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95DieselBurb
01-13-2019, 20:17
Looking for any suggestions y'all might have for a cost-effective aftermarket low pressure fuel gauge to monitor the output of the lift pump in a '95 K1500 Suburban with 230k on a 6.5 recently. Previous owner had replaced pretty much the entire fuel system from tank to IP (not sure about injectors themselves) but it wouldn't run. My son looked at it for me (was closer to him than me) and diagnosed two problems: (1) no power to the new lift pump and (2) a nick in the PMD relocation cable. I replaced the PMD cable and drove it home with a jury-rig hotwire powering the lift pump (used a 16ga extention cord straight to the battery). Still have to troubleshoot the open circuit (suspecting bad ground) but want gauge for piece of mind anyway.

arveetek
01-14-2019, 15:31
At the very least, go with a liquid-filled gauge. The pulsating nature of the lift pump destroys a standard gauge pretty quick. I have two Mr. Gasket liquid-filled gauges on my '95 (one before the fuel filter and one after). Neither one goes back to zero anymore, but at least I can tell I have pressure! I'd suggest a good quality brand, such as Isspro or Autometer.

Casey

N9Phil
01-15-2019, 06:05
I have a vacuum/pressure gauge connected to the water drain hose from the filter. If I suspect a pump problem all I have to do is lift the hood and check the gauge while the engine is running. I leave it connected and set off to the side. If I suspect water in the fuel I disconnect the hose from the gauge and drain any water this way. Have had this connect this way for more than 5 years with out any problems.

95DieselBurb
01-15-2019, 08:14
...good points both. arveetek, did you run your gauges inside the passenger compartment (realizing that is a safety no no, but it is diesel, not gas) also, do you think an electric gauge would hold up better and, if so, any thoughts/experience with specific brands?

N9Phil, the water drain was my thought, too, as an easy access point. So you just leave the gauge hooked up with the valve closed and only consult it when you suspect a fuel problem?

While we're on the subject of fuel supply, what are your thoughts regarding the oil pressure sensor safety switch being in the circuit. Bearing in mind that we're dealing with diesel, seems like just one more unnecessarily complicated potential failure point mandated by overzealous safety Nazis. Have y'all made any improvements in that setup?

N9Phil
01-16-2019, 05:32
I only have the gauge hooked up, if I need to check for water etc I just disconnect the hose from the gauge. Kennedy Diesel has a set up to solve the problem. https://www.kennedydiesel.com/detail.cfm?ID=402

DmaxMaverick
01-16-2019, 08:25
......While we're on the subject of fuel supply, what are your thoughts regarding the oil pressure sensor safety switch being in the circuit. Bearing in mind that we're dealing with diesel, seems like just one more unnecessarily complicated potential failure point mandated by overzealous safety Nazis. Have y'all made any improvements in that setup?

Not recommended, and not legal. With a very rare exception of an emergency or diagnostic purpose, the fuel lift pump, of any motor fuel, must be controlled, and should never be forced to run when the engine is not running or during a start cycle. While it is fair to say the Diesel fuel is generally less volatile than gasoline, it is not necessarily less unsafe, more safe, or less combustible than gasoline, at the time the necessity of the fuel lift pump control is realized. A vehicle fire doesn't care what fuels it, and at the temperatures involved, before any motor fuel is introduced (what's in the tank isn't the only fuel present, and is less often the first to combust), the volatility differences are minimal contributors to the extremes of a vehicle fire. All vehicle fires progress the same, and conclude the same, with the only difference being the rate of progression and when they are extinguished. A fuel lift pump only moves fuel from one place to another. The longer that fuel remains at a greater distance from the primary heat source, the greater is the survivability of all parties involved. I really can't put it more delicately than that. Please understand the reasons, and take responsibility. Vehicle accidents are called accidents for a reason. You don't get to choose the time and conditions. The best we can do is minimize factors under our conscious control that contribute to the progression of an horrific incident.

arveetek
01-16-2019, 08:48
...good points both. arveetek, did you run your gauges inside the passenger compartment (realizing that is a safety no no, but it is diesel, not gas) also, do you think an electric gauge would hold up better and, if so, any thoughts/experience with specific brands?

While we're on the subject of fuel supply, what are your thoughts regarding the oil pressure sensor safety switch being in the circuit. Bearing in mind that we're dealing with diesel, seems like just one more unnecessarily complicated potential failure point mandated by overzealous safety Nazis. Have y'all made any improvements in that setup?



I'm using an aftermarket Racor fuel filter setup, and plumbed the gauges directly into the inlet and outlet of the filter housing. I have to open the hood to look at the gauges:



https://farm6.staticflickr.com/5663/31183352212_8e99c67582_b.jpg


I don't have any experience with the electric gauges, so I can't comment on that.

I use Kennedy's OPS harness. It's over 13 years old and is still working great!

http://www.kennedydiesel.com/detail.cfm?ID=402

Casey

95DieselBurb
01-16-2019, 18:32
...(and duely noted and chastised, Dmax Maverick)

Arveetek, I like your dual guage setup on the Racor. Do you happen to have the Racor model number for the housing and how involved was it plumbing it in?

DmaxMaverick
01-16-2019, 20:11
...(and duely noted and chastised, Dmax Maverick)....

I didn't mean to chastise, and it wasn't directed at you specifically. This comes up every couple years, and I just drive the message hard. I can't control what you do, but I can contribute to what you know, and hope you'll use the information appropriately.

95DieselBurb
01-16-2019, 20:27
No offense taken....what kind of MPG numbers did the Cruze generate?

DmaxMaverick
01-16-2019, 21:39
No offense taken....what kind of MPG numbers did the Cruze generate?

Solid mid 50's average. We had a few highs around 70 in ideal conditions, and 60-65 was regular on fair weather highway trips. It was never below the EPA estimates. In town driving was better than the estimates, but not as spectacular.

JohnC
01-17-2019, 06:48
Man, I wish they'd build something similar with 3 row seating...

DmaxMaverick
01-17-2019, 08:10
Man, I wish they'd build something similar with 3 row seating...

Didn't they? Or was that sarcasm?

arveetek
01-17-2019, 09:42
Arveetek, I like your dual guage setup on the Racor. Do you happen to have the Racor model number for the housing and how involved was it plumbing it in?


I don't recall the exact model number... it's been several years. I think this one may actually be discontinued! But it wasn't hard to plumb in. I cut the fuel line that comes up from the frame rail and then ran a new line from there, to the filter housing, and then a new line from the filter housing to the IP.

Casey

JohnC
01-17-2019, 18:19
Didn't they? Or was that sarcasm?

No, serious. There's Cruz, Equinox and Colorado with small Diesels, but none of them have third row seating. It would have to be a Traverse to get the third row, and there's no Diesel option there.

Trail Blazer/Envoy/Bravada used to be based on something similar to the Colorado, which has a Diesel option, but they were apparently dropped in favor of the Traverse.

:mad: