Fuel Cells and Fuel Systems

AssBurns

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Figured I'd start a discussion thread on fuel cells and fuel systems since this is something I am sorta new to and wanted to get some feedback from others on their experiences.

Share some knowledge and feedback if you have any experience with this stuff.
 

AssBurns

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First up, I'll start with my current situation and limited experience.

I recently ordered a JAZ 32 Gal Jeepspeed fuel cell, but plans changed and I have to go a different route due to packaging constraints. Well JAZ has a crazy backorder on most of their fuel cells, and the one I am looking to buy (another 32 gallon fuel cell in different dimensions) is back ordered until December according to Kartek. So now I am considering different options due to the timelines. I've heard decent stuff about JAZ but I've always heard good things about Fuel Safe. They are a bit more expensive so I just always kept my budget around JAZ products for myself until now. I messaged Fuel Safe this afternoon to get a better idea what sort of timeframe I could expect from them for a 32 gal fuel cell. Hoping it's not 6+ months.

Now that being said, I will have to start considering different plumbing options for my fuel system. From my knowledge an in-tank fuel pump is more reliable due to cooling and always being saturated in the fuel itself. Just a bit more work to swap pumps in the event of a failure.
For the sake of discussion, what in-tank pump setup do you guys have experience with and recommend? I will be going with a Holley Hydromat for the pickup since everyone I talk to says that is the way to go.
 

Stairgod

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Harmon Fuel Systems does one off cells. Might be worth giving them a call.
I am of two minds with in tank and external pumps. Replaced more than my fair share of both over the years.
I always liked the idea of a bottom sump and external pump to alleviate fuel starvation issues at extreme angles but I doubt that is a concern for you.
Depending on your fuel flow needs I would stick with an OE pump from almost any manufacturer.
If the rig isn't getting an engine swap and the stock pump worked well then run that.
 

AssBurns

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Harmon Fuel Systems does one off cells. Might be worth giving them a call.
I am of two minds with in tank and external pumps. Replaced more than my fair share of both over the years.
I always liked the idea of a bottom sump and external pump to alleviate fuel starvation issues at extreme angles but I doubt that is a concern for you.
Depending on your fuel flow needs I would stick with an OE pump from almost any manufacturer.
If the rig isn't getting an engine swap and the stock pump worked well then run that.
I forgot about Harmon. I know they make quality stuff but definitely not cheap from what I've heard. I'll check them out!

What is it about external pump that makes starvation different from an in tank pump? Isn't it more about the pickup than the pump at that point?

The rig has a mostly stock 5.3 LM7 so I'd guess a stock GM pump might work for fuel flow needs. Maybe get one from a 6.0 or 6.2 model truck so it already can keep up with more flow in an OEM format. Probably a lot cheaper than something like Aeromotive.
 
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The Holley Hydromat is pretty sweet, I wonder if some type of similar system could be developed for the oil pan pick up for the same reasons.

I am currently researching and trying to figure out my fuel tanks and fuel pump/s. Currently planning to make them with aluminium.
 
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Stairgod

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I forgot about Harmon. I know they make quality stuff but definitely not cheap from what I've heard. I'll check them out!

What is it about external pump that makes starvation different from an in tank pump? Isn't it more about the pickup than the pump at that point?

The rig has a mostly stock 5.3 LM7 so I'd guess a stock GM pump might work for fuel flow needs. Maybe get one from a 6.0 or 6.2 model truck so it already can keep up with more flow in an OEM format. Probably a lot cheaper than something like Aeromotive.
It's not the pump that makes a difference in fuel starvation so much as the sump.
Obviously depending on the severity of the angle the sump needs to be designed for the conditions.
I always wanted to tinker with a dual pickup set up with check valves but ended up selling the rig.
 

AssBurns

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It's not the pump that makes a difference in fuel starvation so much as the sump.
Obviously depending on the severity of the angle the sump needs to be designed for the conditions.
I always wanted to tinker with a dual pickup set up with check valves but ended up selling the rig.
Maybe I'll call the guys at Fuel Safe and Harmon to pick their brain on pickups and sump boxes. I plan to do some mild crawling in this but mostly focused on desert stuff.
 

Stairgod

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Maybe I'll call the guys at Fuel Safe and Harmon to pick their brain on pickups and sump boxes. I plan to do some mild crawling in this but mostly focused on desert stuff.
Never had any issues in my Taco with fuel starvation, but then again I dont push it like I did my caged CJ-5. Once it had EFI I only had issues on the steepest shit.
 
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I'm I just not understanding what the Holley Hydromat does, the way I was reading the manufacture site, it seemed to b a bag/filter that acts as a "sump" and gives the ability to pull fuel from anywhere on the tanks bottom and because of the mesh sizing holds the fuel where the pump can get said even in low fuel, hard stops, cornering , angles.... while still allowing fuel to get through?
 

Stairgod

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I'm I just not understanding what the Holley Hydromat does, the way I was reading the manufacture site, it seemed to b a bag/filter that acts as a "sump" and gives the ability to pull fuel from anywhere on the tanks bottom and because of the mesh sizing holds the fuel where the pump can get said even in low fuel, hard stops, cornering , angles.... while still allowing fuel to get through?
Yes. Think of it as a baffle/reservoir. It uses capillary action to draw fuel from areas where it is touching the fuel but not draw air from areas of it that exposed to air.
Holley does not say exactly but I am sure that there is a cut off somewhere when too much surface area is exposed to air that it will actually draw air into the mat.
I don't know anyone who personally uses it but it sounds promising for short term fuel starvation issues.
 
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