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Mechanical fuel pump connections

  • Thread starter Thread starter Edbert
  • Start date Start date May 9, 2005

Edbert

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Jul 13, 2002
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Austin TX
May 9, 2005
#1
  • May 9, 2005
  • #1
I have a Holley 110GPH mechanical fuel pump that did not come with instructions. All I need to know is which port is the inlet and which is the outlet.

Anyone?
 

rbohm

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Apr 12, 2002
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tucson,az
May 10, 2005
#2
  • May 10, 2005
  • #2
when you bolt the pump the the block you use the same outlets as you would for a stock pump.
 

Edbert

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#3
  • May 10, 2005
  • #3
I sent a request to Holley already, but they said it could be 48 hours before I hear back. I looked all over the thing for arrows and saw one underneath that points to the block, but the ports are fore and aft, so the arrow didn't help.

Here's what it looks like:
 

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Edbert

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#4
  • May 10, 2005
  • #4
I'm wondering whay this was moved to "talk", no wonder nobody knows, they're all in the gutter over here...LOL.
 
G

gjz30075

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#5
  • May 10, 2005
  • #5
Edbert, you can probably work the arm to find out which is the suction port.
 

jes72mustang

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Mar 31, 2005
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May 10, 2005
#6
  • May 10, 2005
  • #6
logic would tell me that the port to the rear( closest to the fuel tank) would be the inlet, and the front would be the output. Let us know what Holley has to say. Also did you check Holley's website for the documentation they have most of the stuff on-line.
 
F

ForceFed70

That's why they call it "dope"
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#7
  • May 10, 2005
  • #7
gjz30075 said:
Edbert, you can probably work the arm to find out which is the suction port.
Click to expand...


That's what I did with my pump.

Mount the pump in a vice and then work the arm. It'll be pretty easy to figure out which port is which by looking at which port is sucking in air and which one is blowing it out.
 

65fastback2+2

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Aug 4, 2003
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May 11, 2005
#8
  • May 11, 2005
  • #8
mine had the ports different or I would tell you for sure. If you bolt my holley fuel pump up and look at if from the side (like you would when mounting) there would be a port at 4 o'clock and one at 7 o'clock.
 

Edbert

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May 11, 2005
#9
  • May 11, 2005
  • #9
Thanks guys, since my 48 hour wait ( ) will be over today I'd just as soon NOT take the pump out to see for myself. The only reason I'm on hold for this in the first place is that I am making my braided lines and AN fittings, and I want them to fit EXACTLY.
 
F

ForceFed70

That's why they call it "dope"
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May 11, 2005
#10
  • May 11, 2005
  • #10
Edbert said:
Thanks guys, since my 48 hour wait ( ) will be over today I'd just as soon NOT take the pump out to see for myself. The only reason I'm on hold for this in the first place is that I am making my braided lines and AN fittings, and I want them to fit EXACTLY.
Click to expand...

If the pump is in the car, it's even easier. Just get someone to crank the engine while you use your hand to feal for the direction of airflow from the ports.
 

Edbert

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Jul 13, 2002
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May 11, 2005
#11
  • May 11, 2005
  • #11
Hahaha...that will be easy once I have an electrical system in her...LOL!



It is actually further along than this picture. I am working on getting the plumbing setup with the hopes of starting her up soon.
 

foghorn67

I'll save you the time and choke myself
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May 11, 2005
#12
  • May 11, 2005
  • #12
it wasn't marked on the bottom? I have the same pump, and it had in and out marked.
 

Edbert

Founding Member
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May 12, 2005
#13
  • May 12, 2005
  • #13
Did yours have arrows? I looked and saw nothing, but if there was a small "in out" word on there I might have missed it. The 48 hours came and went, nothing heard from Holley. Their 1-800 number is for ordering a catalog only.
 

foghorn67

I'll save you the time and choke myself
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May 12, 2005
#14
  • May 12, 2005
  • #14
Edbert said:
Did yours have arrows? I looked and saw nothing, but if there was a small "in out" word on there I might have missed it. The 48 hours came and went, nothing heard from Holley. Their 1-800 number is for ordering a catalog only.
Click to expand...
let me confirm the part number and take a look at it tonight.
 

Edbert

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May 16, 2005
#15
  • May 16, 2005
  • #15
Well, I never heard back from Holley, I called and got a machine (did not leave a message), so I removed the pump to look. There WAS a very small "in" written by one of the ports, it was so close to the oil filter that I could not see it with it installed. For the sake of having the answer it is the rear port that connects to the tank and the front port to the carb.

That is the good news. I rotated the lower half one "notch" so that my 90-degree -8AN swivel could clear the oil filter and remounted the pump. More accurately, I tried to remount the pump. This pump is not going to work on my car unless I do a remote oil filter kit. Having the two outlets 180 degrees apart simply does not allow for enough room between the oil filter in the back and the radiator hose in the front. Perhaps it could work with a rubber fuel line but the braided stuff and the AN fittings are just too bulky.

I have a new pump on order, it will have both the inlet and the outlet in the front with 30-45 degrees of separation. Anyone want an unused 110gph mechanical fuel pump that I paid ~$90 for? LOL
 
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