Only runs for 30 sec...

[esquivelia]

Wow! I didn't see this had gone to a second page. All of your suggestions seem very much worth trying out. I will try a few this weekend.

Just to recap: Rebuilt Weber carb, new replica pump; the glass bowl type, new fuel filter.

Thanks again for all the input..will report back!

[esquivelia]

Still no results...next step, electric fuel pump. I'm going to mount it close to the fuel tank with an inline filter just before the pump. Probably pick one up at Pep Boys. If anyone has any suggestions for me fire away. I saw that they had a few models there. I'm not sure what I should be looking for as far as the specs of the fuel pump.

Both fuel pumps (the old one and the new one) move fuel when I manually pump them either with the priming lever or the actual arm. This leads me to believe that maybe I have a worn lobe on the cam shaft.

Thanks! Cory-

[esquivelia]

also...I haven't even thought about wiring the fuel pump. Not sure where to tap into.

[albersj51]

Ill try digging up my part number for you. I ran it off of the ignition so that it comes on when I turn the key.

[I Leak Oil]

Napa used to carry a relay that you could use to tap into the oil pressure idiot light. That way if you're in an accident the pump will shut off when the motor does. Even if you don't use something like this run a dedicated fused circuit.

[SafeAirOne]

In the 109 6-cylinders, they ran the factory electric boost pump right off the white primary wire for the coil.

I seriously doubt that the cam lobe for the fuel pump is worn out. Do you realize what it would take to wear it down to an extent that the pump becomes ineffective? You'd have to have play sand in the oil or a cutting edge on the pump lever for that to happen IMHO. I'd suggest you look elsewhere for the cause of your fuel supply, personally...

[Sputnicker]

I did a pretty thorough web search on electric pumps and decided to use the Facet Posi-Flo. They are available at NAPA. Get the lower pressure version (1-4 PSI). Here's a link:

http://www.facet-purolator.com/images/technology/hd_pdfs/Posi-Flo_sheet.pdf

[Wander]

That's the one-low pressure pump should be about $50. Mine is directly down line from the tank and mounted on the seat box front wall. I'm not crazy about this spot as it is just above the tranny and transfer case so if I had a leak it could get ugly. I've seen others place it along the frame rail.

Mine is wired wih the ignition-turn the key and you can hear it pumping away. Having the return line will be great with an e-pump and a webber. You'll need a filter with a bypass to run the return line from. This will help you avoid vapor lock and dieseling aftger shut down when it's warm out. The new fuels with the alcohol don't burn off as much and so I get dieseling after shut down as I don't have a return line to the tank.

[kevkon]

I seriously doubt that the cam lobe for the fuel pump is worn out. Do you realize what it would take to wear it down to an extent that the pump becomes ineffective? You'd have to have play sand in the oil or a cutting edge on the pump lever for that to happen IMHO. I'd suggest you look elsewhere for the cause of your fuel supply, personally...

X2
I doubt it too. I know that many have had issues with some of the replacement mech. pumps, but there should be no reason why a properly functioning one can't do the job. Especially since these carbs don't need much fuel and don't like much pressure.

[Apis Mellifera]

I wouldn't rule out a worn cam. Anyone who has taken apart an MGB engine will likely have found a very worn cam. I've seen lobes basically worn round. That said, it's a gradual problem. What specifically has changed since the truck last ran well?

I have the above Facet pump on my MGB and while it works well, it makes a continuous audible buzz. For this reason, I do not care for the pump despite the fact that it works well. I would recommend an SU fuel pump or the replacement mentioned here:

http://www.mgexperience.net/phorum/read.php?1,1638176

Facet pumps are also discussed.

[bobzinak]

not passing gas

I too had a problem with a new fuel pump. worked like a champ when I first rut it on, but over a period of weeks my power and top speed started dropping. to the point where it would barely run. turned out that one of the small one way valves was shut and no amount of fiddling would let work. a proper fuel pump should develop a good amount of both suction and pressure. if you have the pump off the suction side should hold your finger, in the inlet, the pressure side push air out around you finger. it seems to me that if you can run it with the manual primer says that your not getting enough fuel. I had one pump that had a bad valve an the fuel would bleed out of the line when it sat for awhile. also make sure that the two small flat wedges that hold the pump pivot pie are properly peened in place.I don't think the problem is in the camshaft. and unfortunately even the best parts can have defects. Hope this helps. bobzinak.

[cousindave]

I have had the facet pump and now I have a mr gasket pump. Both are great pumps! Went mr. Gasket when facet died after 8 years of sucking rust through the pump with no filter or screen to the pump. Don't forget to get a pressure regulator and relay while you're at it.

[gudjeon]

I tried the mechanical and had 2 fail to work from new. I had it and went to an electric from Napa and created my own recirculating system. No more vapour lock. It keeps the fuel constantly moving, filtered, and under pressure right up to where it needs to be. Modern fuels are made for high pressure injection and are not suited for carbs. New fuel is more volatile in an open carb system and gets worse with heat and altitude. I used a lower pressure pump from Napa (made for carbs) and a recirc filter from 1980 Chrysler spec. I did not even worry about mounting it low and it work just fine.

P.S. its on the bulkhead.

it ain't pretty, but it works pretty good.