Fuel pressure idiot light

[Texas Diesel]

I wanted something to alert me to a low fuel pressure problem before I happened to check the gauge. I put a "T" fitting at the gauge sender and put a mid 80's GM oil pressure switch there. This switch makes contact (with electrical ground) at 5PSI. I ran a wire to a red light (radio shack) which I mounted in my A pillar pod. The positive side from the light goes (through a fuse) to a ignition switched circuit. I have part#'s for switch and light if needed. I will attach a couple of shots, please ignor the sloppy wiring but it was getting dark, I'll fix it tomorrow.

 

[Texas Diesel]

Idiot light

 

[HEYBOSS]

Hmm... I wonder what effects diesel fuel has on that oil psi switch?



pertty

 

[EMDDIESEL]

what part of the engine compartment is that picture from. All i can make out is the senders

 

[Texas Diesel]

I doubt it will have any effect. These senders are usually constructed with a metal bellows type of chamber, the spring and contacts are on the "dry" side. Plus they are designed to take 100+ PSI when starting a cold engine. I've never seen one leak.

 

[Texas Diesel]

The engine compartment shot was with the camera sitting on the battery looking towards the master brake cylinder and enough zoom to fill the frame.

 

[Grandpappy]

Idiot light?

Hey guy, I just sent you a PM about my fuel press. gauge. I wish I had thought of your way for a warning light. My gauge works great, has adj. warning light, 0-20# range but it cost me an arm and a leg and had to be special ordered from Westach. BTW... . you want me to send you one of my "high tech" mounting brackets so you can mount the sender on the firewall ?

 

[HEYBOSS]

I really don't know if diesel fuel would have any affect on the switch. These GM switches were notorious for oil leaks, so I would imagine with fuel would even be worst. Good idea, I like It.

 

[Texas Diesel]

GRANDPAPPY: let me think about... uh... YES!!!!!!!!!!!!!!!!

 

[Texas Diesel]

FRodrigues: It is not a GM part, I wouldnt insult my Dodge by installing a GMC ( get my chain ) part, it is an aftermarket unit made by NIEHOFF for GM applications. You are correct about GM units leaking.

 

[EMDDIESEL]

If it can handle motor oil, it can handle diesel fuel. I would not worry. Most senders are petroleum resistant, meaning ALL types of petroleum.

 

[HEYBOSS]

Well I think you should refrase that an aftermarket unit made by NIEHOFF for Cummins applications.

 

[Bigsaint]

Real cool !!!! If any of y'all are riding the fence on SPA's, they have the 'idiot light' built right in, you just program the gauge at whichever low range you desire. Nice job, TX Diesel.



Scott W.

 

[WeirCummin]

idiot light, George I thought you were brighter than that. Just kidding, good idea. Oh by the way how much HP and smoke is that desk putting out now and are you installing a light on it as well. Its a private joke guys.

 

[Texas Diesel]

Dean, the desk doesnt smoke at all, probably a bad lift pump. I cant seem to find the lift pump to check it though

 

[Archive]

I did this mod. a couple of months ago. I used a berg switch from an 18 wheeler braking system good for operating pressures up to 150psi. The switch is "normally closed" with a 4psi activation pressure. It's mounted on the outlet side of the fuel filter. (I have a firewall mounted underhood fuel pressure gauge plumbed into the prefilter port. ) The berg switch is Volvo truck part #3972560. TRUE gearheads look down their nose at warning lights, but I didn't want to add another gauge. BigSaint makes a very noteworthy observation about the SPA's. Check your budget and BOMB accordingly.

 

[Texas Diesel]

Idiot lights equipped with redundant senders make good backups to gauges. At least your sender is from a "real" truck, mine is off a (gasp) GM . But my whole add on was less than $10. Will the tinkering and modifying ever end?? I have 275RV's sitting here on my desk... Pretty soon I'll have more in "necessary accessories" than the truck cost

 

[GDouglas]

Texas Diesel, I like your acronym for GMC LOL! The one I have always used was Gotta Mechanic Comming!

 

[EMDDIESEL]

Auto meter makes a series of "Pro Lights". I just bought one with a 15psi oil pressure sender. They have different color choices too. They have 2 sizes, 2 colors of housings and they also have an LED version. www.autometer.com