Engine/Transmission (1998.5 - 2002) More Fuel Pressure Gauge Questions

[rakm]

I'm currently considering using a boost gauge for my fuel pressure.





1. Is someone absolutely sure that this is a valid option? I've had some say these gauges aren't rated for liquid (especially diesel) and could cause problems and others say thats totally inaccurate and wont cause any problems...



2. Are the grease gun hoses ok to use for delivery? Some say that they work fine at first but could cause problems later on from breakdown and leaching into the fuel system.



3. What about copper tubing? Is it ok or will it become to brittle over time and vibrations from the engine? Smack a piece of copper tubing against a workbench and see what happens, it get very inflexable. .



4. I was told that if used on the right fittings teflon tape is ok to use as it wont be in contact with the diesel anyways. <i>Teflon is supposidly used to be able to tigten the fittings furthur without binding and NOT to actually seal the fittings. Its more to allow to fittings to turn tighter with less binding with the teflon as the lubricant, so to speak. </i> This actually makes sense if you really think about it.



5. Can a mechanical be mounted in a pillar pod?

 

[BILLUA]

1) NO!!!



2) I don't know about the long term effects. I had a steel line braided hose 24 inches long made up for 25 dollars.



3) No



4) you are correct use pipe dope only on upper threads



5) Absolutely not!!!



6) Spend the extra money and buy a west tach fuel pressure gauge from Geno's garage with isolator and do the Job right before you fill your cab with diesel!



Cheers!

 

[BFC]

Ramk,



Sure is an option 'cause I run one, over a year not a single problem. The boys at Autometer told me it was cool to use a boost gauge for fuel pressure. I have mine set up with all Aeroquip fittings and -4 SS braided hose. Works like a charm and it is reliable. I mounted it under the dash next to the center humps in a single pod, I can take a pic if you'd like.



Call Andy at www.smokindiesel.com (724-335-6167)



He will take care of you, explain all the different options for YOUR application. Whatever concern you may have he'll give it to you straight. I got my set up from him, never been sorry.



My 2cents,



Glenn



You can alway use an isolator if fuel in the cab worries ya, don't bother me.

 

[rakm]

Fuel in the cab isn't a concern for me. I don't think it would ever develop to be more than a small drip for a leak inside the cab, if anything. Danger wise, I just don't see any potential.



Billua,

You say no for numbers 1,3 and 5. Any explainations as to why these are problems?



BFC:

I'm probably going with something very similar for my setup. Autometer boost 30psi and Stainless braided. BTW stainless braided is simply plastic/rubber tubing wrapped in stainless. So as far as the diesel ratings, if there is one, you would be looking at the same questions over a long period of time for the fuel system as you would with grease gun tubing. Will the plastic /rubber break down over a period of time?



The reason I ask about the breakdown is an experience I had with Rotella DFA.

I put it in cleaned out smaller plastic bottles that used to carry the STP diesel treatments. Well after two weeks the bottles were very MUSHY/soft. Just made me start thinking about the compatability issue... .

 

[Huff N Puff]

An Air Conditioning line works great

Its already got the schrader valve fitting made onto it, the hose is more than adequeate for the pressure and its oil resistant. You'll need a pipe to hose adapter on the gauge end. Merv

 

[illflem]

Over five years with a mechanical gauge in the cab with no leaks or problems. A boost gauge will work fine, many have done it. I use a $9 water pressure gauge. I've used the plastic line that comes with a boost gauge on several rigs, a couple in the pillar, no problem. I think with five years if it wasn't compatable with diesel it would have leaked by now. Just pass it though 1/4" tubing to prevent kinks and cuts from sharp edges. Don't reef down on compression fittings with plastic tubing, it will only distort the ferule and leak. Copper tubing is too inflexible, engine vibration and movement would tend to break it. A GG hose shouldn't be necessary with a mechanical gauge, they are used mainly with electric senders to isolate them from engine vibrations. My feeling is the simplest way to do something is often the best. SS line may look cool but is a total overkill and very difficult to route into the pillar.



I feel it's good idea to install a 1/8" needle valve as close to the pressure source as possible. You can then run the valve almost closed to keep any potential leaks very small and have the option of shutting it down if one occurs.



Teflon tape doesn't work with diesel, it will eventually leak. What's even worse is if you have to redo a fitting the tape debris is almost impossible to remove without contaminating the system. Anti-seize is a much better choice, it is made with fine ground soft metal such as aluminum, copper or lead that will fill the voids, act as a cushion and lubricate much the same as Teflon tape.



In my opinion a mechanical gauge is the only way to go for reliability, it's very rare for one to screw up. Nine times out of ten when you get a warning reading from an electrical gauge the problem is with the sender or wiring, not the system you're monitoring. 2¢

 

[Rob Thomas]

Ditto to what illflems said,



My mechanical gauge's ( pre and post filter) are in the a-pilar, although I used SS braided line to the gauge's and a grease-gun hose from the filter housing for about a foot, to kill the vibration from the SS lines.



I also agree mechanical gauges are the way to go, for reliability, and accuracy, it's instasnt (like a tach) no senders to relay from.



Later, Rob

 

[andrewkoperdak]

When I was looking for piece parts to install my gauge, I read the application note on a grease gun package. It said that the grease gun hose was only designed for grease. Nothing else. Diesel, kerosene and home heating oil destroy rubber components.



Having said that... I know that there are several sections of rubber tubing in our fuel systems. Maybe that is why I have leaks at 30K miles!



andy

 

[mikeberry]

No problem with the mechanical. I removed the 4" rubber line between the filter outlet, and the injection pump. I used a tubing bender to re-align the metal line from the filter banjo fitting on up so it is now next to the filter housing,(about 6" rearward from its stock location. ) I then used new 5/16 fuel line to put a "t" in between the filter and inj. pump. from the "t" I ran a 5/16 fuel line to a needle valve. I secured the valve and attached copper line to something that won,t shake so bad. (the isolation factor provided with the rubber fuel lines also helps. ) I have all three gauges mounted in an autometer a-pillar pod. The gauges are all autometer pro-comps. Work great!

In terms of a small oil (diesel) leak in the cab, Hey we all ran 200+ degree 30 weight into the mechanical oil gauges in the cabs of our hot rods in high school didn't we? like ILLFLEM said that's what the needle valve is for.



Just my thoughts it's your money and your truck.