I have an 82 Corvette with a carb conversion. I am wondering if I can take the electric fuel pump out of the tank and replace it with a regular unit?

Let me start over. I put a manual fuel pump on the engine. It's pulling its fuel through the electric fuel pump that's in the tank and now the fuel is dripping into the carburetor when I shut the engine off. It won't start back without pushing the accelerator to the floor. What do I need to do to remove the electric fuel pump?

 

I think you can just use a regulator with a return line which you should have already

 

'82 corvettes have an electric fuel pump? Then why don't the people wanting to convert from mechanical use that setup?

 

They do ..

 

Alright; let me rephrase my question

Why does it seem people prefer to install newer units, when an all worked out conversion is pretty much lying on the table? Or does the '82 electronic fuel pump and plumbing have certain disadvantages?

 

Original post:
You can remove the sending unit and install it WITHOUT an electric fuel pump....but you would then have to install a mechanical fuel pump on the engine block itself.

Can not understand what you wrote on the last post.

If you have a carburetor converted engine on an 1982...and you are still using the electric fuel pump...a pressure regulator has to be installed to control/regulate the fuel pressure to 7-9 psi...and also there has to be a way of making a fuel return so fuel can return back to the fuel tank. I have recently made this fitting to make a fuel return so vapor lock issues would be taken out if the scenario. I wanted the regulator at the back of the car so the fuel return was up at the engine so the fuel in the supply line was just not sitting there getting hot...and it would get circulation at the area of where the mechanical fuel pump would be located...just like a earlier year Corvette.

People with 1982 that install "newer units" is where you lost me. Are you talking about fuel pumps that have more pressure or what. I just do not get what you mean by "newer units"???

DUB

 

82's have cross fire injection and a 15 psi intake fuel pump. With a carb conversion it is easier to just use a fpr to lower the fuel pressure to 5-6 psi and use the oem return line as stated above. You can remove the intank pump and install a low pressure intank pump or install an external inline pump near the gas tank if there is room. A Carter 4070 electric pump is a good street pump to use. I have a carbed 84 C4 and use a Mallory 4309 fuel pressure regulator which is for use with a return line. I also have a delco low pressure external style fuel pump that I carry in my tool box that I can hook up to my carb fuel line should my intank pump go out. Contrary to what some say it will pull through a dead pump enough to get you home safely. I read about 3 psi pulling through the rear pump with no power to it. It takes me about 5 minutes to connect the backup to the carb and I have alligator clips to connect direct to the battery(on a c3 you could connect to the power post on the back of the alternator.).

 

Not specifically '82, but C3's more in general. Lots of questions about how to route, which regulator to use and how to wire. The Holley blue and red type seem popular.

But: why not simply copy the '82 stock setup? If I were to install an electric fuel pump on my '79, this would seem the easiest route. So...
Insufficient pressure for modern EFI? Unsafe? Parts no longer available? Or simply a matter of people not knowning?

 

It depends on what you are working with and what you want to accomplish. The 82 unit not would not work for me, (LS injected swap, 74 tank).
The pump would need to be replaced with a higher flow & pressure unit, then the wiring would be too small. 74 tank is a different shape and it would not just bolt in. If I did put it in my tank it would have no reservoir/sump to limit fuel pump starvation that is a real problem with injection. Its just like picking a cam for an engine - you have to balance the system for best results. Could it work for a carb if you added a regulator? Yes - if it flowed enough for the engines needs.

 

Angus, what is the reason you want to go with a mechanical pump? Are you using the 82 fuel pump and wiring ? Are you using a fuel pressure regulator? What problems are you having?

 

I AM SORRY "worship79"

I got twisted up in this post and for some odd reason I thought you were the original poster and then followed up with your question is where my confusion came into play. I feel like and idiot.

To answer this quoted post from you. If I were to have to install and electric fuel pump in a Corvette that was originally a mechanical pump....and it was a 1978-1981. I would buy the 1982 sending unit and pump....and then plumb in a fuel pressure regulator ( at the rear of the car with bumper cover removed)....and then make the special "T" fitting I have made before that allows the fuel to return back to the tank from up at the engine just like a mechanical pump does originally.

If I had to install a pump in the 1978-1982 tank using the same 1982 sending unit...but using a pump that was much higher pressure due to engine requirements. Then I would have to consider the type of rubber hose being better quality than standard fuel hose ( which is usually rated to 50psi)...I would use a newer type bio-fuel hose that can handle much higher pressure ( 200+psi) for safety reasons. Then I would have to make sure my clamping is sufficient...which usually mean using two clamps on the pressure side (like 1985-1996 Corvettes have)...OR...I would cut the fuel supply line and either flare it to 37 degrees or install the AN fitting for a hard line. Then weld on a male end to the fuel supply tube on the sending unit so the fuel supply hose that goes from the sending unit to the supply line at the fuel tank does not use hose clamps. It all depends on eh fuel pressure and knowing that accessing the fuel lines at the tank are hard to get to with the bumper cover on.

I prefer to have the fuel pump in the tank. But that is just me.

DUB

 

The 82 Pump is not known as one of the better pumps out there. Somebody figured out that a early C4 Pump was better and a bunch of them got installed. This was before aftermarket pumps were as easy to get as they are now. The 82 Pump-Sending unit is all made from Pot Metal and nothing can be welded to adapt another Pump. But if the replacement is close in size and fit to the original they have been adapted many times. All of this probably doesn't much matter to a car that has lost its FI system.

 

That is correct Gale Banks 80. The guys that replace there 82 and 84 crossfire pumps with the 1985 50 psi fuel pumps still have their tbi injection system. There were some gm cars that were carbed and had intank 6 psi fuel pumps from the factory but I am not sure which models had them. I have the Carter 4070 inline pumps on my 455 dual quad Gto and my 78 Ford Ranchero 460 and they work great.

 

Thanks guys!

 

This is odd. I have serviced numerous 1982 sending units and pumps and I have never had one that was made out of pot-metal. They are all steel construction that has been plated. And most of what I have serviced were badly rusted....and as we know...pot metal does not rust.

As for a pump. I have searched "long and wide" and I can not find a fuel pump that from GM was 6 psi. And those that were lower in pressure really were not and when I check the head pressure...it was higher than I liked...usually in the 11+psi range. And these pumps were designed to replace the original unit without any modifications...basically a direct "bolt-on" ...so-to-speak.

DUB

 

The airtex e2485 intank fuel pump is a replacement pump for many carbed 70's and early 80's gm, ford, bmw and other makes. Some models used both an intank and mechanical pump. This pump is rated at 4-6 psi and 20-30 gph. If you go to amazon.com and input the airtex part number you can select a listing of vehicles it fits. As Dub says some may put out more psi than rated at. Whether this pump will easily adapt to an 82 or 84 pump assembly is anyone 's guess.

 

I have installed a manual fuel pump on the engine. It's pulling its fuel through the electric fuel pump that's in the tank and now the fuel is dripping into the carburetor when I shut the engine off. It won't start back without pushing the accelerator to the floor. I want to remove the electric fuel pump.

 

Sounds like you may be having fuel percolating problems. Carb is getting hot from too much engine heat. Are you using a carb insulator between the carb and intake manifold?? I would let your engine idle for awhile and keep your hood open. Then shut the engine off for awhile and then try to restart. Check to see if carb is still dripping gas. You should check your carb float level and carb inlet needle and seat for proper operation too.

 

Floats sound like they are adjusted to high. What kind of a carb is on the motor

 

Sure, remove the pump and replace with line/tubing to complete the pickup. Just use "in fuel" compatible materials.
The fuel dripping into the engine is not from the electric pump. It could be a number of things:
1 trash/material in the needle & seat - need good filter
2 worn needle & seat
3 fuel pressure too high
4 float setting too high
5 percolation - fuel boiling -