Author Topic: Fuel Pressure Gauge  (Read 32113 times)

Offline Stewart G Griffin

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Re: Fuel Pressure Gauge
« Reply #30 on: January 15, 2009, 09:54:58 pm »
That's certainly an interesting approach.  So, you run no mechanical pumps on this truck whatsoever?

Offline HAULIN IT

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Re: Fuel Pressure Gauge
« Reply #31 on: January 16, 2009, 10:35:17 am »
No mechanical pump Stewart, I just made a plate to cover the hole. Lorne

Offline Stewart G Griffin

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Re: Fuel Pressure Gauge
« Reply #32 on: January 16, 2009, 10:39:52 am »
PT.2

OK, next i need to know what size exactly is the inverted flare nut that goes into the fuel inlet nut (chevy, BOP/"big" nut), not the line itself.  i know the line is 3/8.



And not what size wrench either to use on the nut, i'm talking about the actual threaded part that screws into the inlet nut.  i've already ordered two flares from jeg's in order to make up the new line to install a pressure gauge and they both don't fit-----5/16 and 3/8.

b) Do all V-8/6 carbed Gm cars from say, 65ish to 87-90ish basically run the same flares on the carb and pump sides?   i may just try a salvage yard at this point and just cut into it (although now this poses a problem because of the metal shavings) and just make up a line from that.

« Last Edit: January 16, 2009, 11:37:30 am by Stewart G Griffin »

Offline HAULIN IT

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Re: Fuel Pressure Gauge
« Reply #33 on: January 16, 2009, 01:27:45 pm »
Stewart, That is what is called a 3/8" tubing nut. Which is different than 3/8" NPT or 3/8" bolt tread (fine or coarse). To get something to thread into & seal, it has to be a fitting for "3/8" tubing to ?". Not what you want, but as an example, a 3/8" tube to rubber hose (barbed end) brass fitting exists & so forth. This is the reason I make allot of my fittings... by the time you get to what you want, you have a thing that looks like a pile of fittings from a junk drawer. Yes all of what you listed will be the same nut/line size.
 Are you wanting a permanent pressure gauge? What are you planning to use for a gauge & where are you planning to mount it? Lorne     

Offline Stewart G Griffin

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Re: Fuel Pressure Gauge
« Reply #34 on: January 16, 2009, 05:58:08 pm »
1) OK, so now i'm completely confused.
a) At this point, could somebody provide a part# that will accomplish what i'm trying to do?  A/N or whatever is fine as long as it works.

2) If all GM's pretty much use the same fittings, i may try the salvage yd. route and use compressed air to blow out the small shavings.

3) No, this is just a temporary line for testing the pump and any other occasion when i would need to test a pump.  i got one of those liquid filled Jeg's brand mechanical gauges that will mount off a "T" fitting near the carb.  Here is what i've come up with so far:



Everything to the left of the gauge and "T" fitting, which both came in on wed, is what i found laying around in my parents' garage from a previous project----looooong story.  i don't even remember if i made it or the shop i eventually went to constructed it.  The shop was actually Malcolm Durham's.  Anyways, to the far left, we see a part of stock line which was cut into leading to the rubber connectors and so forth.  All i need is a 3/8 barb and something that will screw into the inlet nut on the carb.

As for a permanent gauge, when i get time to research it and do it right, i would ultimately like an electric gauge that can stay inside the cab as opposed to on the hood which is cool, but this is a street driven truck, not a racer, so i feel inside is better.  And then, of course, i feel that the best way for the gauge to feed off of(get signal) would be to slightly bend the stock line so that there is space between the tubing nut and the inlet nut and then appropriate adapter nuts/fittings can be used to join the two with a "T" fitting in between.  This way it's leak free and safe as stock.


Offline frogman68

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Re: Fuel Pressure Gauge
« Reply #35 on: January 16, 2009, 07:59:20 pm »
1) OK, so now i'm completely confused.
a) At this point, could somebody provide a part# that will accomplish what i'm trying to do?  A/N or whatever is fine as long as it works.

2) If all GM's pretty much use the same fittings, i may try the salvage yd. route and use compressed air to blow out the small shavings.

3) No, this is just a temporary line for testing the pump and any other occasion when i would need to test a pump.  i got one of those liquid filled Jeg's brand mechanical gauges that will mount off a "T" fitting near the carb.  Here is what i've come up with so far:



Everything to the left of the gauge and "T" fitting, which both came in on wed, is what i found laying around in my parents' garage from a previous project----looooong story.  i don't even remember if i made it or the shop i eventually went to constructed it.  The shop was actually Malcolm Durham's.  Anyways, to the far left, we see a part of stock line which was cut into leading to the rubber connectors and so forth.  All i need is a 3/8 barb and something that will screw into the inlet nut on the carb.

As for a permanent gauge, when i get time to research it and do it right, i would ultimately like an electric gauge that can stay inside the cab as opposed to on the hood which is cool, but this is a street driven truck, not a racer, so i feel inside is better.  And then, of course, i feel that the best way for the gauge to feed off of(get signal) would be to slightly bend the stock line so that there is space between the tubing nut and the inlet nut and then appropriate adapter nuts/fittings can be used to join the two with a "T" fitting in between.  This way it's leak free and safe as stock.



Go to Home Depot or any hardware store and ask for a 3/8 tube fitting

Offline 85MudMonster

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Re: Fuel Pressure Gauge
« Reply #36 on: January 16, 2009, 08:34:33 pm »
I think I'm lost...what are we trying to do here?
Dan

85 Chevy K10 - 408 BBC from a 71 Chevelle SS, TH350, NP208, 33" Mastercraft Courser M/T

Offline joesgarage71

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Re: Fuel Pressure Gauge
« Reply #37 on: January 16, 2009, 08:51:09 pm »
Steward,
 You can get the flare nut at any parts store. Just ask for a small section of 3/8 line with nuts. They sell them (like brake line) in all kinds of lenths. You'll get two nuts and the line with double flares.
 Steve
78' K-20 355/SM465/twin stick 205 6" on 36's
14 bolt FF/big bearing Dana 44 4.56 gears

92' GMC C-1500 454/4L80E/14 bolt

Offline Stewart G Griffin

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Re: Fuel Pressure Gauge
« Reply #38 on: January 17, 2009, 02:31:15 pm »
Ok, thanks for the link;  It looks like the brake line idea will work.

85MM, i will get a picture up as soon as i finish the project, maybe a picture can explain it better than words.

Offline Stewart G Griffin

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Re: Fuel Pressure Gauge
« Reply #39 on: January 18, 2009, 11:44:43 am »
i got 24" of 3/8 brake line at advance auto last night for $2.50, so a big thank you to steve.

Offline joesgarage71

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Re: Fuel Pressure Gauge
« Reply #40 on: January 18, 2009, 12:15:23 pm »
 Your welcome sir
78' K-20 355/SM465/twin stick 205 6" on 36's
14 bolt FF/big bearing Dana 44 4.56 gears

92' GMC C-1500 454/4L80E/14 bolt