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MGB Stalling and then restarting after 4-5 minutes

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I wonder what that gelatinous mass could have been from?
 
It wasn't really a "mass", at least when I found it. It was small pieces that would come out with each successive flush, they would dry up and shrivel down to a 1/10 of their original size. Could have easily been a part of a larger mass inside the tank, but without a camera I had no way of seeing that. I put in about 4 oz. of Marvel Mystery oil with each fill-up and winter her with a full tank and dry gas and Re-Stor from Moss. Had the consistency of wet silicone, could have come from a seal that was done with silicone, but I have no idea where you would use that. I replaced the sending unit a couple years back, none then and I sure didn't use any. This stalling issue is new to this year.
 
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"I also changed the fuel filter and upon opening the fanned filter found a lot of grit for lack of a better word."

I hope that filter is not between the tank and the pump. If it is, each time it becomes clogged, it will cause the pump to stall in a current on condition, resulting in an over heated pump, unless the power is shut off. Any aftermarket filter between the tank and the carburetors, it should be after the pump, thereby stalling the pump in a current off condition. This may be a mote issue at this point as the clog could very well be on the screen on the pickup tube in the tank, even though it is a fairly course screen.
Cheers,
 
The fuel filter is just before the carbs. I am leaning toward the relay being the problem since it has been buzzing. I've never had a relay fail before so I'm not that familiar with their habits, but the buzzing would seem to be an indicator of pending failure, especially since it is affected by wiggling the relay. The same stalling results would happen if the intake were plugged or the pump stopped pumping (due to relay failure) and was no evidence of the gelatin in the old fuel filter, and some would have certainly passed through a coarse filter as the pieces were of all sizes. if a new relay doesn't work I'm considering blowing out the intake line to clear the filter face. I'm not at all familiar with the intake setup, I assume I should use lowest pressure possible and this will lead again to draining the tank to remove debris.
 
Just pull the line from the pump's output side then push air back thru the line the filter is connected to. If the car runs okay between stalls the carbs are likely fine.

Replace the relay first tho. It sounds 'ropey' to me.
 
I've had a couple of cases kick me around this last year, with symptoms resembling vapor lock. (stalls hot, restarts after cool down.) With both cars the faulty part was an ignition condenser in the distributor. Although spark appeared OK, apparently it was somewhat intermittent. One vehicle was a TR-4, the other an early seventies Mustang II.
Hope this helps.
 
Dave, I can't get the car started. I have fuel in the filter located immediately in front of the carbs, it is about 2/3 full. The pump does not click when the key is turned on, and it also seems that the carbs aren't calling for fuel. Does the pump need to "push" fuel to the carbs? I can't see how that would be right but the coincidence of the pump not starting and the carbs not drawing the fuel out of the filter seems too convenient. I have given the pump a few raps with a light hammer but no change. Any thoughts? BTW the fuse and relay are good. I plan to send the pump to you over the winter for a rebuild or check up, but need to drive the car to winter storage.
Thanks,
Mike
 
Mike, as of right now, are you getting spark at the plugs? In other words, when it refuses to start, or stops running, have you checked the plugs for firing?
Does the fuel pump sound different when the engine shuts off?
After driving our 72 for a year, we took it out for a run and it ran for about 5 minutes and quit, I could shut the ignition off, turn it back on, the pump ran then stopped normally, we took off and it did it again. The problem was an air leak in the line coming from the tank to the pump. It was cracked inside the metal covering. PJ
 
Hi Paul, I'll check the plugs in the morning. I changed them a few weeks ago even though the existing plugs were that nice cocoa color, but they were three years old. The pump makes no sound at all, no clicking at all.
 
Use your shoe and give the pump a whack, if it starts, where your problem is, is solved.

Wayne
 
Problem found and solved. One of the tangs on the fuel pump relay had been pushed in just enough that I wasn't getting good contact. Way back my wife had pointed out that it always seemed to stall after we hit a big bump, I discounted that at first as she is always enjoying the scenery while I'm enjoying the road, so she never sees any bumps coming regardless of size so they're all "big", as are all spiders. Now looking back it could have been the case all along, I'll be sure to tell her she was right (no, really) although it could have been something else, I think maybe the rear bumper bearing was twisted. Thanks for all the input, and kudos to Doc and pdplot for being right about electrical and relay related. I'm still somewhat concerned about the restarting issue, although someone told me that the poor connection could cause heat and that as it cooled I was able to get enough of a connection to start again. Once I pushed the tang back up into the receptacle the pump started pumping and she turned over fine. Haven't taken it for a ride as I'm putting it away for the winter today. I wish I had thought to only turn the key enough to start the pump when attempting a restart after a stall, that would have told me right there that the problem was pump related and I would have avoided having to drain and clean the tank, but now it's shiny in there!
 
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