In-Tank Fuel Pump Adventure

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Renodemona
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In-Tank Fuel Pump Adventure

Post by Renodemona »

Greetings! I have been running FiTech for about a year now and had no issues with it, in fact was very happy. However a couple weeks ago the fuel pump died. It was an in-tank unit from Novak using a Delphi pump. After dropping the tank and taking he sending unit out I discovered that some wiring had its insulation rubbed off and apparently shorted out. Insulation repaired and pump seemed fine. I reinstalled and sure enough off we go again...or so I thought.

10 miles down the road pump dies again. So clearly either something in the wiring was more damaged than I thought or the shorting made the pump unhappy enough to fail. After reading through several forum threads and talking with Dr Marneus I've gone ahead and ordered the Tanks Inc PA-series in take pump. So, now I begin my quest to modify the tank to install the pump which will hopefully provide many years of fuel delivery. Stay tuned for pics of me messing up a fuel tank!
"Wait, what's on fire!?" KJ7TCT
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1976 Cherokee w/t 'Susan' 401/TH400/QT(PT)
FiTech Go EFI, Edelbrock Performer intake
3" Rough Country Springs, HEI Dizzy
-------------------------------------------------------------
2018 Cherokee Trailhawk V6 'Sedna'

will e
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Re: In-Tank Fuel Pump Adventure

Post by will e »

My 81 and 82 had an access panel to get to the sending unit and wiring without pulling the tank. Did the older jeeps not have the access panel? Can they be modified? I would hate to have to drop the tank any time I needed to replace a fuel pump.
81 Waggy 'WILL E' Retired
82 Cherokee WT - SOA/SF/high steer/Alcan springs/agr box/Borgeson steering shaft/AMC 401/performer/holley TA/HEI/BeCool/727/ALTAS (2.0/2.72/5.44)/D60 Snofighter(Yukon Zip,hubs,stubs,4.56)/14 Bolt (FF,BF shave, Discs, ARB,Artec Truss)/MTR 37X12.5/Corbeau XRS Baja & 5 point retractable harness/Hella Aux lights/tuffy console/killer32 sliders/Evil Twin bumpers, rack and roll cage/WARN 8000/TT Fabworks steering brace/dual batts/custom TC skid plate/ARB fridge
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Renodemona
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Re: In-Tank Fuel Pump Adventure

Post by Renodemona »

will e wrote:My 81 and 82 had an access panel to get to the sending unit and wiring without pulling the tank. Did the older jeeps not have the access panel? Can they be modified? I would hate to have to drop the tank any time I needed to replace a fuel pump.
They did not until 1980 I believe, something about the axles or transmission hump or something. Still working today will share pics when I finish up!
"Wait, what's on fire!?" KJ7TCT
--------------------------------------------------------------
1976 Cherokee w/t 'Susan' 401/TH400/QT(PT)
FiTech Go EFI, Edelbrock Performer intake
3" Rough Country Springs, HEI Dizzy
-------------------------------------------------------------
2018 Cherokee Trailhawk V6 'Sedna'
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babywag
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Re: In-Tank Fuel Pump Adventure

Post by babywag »

Renodemona wrote:Greetings! I have been running FiTech for about a year now and had no issues with it, in fact was very happy. However a couple weeks ago the fuel pump died. It was an in-tank unit from Novak using a Delphi pump. After dropping the tank and taking he sending unit out I discovered that some wiring had its insulation rubbed off and apparently shorted out. Insulation repaired and pump seemed fine. I reinstalled and sure enough off we go again...or so I thought.

10 miles down the road pump dies again. So clearly either something in the wiring was more damaged than I thought or the shorting made the pump unhappy enough to fail. After reading through several forum threads and talking with Dr Marneus I've gone ahead and ordered the Tanks Inc PA-series in take pump. So, now I begin my quest to modify the tank to install the pump which will hopefully provide many years of fuel delivery. Stay tuned for pics of me messing up a fuel tank!

Did you contact Novak to see about a replacement?
Pretty unusual for a pump to fail after that short a timeframe.
Got enough juice and proper wire/gauge/connections back there?
Repeated fuel starvation and heat will kill a pump in short order as well.
Fitech fuel pump pwm setting may be a factor as well? Some pumps aren't pwm compatible.
-Tony
'88 GW (aka Babywag)
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Stuka
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Re: In-Tank Fuel Pump Adventure

Post by Stuka »

Renodemona wrote:
will e wrote:My 81 and 82 had an access panel to get to the sending unit and wiring without pulling the tank. Did the older jeeps not have the access panel? Can they be modified? I would hate to have to drop the tank any time I needed to replace a fuel pump.
They did not until 1980 I believe, something about the axles or transmission hump or something. Still working today will share pics when I finish up!
The sending unit was in a different place, and I think it was one of those things they added down the road as a dealer request.
2017 JKU Rubicon
Pevious Jeeps: 1981 J10, 1975 Cherokee, 2008 JK, 2005 KJ, 1989 XJ
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Renodemona
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Re: In-Tank Fuel Pump Adventure

Post by Renodemona »

babywag wrote:
Renodemona wrote:Greetings! I have been running FiTech for about a year now and had no issues with it, in fact was very happy. However a couple weeks ago the fuel pump died. It was an in-tank unit from Novak using a Delphi pump. After dropping the tank and taking he sending unit out I discovered that some wiring had its insulation rubbed off and apparently shorted out. Insulation repaired and pump seemed fine. I reinstalled and sure enough off we go again...or so I thought.

10 miles down the road pump dies again. So clearly either something in the wiring was more damaged than I thought or the shorting made the pump unhappy enough to fail. After reading through several forum threads and talking with Dr Marneus I've gone ahead and ordered the Tanks Inc PA-series in take pump. So, now I begin my quest to modify the tank to install the pump which will hopefully provide many years of fuel delivery. Stay tuned for pics of me messing up a fuel tank!

Did you contact Novak to see about a replacement?
Pretty unusual for a pump to fail after that short a timeframe.
Got enough juice and proper wire/gauge/connections back there?
Repeated fuel starvation and heat will kill a pump in short order as well.
Fitech fuel pump pwm setting may be a factor as well? Some pumps aren't pwm compatible.
The wiring had the insulation stripped in a couple places either from installation or from banging around inside the tank. Either way I wanted a different solution. The "kit" is a stock fuel pickup with the sock replaced with an impeller style fuel pump from Delphi. They have discontinued that particular product, in fact the tech guy I called to find out why my order was taking so long said mine was the last one they put together. Its not a great design. I verified with Novak that it was PWM compatible. I don't think it was the pump itself that failed, but the signs of motion within the tank convinced me to go another direction.
"Wait, what's on fire!?" KJ7TCT
--------------------------------------------------------------
1976 Cherokee w/t 'Susan' 401/TH400/QT(PT)
FiTech Go EFI, Edelbrock Performer intake
3" Rough Country Springs, HEI Dizzy
-------------------------------------------------------------
2018 Cherokee Trailhawk V6 'Sedna'
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