Hey guys, the Bosch 255 lph fuel pump i got from mike seems to be making alot of noise. Is this normal. I can hear it in the cab or outside the truck plain as day. I am also seeing 28Psi at idle, 30psi cruising, and 42 WOT, Does this sound right??

 

Why didn't you just ask me directly?

Call me on Monday and I will take care of you, I stand behind the parts that I sell.

BTW, your fuel pressure sounds OK.

 

I didn't mean anything by it Mike. I was just curious and didn't have anything to compare to. Being as it was the weekend i thought i'd post it then call you monday.

 

I have a 255 lph in tank pump. However, it is not the higher quality bosch pump.

I can hear my pump while standing OUTSIDE the cab, if my tank is not full and it is quite outside.

Try parking it in different locations (with the engine on and in park) and see if the noise level is the same. Sometimes depending on where I park, I can hear my pump more (maybe the pump is submerged more or less depending on parking position?) .

 

I hear my 255LPH pump as well, but I think it is functioning properly and without issue.
I could hear my stock one and the 190LPH I had as well.
That big pump is loud and I have really good hearing.

 

I don't think you are supposed to hear the pump. This means that the bearing could be getting energized by lack of proper grounding. Mad has a rubber kit you can use to insulate you pump from the bracket itself. Just a guess from what I read in the past.

Bill

 

I did use the rubber kit and insulate it but i never could get infinite resistance. I was just curious if i should worry i'll try and call him this week and talk about it.

 

well i can hear the humm loud and clean in the cab or out the truck all the way around! Today merging on the highway she was under boost and started to spuder, each time the fuel pressure would drop to almost 0! Could this be related or something totally different?

 

I had a similar problem, But I found that I didn't put the fuel pump low enough and was sucking air at just below 1/4 tank. Check your fuel filter and hoses make sure you didn't bind anything. It sounds like fuel starvation if you are hickuping and pressure drops. The pump could be failing and or you have a blockage in the line somewhere that is causing it to work overtime. Also I can hear my pump when I turn the key on and the system pressurizes but after that I hear nothing it is really quiet. I have walked around my truck and I don't hear the pump.

Bill

 

well i just changed the fuel filter last week to see if it would quiet the pump some (didn't work) and this is happening on a full tank. I'll get with Mike tomorrow about a replacement, the only thing that has me puzzled is Mike mentioned this has only happened once before and it was due to improper installation.

 

I clearly hear my pump from the driver side of the truck.
But, I also heard the Walbro 190LPH pump that came with my previous Allen kit.
I've gone beyond Mad's rubber isolation kit and added additional rubber padding and there is no place on this pump that touches metal (cradle, clamps, tubes,,,etc)
No hickups at all so far.

Now, this week will really be the test if things are installed right.
I FINALLY got my fuel guage working correctly (after two attempts).
Before when it wasn't working, the truck would sputter and I knew it was time to fill up. Sure enough, it took 24.4 gallons ($65 of premium gas in Calif!). So the pump is at the right level in the tank.

I sure don't want to pull the tanke a fifth time! Next time I pull the tank, the Lightning fuel pump assembly is going in. Mad has an interesting plan (idea) on how to make this work in the non-L trucks!

This is one of the more interesting threads I've seen in a while.
Thanks for sharing.

-adam

 

Parked and at idle you should see 34 to 35 lb of pressure and with the vacume line od 38-39 lb of pressure.


Suavy

 

Suavy is that with the bosch 255 or the stock dual pump lightning setup?

 

That's the pressure I see at idle as well.

 

Well it is progressively getting worse! Looks like the fuel pump is taking a dive. i can't even go WOT anymore, BUT i have a replacement coming thanks to Mike!! Hopefully everything will be back to normal ( or at least what i consider normal ) by next week!

How much pressure are you guys seeing WOT at about 10 or 11 psi boost?