fuel pressure questions

action1w · 07-14-2008, 10:52 PM

Hi all need some help?

just installed ISSPRO mechanical fuel pressure gauge in my truck. 98.5 24 valve 2500 2wd

it reads 11-12 at idle...
When I drop the hammer the gauge never moves?

Installed in the "hole" closest to the block on the top of the fuel filter. Have a fuel stuber installed then a 1/4 copper compression to isolator valve. Then to the gauge. the line, gauge side of isolator and the gauge itself is filled with the 50/50 blend of antifreeze.

I burped the fuel side and the antifreeze side but still the gauge does not move. tach was at 3200 comp box on 4 smoke level at 4 also running stage 2 injectors and and a very large K&N Filter.

Brad

diesel6.7 · 07-15-2008, 05:42 AM

those mechanical gauges can be tricky, are the isolator and fuel gauge at the same level?

action1w · 07-15-2008, 07:16 AM

There close, Isolator is mounted on the firewall next to the main wiring loom. The gauge is mounted were the passenger air bag switch was. ( tuck that switch in the dash and custom made my own face plate.

Brad

diesel6.7 · 07-15-2008, 01:49 PM

did you bleed fuel from the filter housing to the isolator?

TheNatural31 · 07-15-2008, 02:04 PM

You say you have it connected on top of the filter? I would connect to the schrader valve on the VP!! Thats the reading that is most important and if you are reading 11-12 pre filter you may need to upgrade that LP with the mods you have!!

__________________
01 2500 4x4..NV45..3.55's..VanAaken Smartbox..BHAF..plugged wastegate..SR/MIA.. 5" FBD/TBE..Vulcan Big Line Relo Kit & Draw Straw..Holly Blue..Dipricol boost,pyro Fuel Pres..BD short/shifter..scanguageII..

.It May Not Be FAST, But It's BULLETPROOF!

action1w · 07-15-2008, 07:51 PM

Quote:

Originally Posted by diesel6.7

did you bleed fuel from the filter housing to the isolator?

Yes bled the fuel side and the gauge side. I also noticed that some pictures have the gauge horizontal and some have it vertical, is there a perferd method of attachment.

I can post pictures if that would help also.
Brad

action1w · 07-15-2008, 07:54 PM

Quote:

Originally Posted by TheNatural31

You say you have it connected on top of the filter? I would connect to the schrader valve on the VP!! Thats the reading that is most important and if you are reading 11-12 pre filter you may need to upgrade that LP with the mods you have!!

I pulled the banjo fitting off the VP and there appears to be a spring with a check ball in that fitting, not sure what that was for, original plan was to drill and tap the banjo fitting for 1/8" pipe threads, however when I seen that I put it in the filter hole closest to the block.

Brad

John Deere Matt · 07-15-2008, 08:07 PM

does your line between the filter and the pump even have the schrator valve on thr inj. pump end

__________________
2006 2500 Cummins quad cab long box afe stage 2 intake, quadzilla boost fooler, and smarty.looking for more
also have a 1992 w250 turned up and a tighter exaust housing on the turbo

***MCummings*** · 07-15-2008, 08:08 PM

Quote:

Originally Posted by TheNatural31

You say you have it connected on top of the filter? I would connect to the schrader valve on the VP!!

There's no schrader valve on '98.5 and '99 Cummins!!

Merrick

__________________
Merrick Cummings Jr
'98.5 3500 2wd 6-speed
4-wheel peel thanks to South Bend Clutch. 512/1021 and 21MPG.
Hers,
'98.0 2500 4wd Auto, new recon motor, trans no worky, 5.5" Lift, Straight pipe.

diesel6.7 · 07-16-2008, 06:33 AM

Quote:

Originally Posted by action1w

Yes bled the fuel side and the gauge side. I also noticed that some pictures have the gauge horizontal and some have it vertical, is there a perferd method of attachment.

I can post pictures if that would help also.
Brad

show some pics, that way there is no confusion.....

speedntriple · 07-16-2008, 07:03 AM

could be the gauge, I used to have mine on top of the filter housing and it worked fine, now its in the fitting on the 1/2 fuel line and still works great...

__________________
99 QCLB 4x4 5spd, 5" str8, Southbend Clutch, AFE w/Outerwear, AirDog 150, Banks High Ram, Edge Drag Comp, Autometer gauges,DSS, Ranchand steps & front & rear, MotoMetal wheels,tinted, Pioneer CD/DVD, speakers. Weatherguard Toolbox, spray in liner...

action1w · 07-16-2008, 07:37 PM

here are the pictures I have taken hope this clears things up a bit.

Thanks again for the help.

Brad

Attached Images

	fuel_pressure_isolator_2.jpg (31.0 KB, 10 views)
	fuel_pressure_isolator_1.jpg (46.3 KB, 10 views)

07-14-2008, 10:52 PM	#1 (permalink)
action1w Newbie Join Date: May 2008 Posts: 16 action1w's Truck Pics	fuel pressure questions Hi all need some help? just installed ISSPRO mechanical fuel pressure gauge in my truck. 98.5 24 valve 2500 2wd it reads 11-12 at idle... When I drop the hammer the gauge never moves? Installed in the "hole" closest to the block on the top of the fuel filter. Have a fuel stuber installed then a 1/4 copper compression to isolator valve. Then to the gauge. the line, gauge side of isolator and the gauge itself is filled with the 50/50 blend of antifreeze. I burped the fuel side and the antifreeze side but still the gauge does not move. tach was at 3200 comp box on 4 smoke level at 4 also running stage 2 injectors and and a very large K&N Filter. Brad

07-15-2008, 02:04 PM	#5 (permalink)
TheNatural31 Cummins Fanatic Join Date: Apr 2008 Location: College Station/Kingsville, TX. Posts: 168 TheNatural31's Truck Pics	You say you have it connected on top of the filter? I would connect to the schrader valve on the VP!! Thats the reading that is most important and if you are reading 11-12 pre filter you may need to upgrade that LP with the mods you have!! __________________ 01 2500 4x4..NV45..3.55's..VanAaken Smartbox..BHAF..plugged wastegate..SR/MIA.. 5" FBD/TBE..Vulcan Big Line Relo Kit & Draw Straw..Holly Blue..Dipricol boost,pyro Fuel Pres..BD short/shifter..scanguageII...It May Not Be FAST, But It's BULLETPROOF!

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07-15-2008, 05:42 AM	#2 (permalink)
diesel6.7 Cummins Fan Join Date: Apr 2008 Location: phoenix Posts: 61 diesel6.7's Truck Pics	those mechanical gauges can be tricky, are the isolator and fuel gauge at the same level?

07-15-2008, 07:16 AM	#3 (permalink)
action1w Newbie Join Date: May 2008 Posts: 16 action1w's Truck Pics	There close, Isolator is mounted on the firewall next to the main wiring loom. The gauge is mounted were the passenger air bag switch was. ( tuck that switch in the dash and custom made my own face plate. Brad

07-15-2008, 01:49 PM	#4 (permalink)
diesel6.7 Cummins Fan Join Date: Apr 2008 Location: phoenix Posts: 61 diesel6.7's Truck Pics	did you bleed fuel from the filter housing to the isolator?

07-15-2008, 08:07 PM	#8 (permalink)
John Deere Matt Cummins Fan Join Date: Feb 2008 Location: central wisconsin Posts: 50 John Deere Matt's Truck Pics	does your line between the filter and the pump even have the schrator valve on thr inj. pump end __________________ 2006 2500 Cummins quad cab long box afe stage 2 intake, quadzilla boost fooler, and smarty.looking for more also have a 1992 w250 turned up and a tighter exaust housing on the turbo

07-16-2008, 07:03 AM	#11 (permalink)
speedntriple Cummins Fan Join Date: Sep 2007 Location: dublin, va Posts: 83 speedntriple's Truck Pics	could be the gauge, I used to have mine on top of the filter housing and it worked fine, now its in the fitting on the 1/2 fuel line and still works great... __________________ 99 QCLB 4x4 5spd, 5" str8, Southbend Clutch, AFE w/Outerwear, AirDog 150, Banks High Ram, Edge Drag Comp, Autometer gauges,DSS, Ranchand steps & front & rear, MotoMetal wheels,tinted, Pioneer CD/DVD, speakers. Weatherguard Toolbox, spray in liner...