In Tank CJ fuel pump?

HotJimmy

I've been fighting fueling problems with band aids for too long. This Jeep is a 1982 CJ7 street rig with a well built 401 and TH400. I initially had problems with vapor locking. I wrapped the fender well exits and it got better, but never good until I replaced the cheap napa electric pump with a nice Holley red label. Even still, on hot days it would occasionally vapor lock. I need to replace the stock fuel sending unit and while doing this I'm finally rerouting my fuel lines to a better location. But I want to put an in tank fuel pump while the tank is dropped as well. Has anyone ever seen or made a conversion for an in tank pump on a stock CJ tank? Carbed engine, so low pressure preferably. A high psi pump would work too with a return type psi regulator. Like I said, this is my street jeep not my crawler, so I want to retain the stock tank/ location and avoid a fuel cell.

tufcj

Where is your electric pump mounted? If it's under the hood, move it back as close to the tank as possible. That will solve most of your problems. Electric pumps are designed to push fuel, not draw. Fuel under pressure is less likely to vapor lock. I have a Trail Quest 22 gallon replacement tank in my CJ, with a 14-16psi GM internal pump for the Howell EFI. Sits in the stock location, but much beefier and holds 9 gallons more than the stock tank. I would think that a shop could weld in the right lock ring for a GM style pump in the stock tank. You would then have to regulate it for the 5-6 psi needed for a carb. Bob tufcj

HotJimmy

Pump is about 2'-3' from the tank. I'm going to try and modify a new sending unit to attach an in tank pump. I just need find the right application

tufcj

GM fuel pumps from early TBI cars/trucks (late 80s, early 90s) should be pretty simple. The pump is about as big as a pill bottle, and stands upright, drawing from the bottom. The line is either 5/16 or 3/8, I can't remember. You may be able to modify the current sender to fit the pump, and add a bulkhead connector for the wires to pass thru. The pumps do need return fuel to cool them. Factory tanks have a box around the pumps to keep them submerged, and the return fuel line pumps into that box. Probably wouldn't be too difficult to reproduce, and could probably be epoxied into the bottom of the tank. Last thing would be a regulator, since most in tank pumps were for EFI cars, you'd need to limit pressure to 5-7 PSI. Bob tufcj

JeepBuilderinTN

HotJimmy;124005 wrote
I've been fighting fueling problems with band aids for too long. This Jeep is a 1982 CJ7 street rig with a well built 401 and TH400.

I initially had problems with vapor locking. I wrapped the fender well exits and it got better, but never good until I replaced the cheap napa electric pump with a nice Holley red label. Even still, on hot days it would occasionally vapor lock.

I need to replace the stock fuel sending unit and while doing this I'm finally rerouting my fuel lines to a better location. But I want to put an in tank fuel pump while the tank is dropped as well.

Has anyone ever seen or made a conversion for an in tank pump on a stock CJ tank? Carbed engine, so low pressure preferably. A high psi pump would work too with a return type psi regulator.

Like I said, this is my street jeep not my crawler, so I want to retain the stock tank/ location and avoid a fuel cell.

I just did one in my 82 CJ7 Limited I put a 4.0 and in tank pump.

I used the stock sending unit, some fuel injection rated hose and a pump from an 87-91 YJ Wrangler w/4 cylinder TBI (this pump should work fine for your application as well.