Gettin' ready to put an electric fuel pump on the Stude but I want to keep the look of the old mechanical pump and fuel lines under the hood as eventually I will go back to a more traditional carb set up than the Performer on it now. Has anyone ever gutted a mechanical pump and set it up so the fuel just p***es through? Would I need to connect the inlet and outlet internally. The arm would be removed and I would have a blockoff between the pump and engine so no gas would get into the crankcase. Comments? Criticisms? Howls of derisive laughter?
On most you can just disable the arm. Set up your electric pump as a pusher and the gas will flow right thru your 'dummy' pump no problem.
Ummm You could just use the mechanical pump if there's lines going into and out of it. Get the big can corvette pump if you're worried about volume. And you definitely don't need to cut the arm off, just remove the pushrod from the block.
I don't get it. But if I was going to do it, I'd just run the electric fuel pump line to the carb and let it p*** under the mech. pump and let that be it. But, I still don't get it.
I've never done it personally but the flathead guys would often hook up an electric pump to flow right through a stock pump which is up on the intake manifold. They wanted the original look but the convenience of the electric pump. One word of caution is that if the original (old) pump diaphragm develops a leak from the modern gas (not too uncommon), the electric pump can and will pump the crankcase full of fuel with no outwardly signs of a problem obviously wiping out the engine with gas diluted oil. I'd be more inclined to just leave it and answer the the rare question from the very few about why the pump is not connected.
I was going to say what Tommy said in that it is a great place and way to create a gas leak into the oil pan. That said I have an electric pump pushing through a dead pump on my 71 GMC daily driver so I can't rag on you too hard. The old time flathead guys did it because if someone had put the pushrod in upside down it wore the cam lobe or end of the pushrod and the pump wouldn't keep up with demand at road speeds. They would stick an electric pump in line with the mechanical pump rather than swap out the cam and pushrod. I first heard of that in about 1957 or 8 when my stepfather had trouble with his 53 Merc's fuel pump. Still fake is fake and if they have their nose so far down in your engine compartment that they can see the blockoff plate they are getting personal. I'd rather see a blockoff plate and know you had an electric pump than hear that you thought you had to run a fake mechanical pump to make things look "right".
Oil pan fillin' guys, the man said he was going to cut off the arm AND use a block off plate to prevent that! Oh, and FAB32, while I have great respect for Garlits on the track and in the shop, he put his name and picture on a LOT of cheezy stuff back in the 60s and 70s. Of course, that was for the bucks and he has since built the drag museum, so we can all enjoy the fruits of that pimping.
I have a dummy fuel pump on my SBC. My block is a 1988 block and is not cast for a normal SBC mechanical fuel pump, there are no bolt holes, and there is no hole in the block for a fuel pump arm. I mounted the electric pump out of sight and I just didn’t like the look of a block off plate. I think the pump looks better. If I could have ran a stock pump I would have. Any way, I drilled and tapped the block to accept the fuel pump plate and pump. I took an aftermarket pump from a dollar bin at the swap meet and dis***embled it. I removed the foot, and milled the insides out until I could put a tube through the pump body. I used stainless compression fittings tigged to the tube so it looked like a stock style fitting and plumbed it as normal. The nice thing about the aftermarket pump was it can be clocked so that the lines are placed in the most convenient location. After it was done I blasted and painted it and no one has ever suspected other wise. Did I have to do this,…No!, but I like the look of the pump better than an empty cavity on the side of the block that was never meant to have anything bolted to it.
what he said. gut it and run a tube through it. don't want to risk kill'n the whole motor for looks. that would be the only safe way to do it as i see.
To the nay sayers and jokesters, I knew I'd catch some flack and no offense is taken but I'm doing this for me not you. Quite frankly I don't get what all the fuss about "fake" is about, it's not like I was running a fake blower or something, it's a friggin' stock fuel pump but I guess as long as you're raggin' on me you're leaving somebody else alone so have at it. Somebody "gets it", thanks!
If you would not have posted the above statement in your opening post I would not have posted my joke.... (I was only joking) When I read this line I ***umed you would either have a sense of humor or thick skin... after a few seconds of consideration I made the post........
It's not like the stock fuel pump is insuficient or robbing m***ive HP, so really if you want to go to the trouble of plumbing it, you might as well run it
If I was going to the trouble of plumbing the mechanical pump, I think I'd run it. The stock pump will put out more than enough gas to feed any street setup. I've run mechanical pumps on track only vehicles. You can get them that flow over 110 GPH and I never liked the idea of the car sitting on the roof with an electric pump pumping gas to feed what ever catastrophy is fixing to happen. Larry T
I ditched the mechanical pump on my Lincoln because of availabilty issues... I had read that an FE or Ford Y block pump would work but not so... Since I really wanted a mechanical pump, I pieced one together using a y-block pump and my old one, worked GREAT! for a day... Anyway I fabbed up a block off plate that incorporated a mount for a Carter electric pump. The electric pump is in the stock location and since it is low enough on the engine,on first blush it looks stock enough....
Stewart-Warner makes a nice safety shutoff switch that will work with battery powered ignition or magneto. Once oil pressure is lost, the fuel pump shuts off. I agree on the stock mechanical fuel pump being able to supply enough gas for any streetable carburetion setup. Ran one on three 2 bbls and six 2 bbls. No probs - 3/8" fuel line from the tank fwiw. Depending on who made your pump, you may be able to adapt the Carter racing mechanical pump to your body. Probably for GM cars only, but it's worth a look.
I used to carry a spare Holley red pump, but now carry a mechanical as a spare. It takes up room in the small toolbox so I plan to bolt it back on the engine and run the inlet line to the outlet fitting. That'll make it easier if the electric pump bites the dust.
If you're worried about avaliability I converted a Dodge 318 Mechanical pump to work on my S2D, it just took a little modification to the arm. I run 3 2bbl Rochesters with it on a 289ci
GMPP also makes a nice oil pressure switch. I think it allows 3 seconds without oil pressure before killing the pump. (delay allows the pump to work during cranking) Stock equipment on carbureted, electric pump cars like monzas and early 3rd gen F bodies. Once they went to EFI the logic was buried in the ECM instead of a seperate switch.
Use the stock pump and pump the fuel through it just like the factory did for years. very seldom did we have a problem with them. The electric will just pump thru the mechanical pump. Some guys actually just run the stock pump pulling thru the electric and use the electric when needed . Like a older buick with vapor lock etc.
I think you might be confused a bit...the oil pressure switch was a pump byp***...so if the FP relay quit (hence electric pump won't turn on) then cranking for 3 to 4 seconds would build up enough oil pressure to allow the switch to close and send power to the fuel pump...there was no "saftey" device on the 3rd gen f-body's or other GM's of the same era. But back to the original question, if I was going to do what was requested, I'd bore through the pump inlet and outlets and byp*** through it with a piece of tubing....I'd also cut the arm off 9***uming it ran on the cam...if it was like a SBC.BBC I'd just pull the pump rod..or if like a Ford/Mopar that i've had, I'd pull the eccentric lobe off so the arm would have nothing to ride on. Only reason I wouldn't just "push it through" is if the diapharm ruptued in the old pump you'd be filling the engine up with raw fuel.
Nope, early in-tank pumps on carbureted F and H bodies did not use relays. I've worked on a ton of both platforms fuel and electric systems. Actual pump power was routed thru the switch. To this day I have a 1979 H body with stock pump wiring, it runs for 3 seconds on initial key-on then shuts off if there's no oil pressure. If the car dies, it runs for 3 seconds after loss of pressure. I've had that car 22 years and am confident saying this. Pump relays did not appear until the FI era with higher demand pumps. I still have burn scars from trying to get those ******* wire plugs back onto the sender around hot hedders. What you describe is the system that early FI systems used with relays and an interlock switch. Later on they completely eliminated the switch and let the ecm handle it.
Going to an electric for 2 reasons. #1 Severe vapor lock. #2 Start up problems with the Performer carb after it sits for a couple days. The brand new stock pump can't maintain enough pressure to keep the fuel from vaporizing in warm weather and it takes a good 15 to 20 seconds of cranking to reprime the stock setup if it sits a couple days or more. A friend gave me a brand new Carter 4070 and since the #1 most popular resolution I have found for both my issues is an electric pump..... If the stock pump wouldn't be a restriction and overload the electric I'd just run it but I have my doubts. And I've experienced a couple ethanol related fuel system failures in the past couple years that could have very easily been catastrophic. I'm also just not warm and fuzzy about the diaghragm holding up to the pressure of the electric pump. Down the road I will replace the Performer but how far down the road I don't know. Lot's of other stuff to do to keep it on the road.
Did somebody already say. Leave the mechanical pump where it is and put the electric pump back by the gas tank like thousands (maybe millions) of us do it, already? The electric pump is mounted in series in the line, fuel goes through the mechanical pump like always.
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