Novak Conversions Jeep Wrangler TJ engine mounts

Fuel Pump Rebuild Questions

Jeepoftheseus

Jeepoftheseus

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Hey everybody,

My 98 TJ is a little slow to turn-over when the engine is cold, which is making me think it's time to rebuild the fuel pump assembly.

Everything I've read about replacement assemblies indicates they're not to be trusted, so I've decided to buy the parts to do it myself as suggested from another post (https://wranglertjforum.com/threads...p-without-replacing-the-whole-assembly.58080/)

I want to use the kit with the higher quality Denso pump, but it doesn't come with a replacement corrugated hose to atach to the pump itself. Does anyone have the measurements for the hose so that I can buy a new one?

I don't want to re-use the old one because I figure I should just do everything while I'm in there. Any advice about what else to do while I have the tank off is also appreciated.
 
Jeepoftheseus said:
Hey everybody,

My 98 TJ is a little slow to turn-over when the engine is cold, which is making me think it's time to rebuild the fuel pump assembly.

Everything I've read about replacement assemblies indicates they're not to be trusted, so I've decided to buy the parts to do it myself as suggested from another post (https://wranglertjforum.com/threads...p-without-replacing-the-whole-assembly.58080/)

I want to use the kit with the higher quality Denso pump, but it doesn't come with a replacement corrugated hose to atach to the pump itself. Does anyone have the measurements for the hose so that I can buy a new one?

I don't want to re-use the old one because I figure I should just do everything while I'm in there. Any advice about what else to do while I have the tank off is also appreciated.
Click to expand...

Hello, just what to follow up because I’m about to replace my fuel pump. You were able to replace it following the post?
 
I am still waiting for the Denso pump recommended in the instructional post to actually ship from the seller. I'm starting to suspect that the Amazon listing is a dead listing. It doesn't look like the other pumps available are of any quality either, so I've been considering just eating the cost on the pressure regulator and fuel lines and instead buying a Delphi assembly. I might even rig up a fuel pump access panel so that when the delphi dies every other week or whatever I can warranty it and put a new one in 🙃. From poking around the sub it seems like @macleanflood is the only guy who runs a Delphi and hasn't had any issues 😂 I've been considering making a new post and asking folks their thoughts about other pumps to try also.
 
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Jeepoftheseus said:
I am still waiting for the Denso pump recommended in the instructional post to actually ship from the seller. I'm starting to suspect that the Amazon listing is a dead listing. It doesn't look like the other pumps available are of any quality either, so I've been considering just eating the cost on the pressure regulator and fuel lines and instead buying a Delphi assembly. I might even rig up a fuel pump access panel so that when the delphi dies every other week or whatever I can warranty it and put a new one in 🙃. From poking around the sub it seems like @macleanflood is the only guy who runs a Delphi and hasn't had any issues 😂 I've been considering making a new post and asking folks their thoughts about other pumps to try also.
Click to expand...

Yeah, I can only see people recommend from other post is the Delphi one. The other store brands doesn’t look promising.
 
Jeepoftheseus said:
From poking around the sub it seems like @macleanflood is the only guy who runs a Delphi and hasn't had any issues 😂 I've been considering making a new post and asking folks their thoughts about other pumps to try also.
Click to expand...

Nope. I too saw too many Delphi pump failure posts.

I rebuilt my pump following the destructions posted in resources. The pump arrived made by Bosch Brazil. It lasted two weeks and died. That might have been my fault because, 1, I didn't clean out the tank completely and 2, didn't realize there was an additional filter sock on the bottom of the pump...my new Bosch Brazil pump assembly did not include one...nor did I find it later in the tank (if it had fallen off the original pump assembly.)

My third issue came later...my first pump assembly did not survive an accident...the plastic pump assembly frame cracked. The junkyard frame/tub I got had a pump assembly abandoned in the back seat. It ran and worked but only put out 30 psi. I replaced the pressure regulator on top, but still only got 30 psi.

I then purchased a Brute Power pump assembly off Rock Auto for about $80 shipped. Installed it. 50 psi. Zero issues for about the last year. Drove the Jeep down the freeway from Oregon, over the Rubicon Trail and home and plenty of miles and abuse since. It's twice "lost" the sender...fuel level dropped to zero...on hard impacts but comes back after a few minutes. I think that might be my fault for not clocking it correctly. The arrow points forward and not at the fuel line.

To ward off future demons I've done other mods. I added a Racetronix 5/16 QD to 1/8" adapter to the inlet of my rail and a permanently installed fuel pressure gauge. I'd like to replace that with a sender and an in cab gauge. I can tell at a glance if my cheap ass pump is dead. I carry a spare fuel pump...pump, not assembly...from the rebuild instructions the cheap Amazon sourced pump. It's in a plastic salsa jar with socks under my seat. I didn't want to use the Shrader valve on my fuel rail so I could verify the installed gauge accuracy with my known good OTC gauge.

Further...I've replaced my injectors with rebuilt, balanced OEM Siemens sourced from Precision Auto Injector. And added a DEI heat shield kit to the rail.

Recently I added a body lift and cut an inch off the skid, lifting the tank. I should have reclocked the pump assembly but forgot.

That Brute Power pump assembly has survived running out of gas on the freeway and sitting for two months with today's shit gas while I got deployed.

That's the entirety of my fuel pump saga.

-Mac
 
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macleanflood said:
Nope. I too saw too many Delphi pump failure posts.

I rebuilt my pump following the destructions posted in resources. The pump arrived made by Bosch Brazil. It lasted two weeks and died. That might have been my fault because, 1, I didn't clean out the tank completely and 2, didn't realize there was an additional filter sock on the bottom of the pump...my new Bosch Brazil pump assembly did not include one...nor did I find it later in the tank (if it had fallen off the original pump assembly.)

My third issue came later...my first pump assembly did not survive an accident...the plastic pump assembly frame cracked. The junkyard frame/tub I got had a pump assembly abandoned in the back seat. It ran and worked but only put out 30 psi. I replaced the pressure regulator on top, but still only got 30 psi.

I then purchased a Brute Power pump assembly off Rock Auto for about $80 shipped. Installed it. 50 psi. Zero issues for about the last year. Drove the Jeep down the freeway from Oregon, over the Rubicon Trail and home and plenty of miles and abuse since. It's twice "lost" the sender...fuel level dropped to zero...on hard impacts but comes back after a few minutes. I think that might be my fault for not clocking it correctly. The arrow points forward and not at the fuel line.

To ward off future demons I've done other mods. I added a Racetronix 5/16 QD to 1/8" adapter to the inlet of my rail and a permanently installed fuel pressure gauge. I'd like to replace that with a sender and an in cab gauge. I can tell at a glance if my cheap ass pump is dead. I carry a spare fuel pump...pump, not assembly...from the rebuild instructions the cheap Amazon sourced pump. It's in a plastic salsa jar with socks under my seat. I didn't want to use the Shrader valve on my fuel rail so I could verify the installed gauge accuracy with my known good OTC gauge.

Further...I've replaced my injectors with rebuilt, balanced OEM Siemens sourced from Precision Auto Injector. And added a DEI heat shield kit to the rail.

Recently I added a body lift and cut an inch off the skid, lifting the tank. I should have reclocked the pump assembly but forgot.

That Brute Power pump assembly has survived running out of gas on the freeway and sitting for two months with today's shit gas while I got deployed.

That's the entirety of my fuel pump saga.

-Mac
Click to expand...

Any recommendations on what pump to use? I know I will need one very soon. Jeep tj 2004 4.0
 
Rickyd said:
I've been running a bosch pump in the oem module for 30k miles and 5 years now. 4.6l stroker run hard.

I see no reason to run some cheap garbage
Click to expand...

Can you link the bosch pump? My big problem is that it seems like everything for sale is of dubious quality. I haven't been able to find a bosch.
 
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Jeepoftheseus said:
Can you link the bosch pump? My big problem is that it seems like everything for sale is of dubious quality. I haven't been able to find a bosch.
Click to expand...

Don't buy anything from amazon or ebay. Or any other site like them.rock auto included. It's possible bosch has dropped tj pumps. Idk. On my first tj they still made the whole pump module. If I wanted quality these days I would probably get a walbro or other good aftermarket
 
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