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LONG TIME SINCE I'VE BEEN HERE.so please be gentle

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Blackjokr

Jedi Warrior
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ok so I bought a 1978 MGB from a guy in Florida. Car was a daily driver and worked fine. I took it out then put a full tank of gas in it and I put it away in the garage for a 2 years. I turned it one a few times and it probably sat for more than 8 months not turned on. anyway, new battery and car would not turn on. it tried so I checked th fuel filter and it ws dry as a bone. it was a modern see through filter. Closer look and it was brown from what looked like rusty gas. So tried to start it again and unhooked the lin kfrom the filter. No gas. Opened the fuel tank and gas shot out like a small cannon...(back pressure). So I figured it was clogged and probably time the original 40+ yr old tank got replaced. Did that without too much effort. Gas was dark yellow, brown..gross! Called Moss motors, new tank, new electronic fuel pump, new sender. Anyway, now even after replacement and 5 gallons of gas in the tank i am still starviing for gas. Fuel gauge shows about 1/3 full. I used a voltmeter and ofund power coming to the fuel filter. it's an oem but electronic instead of points. So do you think it is possible that it is clogged somewhere after the fuel pump? I did realize that when i bought the new pump that I had to remove the two (forgive my ignorance) bolts which have the valved in them and move them to the new pump. I checked to make sure the valves opening were in line with the hoses, but maybe they moved when i installed? They seemed on because when i blew into them i heard/felt air come out the other side. I am assuming it is beyond the fuel pump. If that is the case, then shouldn;t the line TO the pump still be wet> Because as of now it s bone dry as if gas is not even leaving the tank to the pump. help. thanks and sorry for my ignorance!
BJ
 
i noticed also that there is a clear colored liquid that is slightly thick..i do not thin kit is water and it si not gas because it doesn't smell like it kinda pooling a litlle under the middle of the car after i jacked up the rear tires
 
Any chance someone added another in-line filter coming out of the gas tank?
 
Basil!! wow..long time no speak. Do you mean a filter possibly under the car? the one I replaced was under the hood right before the carburator. I see the line to the pump has no filter, but was a bit nervous to crawl any more under the car. teh back is lifted on floor jacks with its @$$ in the air...jacks under the springs(?)....the metal bars that run front to back on top of each other..

BJ
 
i guess they are called the struts!?
 
You might try blowing out the fuel line with some low pressure air from your compressor, etc. disconnect the line at the carbs and the fuel pump and see if any crud gets blown out. Then repeat for the section between the pump and the tank. It's also possible one of the rubber hoses is collapsing internally, blocking the flow.
 
With the gas we have nowadays and the car sitting for so long, your probably going to have to replace the main fuel lines. The gas will have jelled and clogged the line. I've done this job at least 4 times this last year on TR4's and TR6s. Its worth a try with the compressed air but it won't get the build up of goo on the inside walls of the line.

Marv
 
Do the blow out from front to back in several stages, carb inlet to disconnected fuel pump outlet, then disconnected fuel pump inlet to disconnected tank outlet, then tank outlet into tank.
Bob
 
bobhustead said:
Do the blow out from front to back in several stages, carb inlet to disconnected fuel pump outlet, then disconnected fuel pump inlet to disconnected tank outlet, then tank outlet into tank.
Bob
Click to expand...

Agreed! :smile: I just didn't break it down that far. That method will help identify which portion(s) are blocked...if any.
 
you guys rock! THANK YO UALL SO MUCH FOR YOUR INFO! The tech At Moss Motors suggested a similar approach so I just bought a gun for my compressor. The tank and pump are brand spankety new with bran dnew gas installed 2 days ago so I am thinking htat should be ok. I think I am going to replace all of the lines. Anyone have an opinion of braided hoses over standard rubber line? Let me try your suggestions then post the results. Again THANK YOU ALL YOU ROCK!

beest,
BJ
 
ok a little update: So I blew out the lines and everything is nice and clear. Some old gas came out between the front of the carb blowing towards the back and the hose that would be on the OUTbound side of the fuel pump (I dsconnected it and put it into a bucket. hooked all back up and still no fuel to the carb or even before it. So I took the fuel pump out and hooked it directly to the battery..BAM it began pumping (well its new so i expected that.) Hooked it back up and NOTHING when i turned the key and tried to start the car. Mind you it did work less than two years ago. No hoses..nothing..just hooked to the hot wire that it connects to in the trunk. It is a solid white wire that goes under the car and I am assuming winds up in the engine compartment somewhere. I tried to find it but am not sure where to look. Anyway, I hooked a voltmeter to the feed wire and turned the key and instant 12 volts. Turned it back off anf nada. So how the heck can i be getting the voltage and the darn thing won't pump when I turn the key?? ARGH!! My old pump had the spade lug on the fuel pump with a splitter on it so that the hot wire and a wire with a spade lug to ground were on it (it grouned to the car). I hooked that back up and same problem. I don't want to quit but this is blowing my mind. How can this be? Any insight fellas?
as always, thanks in adavcem for your expertise!!
 
so i found a wiring diagram and then the inertia switch which it connect to. I find a sticker under the steering wheel by the inertia switch which reads "Plunger must be fully depressed for fuel pump to operate". Where the heck is the plunger and how do i depress it??!!!!! Coudl this be my darn problem???
 
ok so i reached under and found the plunger and it is as down as it will go. I can lift it up, but then push it down and it looks almost like a toothpaste cap and it sits about 3/4 inch from the top of the casing. So, all back togther and still no starting. grrr....no fuel makes the MGB a thirsty boy!! Could the inertia switch be bad? is there a bypass test?
 
Blackjokr said:
My old pump had the spade lug on the fuel pump with a splitter on it so that the hot wire and a wire with a spade lug to ground were on it (it grouned to the car). I hooked that back up and same problem. I don't want to quit but this is blowing my mind. How can this be? Any insight fellas?
as always, thanks in adavcem for your expertise!!
Click to expand...

OK, so if the pump works when it's not installed, and you have power all the way to the pump, my money's on grounding problem. How did you hook the pump up when it was out of the car? If the pump's supposed to ground to the car, and if you have the pump mounted in a rubber sleeve, it won't ground properly without a dedicated ground wire. And I'm not sure I follow the "splitter" you mention. The way you describe it sounds like the hot and ground are at the same terminal.
 
Mickey,

Thanks for the response! that is exactly right. Basically, the spade lug had another spade lug on it but it made one lug into two. Kind of like plugging a multiplug into one electrical socket. And so yes it is in the rubber sleeve. Then the ground and the hot wire do come off the same spade lug. the hot wire goes to one of these "splitters" and another very short wire with a forked lug on the end is grounded to the car off the other splitter. I thought that's bizarre because thye both come off the same spade lug. The weird thiing is the old pump (which was points and not electronic) worked this way. So if I remove the short wire that is grounded to the car, remove the splitter and just hook it direct to the hot wire it does not run either. So, if it is the ground, how do I ground it? I am guessing I am supposed to use the other spade lug to the actual body of the car? Again, this was not used previously and according to Moss Motors tech it should only require the feed wire. Maybe I am missing a grounding bracket or something? The only thing holdiing it in is the rubber sleeve with an o clamp bracket that squeeezes the sleeve around it. Hope that makes sense!

Now the way I hooked it up out of the car is i ran a wire from + on the battery to the spade lug for the hot wire. Then I ran a wire from the - on the battery to the other spage lug (the one that would actually be under the car and NOT in the trunk. Pumped like a mofo after that.
 
If you have 12V all the way to the pump, then I'd run a separate ground wire from the ground connection on the pump to the chassis.
 
and a dumb question When does the pump kick in? When I turn the key o power is to the car or only when i have the key turned to full ignition? If it is a gorund problem I could get under the car, hook a ground wire to the pump and find some metal to ground it to.
 
The pump should come on when you turn the key to "On"; next key position energizes the starter, and the pump should already be working.
 
I guess that answered that question, Mickey..lol..thank you I will try it. Are they normally grounded to wotk? I ask only because the Moss Motors tech said you don;t need it, but I can't imagine that you don't. Not sure how many electrical devices can run with just a hot wire. How else would it complete the circuit?! Do you know if typically the electronic pumps require the ground on the other lug? I even asked th MM tech why do they have a separate lug which looks like it is ground if you don't need it? I am assuming there used to be some sort of metal bracket the pump was attached to that grounded it automatically then thy put the rubber sleeve and required a separate wire?
 
these forums are like having your own team of experts and awesome dudes! thanks I'll give it a shot and post back.
 
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