LS Fuel Pressure Issue High Hot (1 Viewer)

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All of those lines should be hooked up. They just get hooked up in the same order on the tank, pretty straight forward. That bottom-most hose goes to the charcoal canister. Someone welded a drain plug directly into the fuel pump well for some reason, probably what some of those burnt chunks are. Just weld residue.

On to the fuel pump bracket: That bolted connection for the positive wire is pretty suspect, as is the bolted ground connection. Second, the big thing is they have cut and modified the fuel pump bracket (crazy, since they're NLA and go for $400+ used). It looks like they welded the bottom of another fuel pump bracket onto the existing one.

With the factory fuel pump, the filter actually sits ABOVE the bottom of the bracket, and it would be impossible for the filter to be crushed into the pump inlet. Here's a picture:
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I suspect yours is the type of pump that has the filter that plugs right into the bottom of the pump through the bracket (so it hangs down below the bracket). That, coupled with the bracket likely being a little longer is probably cramming the fuel pump sock hard up against the bottom of the tank. Not sure how you'd fix that besides switching back to an OEM style pump or shortening the bracket.
Should I retrofit the pump house lid pass through fittings and install the 90s like you have with barbed connections, or leave it alone?

What pump is that with the pickup and sock to the side? That’d get the sock out of the mucky muck that settles on the drain?

the rusted rivets and the slag anything I can clean out is easy, on the rivets should I knocked the rust off or leave it alone.

Last question I promise, I didn’t find the gaskets for the sender and pump, is that an easy on to find to cross reference or just cut some?
 
That is not a picture of my sending unit. That person just did that to fix damaged/rusty lines and sending units. If your pipes are fine, leave them be.

That is an OEM Denso pump. May or may not provide enough fuel for a V8 application. Doesn't really matter though, since your pump bracket has been modified and will not longer accept an OEM pump.

Clean as much as you can

Both rubber gaskets are still available from Toyota dealers. I ordered some from my local toyota dealer a few months ago.
 
Dont get any kind of fancy aftermarket pump, get yourself a fresh genuine Denso pump (OEM Toyota), i use the ones from the 4th Gen 4Runner, they are compact and fit easily. This will last the life of the vehicle and i have used on plenty of conversions.
 
About as clean as it’s going to get. Tank was washed several times until the junk stopped flowing. Going back in tomorrow to blast it out with carb cleaner. The bracket was shortened 3/8 to get off the bottom. Clean connections tomorrow and install stainless access door in floor cause homie not doing that again. I have the e85 worthy hoses coming tomorrow so hopefully no meltdowns of rubber again.

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I have had the same issues with a RamJet.....and then the same with my LS3..
 
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I have had the same issues with a RamJet.....and then the same with my LS3.....this will be the most important question with your post...Is this an inline pump or intank pump?
In tank. But found sub standard vent lines and melted rubber floating around that got sucked into sock. But many other issues corrected
 
Good call on replacing everything 👍🏼
When I was trying to piece new lines and fittings to old stuff, today I just stopped and gutted everything. Scary moment but think it’ll be worth knowing the weak link won’t be in the rear, at least for a bit. Now need to rip a hole in the bed and install that Tanks Inc door. Take to welders next week and seal it
 
I have had the same issues with a RamJet.....and then the same with my LS3.....this will be the most important question with your post...Is this an inline pump or intank pump?
They did in tank 2 years ago at Top Line in LA and did a s?!t job
 
I had some fueling issues with my in tank pump I had to work out at first. I had hoses and mounting come loose.. also a bad filter/regulator. Fortunately I made a hatch in The cargo area so it hasn’t been as bad as it could be. But I hate dealing with gasoline nonetheless it sucks.

I’ve been running the following setup for over 70k miles and it has been very reliable.

Returnless style rail, Walbro in tank, used a rubber isolator on the pump (dense rubber sleeve) dampen vibration and noise.. and made sure it was very well secured to the hanger. I also used stainless safety wire on the hose end connections to make double sure the hoses weren’t gonna come off. Gates submersible 3/8 hose. 3/8 Teflon steel braided A/N supply/return to corvette filter/regulator. 3/8 hardline to upper firewall then 3/8 braided to rail. 10ga wire from relay to pump for the juice.

It looks like what you’re putting together is fantastic

I would be sure replace the filter while you’re at it.. may have sucked some of that crud up
 
I had some fueling issues with my in tank pump I had to work out at first. I had hoses and mounting come loose.. also a bad filter/regulator. Fortunately I made a hatch in The cargo area so it hasn’t been as bad as it could be. But I hate dealing with gasoline nonetheless it sucks.

I’ve been running the following setup for over 70k miles and it has been very reliable.

Returnless style rail, Walbro in tank, used a rubber isolator on the pump (dense rubber sleeve) dampen vibration and noise.. and made sure it was very well secured to the hanger. I also used stainless safety wire on the hose end connections to make double sure the hoses weren’t gonna come off. Gates submersible 3/8 hose. 3/8 Teflon steel braided A/N supply/return to corvette filter/regulator. 3/8 hardline to upper firewall then 3/8 braided to rail. 10ga wire from relay to pump for the juice.

It looks like what you’re putting together is fantastic

I would be sure replace the filter while you’re at it.. may have sucked some of that crud up
Other than the hard line mid ship exact same setup. Vette regulator, all AN stuff, SAE J30R7 (lower psi) on vent lines not carrying fuel and J30R9 on everything else.

My pump has a rubber seat it centers pump at bottom. Cross my fingers but damn this has been a methodical process I didn’t bargain for. One that I’ve seen on the 60s and the access door is haven’t seen a setup that looks well bad ass and water tight. The corrugated with a flat door just seems like there’s something better than weather seal put on thick or using the original cut piece jagged piece, pieced back in. Got the be someone who’s come up with a good transition? Maybe it’s you??
 
One that I’ve seen on the 60s and the access door is haven’t seen a setup that looks well bad ass and water tight. The corrugated with a flat door just seems like there’s something better than weather seal put on thick or using the original cut piece jagged piece, pieced back in. Got the be someone who’s come up with a good transition? Maybe it’s you??
This is the best one i have seen @Bullzi

 
This is the best one i have seen @Bullzi

Welp can’t unsee that
 
re-do your in tank, and I'd bet to say this will resolve your issue. I see you started with a inline frame mount. I was atthe end of my line to figure out my fueling issue......Spoke with a high end Cruiser builder buddy here in Colorado, he advised go with in tank Aeromotive..we shall see, i will report back here in two weeks.
 
This is the best one i have seen @Bullzi

@cruisermatt

I was just looking at his access, it’s nice and work towards that.
 
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re-do your in tank, and I'd bet to say this will resolve your issue. I see you started with a inline frame mount. I was atthe end of my line to figure out my fueling issue......Spoke with a high end Cruiser builder buddy here in Colorado, he advised go with in tank Aeromotive..we shall see, i will report back here in two weeks.
It’s been in tank pump for 2ish years, but yeah I think all this cleanup will help, I damn sure hope! This is how I discovered I had issues with tank, also as a test I ran a beer tap brush up all the vent lines and particles of rubber everywhere. Idk how bad is bad but look at that intake and fuel I strained through towel from last gallon of fuel. Good luck buddy, this about broke my spirit, trying to figure out.

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