I'm sick of my isolator that goes to my ispro fuel pressure guage. Every so often I get low readings and I have to push back the rubber thingy in the isolator and fill it back up to get it to read right. Would it be safe to eliminate the isolator and have diesel go all the way to the gauge?

Yes, a lot of us have been running them this way from the gitgo. Make sure you get yourself a 1/8 needle valve, Napa used to carry weather head 6820 but they recently switched to gates and they don't work. Eric at http://www.vulcanperformance.com/SearchResults.asp?Search=Needle+valve&Submit=

can send you one

Edited July 29, 20159 yr by 98whitelightnin

I'm assuming you put the needle valve in place if the isolator so you can shut of the fuel if needed. What's the best way to bleed off air at the gauge?

Put the needle valve at the source of your fuel tap then if anything goes wrong you can shut the entire system down. The run 1/8" air brake tubing from the needle valve to the gauge. Longer the run the better. I ran direct plumbed for 10 years and with a needle valve. Today I still got the needle valve but not used for dampening any longer it's use as a shut off device for system leaks or failures. I'm using a ISSPro snubber with my ISSPro EV2 electric gauges.

I use an Ashcroft gauge snubber, pricey but used in nuc plants

Remember all shut off valves and snubber should be installed right at the tap point of the fuel system. Now coupled with the length of run to the sender or gauge will give even more dampening ability to the system. Do not use a grease gun hose! Keep line size down to small line sizes like 1/8" tubing will help but make the run longer than 5 feet if possible. I found one member than used 1/4" air brake and it did not dampen the water hammer it actually past it along to the gauge.

I used a oil filled pressure gauge from McMaster Carr. Not needing to watch it all the time, I mounted it on the floor to the right of the fuel pedal. Ran 1/4 inch air brake tubing to pump. Oil fill gauge needs no snubber.

I put in a needle valve it works great.Thanks.Next job is to take out the dash and fix my ac evap and heater core while I'm in there.

  On 8/7/2015 at 4:36 AM, lrhull said:

I put in a needle valve it works great.Thanks.Next job is to take out the dash and fix my ac evap and heater core while I'm in there.

 

Got you covered.

I'm running Isspro EV2, put sending unit at pump (DDRP) on frame rail, that was at least 3 years ago. no snubber, no needle valve, no damping of any kind and no problems.

  On 8/7/2015 at 2:11 PM, mehbohdi said:

I'm running Isspro EV2, put sending unit at pump (DDRP) on frame rail, that was at least 3 years ago. no snubber, no needle valve, no damping of any kind and no problems.

 

That's really bold...   I still wonder how long it will hold accuracy? Have you tested for accuracy?

  On 8/7/2015 at 2:16 PM, Mopar1973Man said:

That's really bold...   I still wonder how long it will hold accuracy? Have you tested for accuracy?

So far I still have the same hi and lo's I had when installed. Everything was installed at same time ( pump, gauge, and big line kit). My thinking is, because the sending unit is at the pump and it is rubber hose all the way to VP the rubber is absorbing some of the hammering. That's the only explanation I have. I'd rather be lucky than good...

Edited August 8, 20159 yr by mehbohdi

I'm also 1/2 inch rubber hose from the fuel tank to the VP44. Then another 5 foot of 1/8" air brake line from the tap point into the cab on the old mechanical gauge and it used to buzz if the needle valve wasn't set right. So even with the change over I'm still 5 foot of tubing to the sender but have the snubber and needle valve at the tap point. Lot of people are wrapped up in the myth of using grease gun hoses will either suppress water hammer or suppress vibrations. Hate to say it it does nothing for either senders still fail...

I will update post if sending unit ever fails. I don't drive mine more than 10,000 miles a year so it might take awhile.

  On 8/12/2015 at 1:22 AM, mehbohdi said:

I will update post if sending unit ever fails. I don't drive mine more than 10,000 miles a year so it might take awhile.

 

Hmmm... I'm right around 30k miles a year.