often one end of the pump will fail and the car will run on just the other end until it fails leaving one stranded. It's a good idea to do this check at every service to lessen he chance of a complete failure on the road.
 
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