In-tank Fuel Pump Modification

[jacobthegoat]

After completing this modification, I started to overthink my doings and pose this simple question:

The small connection between the pump and the lift assembly I used a small section of BMW fuel hose with a reducer as shown by cek.

Is the standard fuel hose used for this modification rated for in tank use? Is the fuel line “submersible” or will it deteriorate over time? It doesn’t specifically say submersible but cek seems to be using the same hose as I did.


I used the TRE 340 and stock BMW fuel lines
Part # here - 13-53-7-563-456

[glowell222]

I can't answer your question. I can state that I used typical BMW fuel line for that small section. After about a month, I was having problems making it up steep hills-almost like a fuel starvation issue. I pulled the assembly from the tank, thinking something had come loose. I found that small section had deteriorated and was loose. I replaced it with fuel line specifically rated for submersion. So far, no trouble, and we will have to see if it bears this out.

[Shawn D.]

It's expensive, but I have been sourcing and using specific "submersible" hose for in-tank use. Given the trouble and labor involved, it's worthwhile, IMO.

[davintosh]

I'd be hesitant to use standard fuel hose in the tank.

I didn't really think about that much beforehand, but on both of the cars I've done, the pumps came with a kit that included a section of fuel hose. Looking back at it the site I bought the most recent one from, it doesn't specifically say it's submersible, but since the vendor specializes in fuel pumps I think it's safe to assume it'll work.

https://www.highflowfuel.com/genuine-wa ... -gss340g3/

[funkycharms]

Thanks for bringing this up. I just completed the upgrade 2 weeks ago, and didn't even consider. Ended up stuffing some of the provided tre hose into a standard 13mm line. Guess it's something I'll keep an eye out for

[harrypalmer]

It would be most helpful if glowell222 could actually name the brand and or reference of said submersible hose for anyone's interest.

BTW and FWIW, had previously commented having some sort of hiccups with my own pump mod, but I was wrong as it is only susceptible when the fuel gets too warm (very particular to my car). Will be installing a fuel cooler next week and report.

[Shawn D.]

It would be most helpful if glowell222 could actually name the brand and or reference of said submersible hose for anyone's interest.

It's not hard to find, just search the interwebs for "submersible fuel hose." I recently got some from Summit Racing.

[glowell222]

It would be most helpful if glowell222 could actually name the brand and or reference of said submersible hose for anyone's interest.

It's not hard to find, just search the interwebs for "submersible fuel hose." I recently got some from Summit Racing.

This is exactly what I did (Summit Racing), and I had to buy several different diameters to work out which one was best. Of course, I don't recall which one I ended up using, so double-useless on my part-apologies for that.

[harrypalmer]

BTW and FWIW, had previously commented having some sort of hiccups with my own pump mod, but I was wrong as it is only susceptible when the fuel gets too warm (very particular to my car). Will be installing a fuel cooler next week and report.

A year later, have installed a E28 specific fuel cooler. It does greatly improve the engine's drive ability in traffic. However, the fuel starvation is present when pulling hard (4,500 to 6,500 rpm via a D'sylva chip) which is the way I mostly drive. Anyway, I am going to take the intank fuel pump out and get a dedicated submersible fuel hose like Davintosh suggested earlier. And report back again.

Does anyone out there, have experienced fuel starvation with this fuel mod?

[1st 5er]

BTW and FWIW, had previously commented having some sort of hiccups with my own pump mod, but I was wrong as it is only susceptible when the fuel gets too warm (very particular to my car). Will be installing a fuel cooler next week and report.

A year later, have installed a E28 specific fuel cooler. It does greatly improve the engine's drive ability in traffic. However, the fuel starvation is present when pulling hard (4,500 to 6,500 rpm via a D'sylva chip) which is the way I mostly drive. Anyway, I am going to take the intank fuel pump out and get a dedicated submersible fuel hose like Davintosh suggested earlier. And report back again.

Does anyone out there, have experienced fuel starvation with this fuel mod?

My only delivery issue has been when tank is extremely low on fuel, ~ 1/8 tank, and under hard cornering.
Submersible high pressure hose is a must.
Somebody out there knows the rating numbers,
or they may be listed earlier in this thread.

[gwb72tii]

Ask Charlie what he did with Vlad

[harrypalmer]

My only delivery issue has been when tank is extremely low on fuel, ~ 1/8 tank, and under hard cornering.
Submersible high pressure hose is a must.
Somebody out there knows the rating numbers,
or they may be listed earlier in this thread.

When you say 1/8 tank, how much fuel would you say is that in gallons?
In my case I feel fuel starvation occurs when there are roughly 4 gallons left in the tank (if I don't accelerate hard I won't notice it at all) but as mentioned earlier I usually drive hard, which makes the fuel range obsolete, or about 150 miles.

BTW my fuel pressure last time I measured (two different fuel regulators) read fine. Should I try larger fuel injectors at this point?
Any suggestions welcomed.

[harrypalmer]

Ask Charlie what he did with Vlad

I will. Thank you.

[tig]

Ask Charlie what he did with Vlad

I will. Thank you.

Like I remember. I'm regularly doing mye28.com searches on topics, finding threads with great writeups on how to do things, and then discovering that I'm reading something *I* wrote. ADHD FTW!

[1st 5er]

My only delivery issue has been when tank is extremely low on fuel, ~ 1/8 tank, and under hard cornering.
Submersible high pressure hose is a must.
Somebody out there knows the rating numbers,
or they may be listed earlier in this thread.

When you say 1/8 tank, how much fuel would you say is that in gallons?
In my case I feel fuel starvation occurs when there are roughly 4 gallons left in the tank (if I don't accelerate hard I won't notice it at all) but as mentioned earlier I usually drive hard, which makes the fuel range obsolete, or about 150 miles.

BTW my fuel pressure last time I measured (two different fuel regulators) read fine. Should I try larger fuel injectors at this point?
Any suggestions welcomed.

~ 2 gallons.
Typically would be just about the time the light would come one. It had only happened on a hand full of occasions, as I don't normally let the tank get that low. It's usually refilled around 1/4 tank or better.

I have no fuel pressure or injector recommendations.

[harrypalmer]

Ask Charlie what he did with Vlad

I will. Thank you.

Like I remember. I'm regularly doing mye28.com searches on topics, finding threads with great writeups on how to do things, and then discovering that I'm reading something *I* wrote. ADHD FTW!

LOL. Spot on!

[harrypalmer]

My only delivery issue has been when tank is extremely low on fuel, ~ 1/8 tank, and under hard cornering.
Submersible high pressure hose is a must.
Somebody out there knows the rating numbers,
or they may be listed earlier in this thread.

When you say 1/8 tank, how much fuel would you say is that in gallons?
In my case I feel fuel starvation occurs when there are roughly 4 gallons left in the tank (if I don't accelerate hard I won't notice it at all) but as mentioned earlier I usually drive hard, which makes the fuel range obsolete, or about 150 miles.

BTW my fuel pressure last time I measured (two different fuel regulators) read fine. Should I try larger fuel injectors at this point?
Any suggestions welcomed.

~ 2 gallons.
Typically would be just about the time the light would come one. It had only happened on a hand full of occasions, as I don't normally let the tank get that low. It's usually refilled around 1/4 tank or better.

I have no fuel pressure or injector recommendations.

5er, Thank you for your answers. I'll keep re-reading this whole thread and make adjustments. Maybe my Tre 255 is defective? Willing to replace it or get the Walbro. I'll keep you all informed.

[1st 5er]

My only delivery issue has been when tank is extremely low on fuel, ~ 1/8 tank, and under hard cornering.
Submersible high pressure hose is a must.
Somebody out there knows the rating numbers,
or they may be listed earlier in this thread.

When you say 1/8 tank, how much fuel would you say is that in gallons?
In my case I feel fuel starvation occurs when there are roughly 4 gallons left in the tank (if I don't accelerate hard I won't notice it at all) but as mentioned earlier I usually drive hard, which makes the fuel range obsolete, or about 150 miles.

BTW my fuel pressure last time I measured (two different fuel regulators) read fine. Should I try larger fuel injectors at this point?
Any suggestions welcomed.

~ 2 gallons.
Typically would be just about the time the light would come one. It had only happened on a hand full of occasions, as I don't normally let the tank get that low. It's usually refilled around 1/4 tank or better.

I have no fuel pressure or injector recommendations.

5er, Thank you for your answers. I'll keep re-reading this whole thread and make adjustments. Maybe my Tre 255 is defective? Willing to replace it or get the Walbro. I'll keep you all informed.

Been running Tre since the beginning of this thread w/o one failure.

[harrypalmer]

Been running Tre since the beginning of this thread w/o one failure.

1st 5er, I think you are right. The TRE should not to be blamed. I'm thinking perhaps one of the fuel lines is being squeezed or jammed a bit between the tank and the car's body? In any case, going to disassemble and report back. Thank you!

[BDKawey]

Spoke with someone from tre performce. they confirmed I am safe to simply install the tre in the tank and leave the in line pump in place and will be perfectly safe.

currently experiencing 1/4 hesitation and I want to retain the safety of having the in line pump with another pump supporting it. I have a barb reducer on the way as well to throw in the glove box if theres ever a problem with the in line pump. doing this because a) lazy. b) reliability of 2 pumps.

just wanted to pass along that information. flame me if you'd like since its not what most people have been doing.

[1st 5er]

I wasn't aware the inline pump would allow that much free flow.

But, hey, it if works...

Looking toward to hearing your actual results.
I carry a spare hanger with Tre pump attached, extra hose, etc., in any car I drive that hasn't been swapped. If your work around works it'll save crawling under the car on the side of the highway when it's 110° outside.

[Ju@n]

Spoke with someone from tre performce. they confirmed I am safe to simply install the tre in the tank and leave the in line pump in place and will be perfectly safe.

currently experiencing 1/4 hesitation and I want to retain the safety of having the in line pump with another pump supporting it. I have a barb reducer on the way as well to throw in the glove box if theres ever a problem with the in line pump. doing this because a) lazy. b) reliability of 2 pumps.

just wanted to pass along that information. flame me if you'd like since its not what most people have been doing.

I haven't removed it, but it was working last time I checked, so not sure it's the same scenario as yours

[BDKawey]

Spoke with someone from tre performce. they confirmed I am safe to simply install the tre in the tank and leave the in line pump in place and will be perfectly safe.

currently experiencing 1/4 hesitation and I want to retain the safety of having the in line pump with another pump supporting it. I have a barb reducer on the way as well to throw in the glove box if theres ever a problem with the in line pump. doing this because a) lazy. b) reliability of 2 pumps.

just wanted to pass along that information. flame me if you'd like since its not what most people have been doing.

I haven't removed it, but it was working last time I checked, so not sure it's the same scenario as yours

mine is functioning. if it werent i would certainly remove it because it very well may restrict flow if it did crap out. suppose thats the only argument to removing it.

years ago on this thread I asked about leaving it in place and was advised to remove it because the tre/walbro may not like to pump through it. so just wanted to circle back and say its perfectly safe per the manufacturer

[Ju@n]

Ah! then we are on the same boat

[BDKawey]

Dang I ordered it monday at lunch and it came today, costa mesa to columbus in 2.5 days. The first and only email i got said that it was pending review from sales staff.