holley electric fuel pump issue

[sclemons]

I've been doing miscellaneous stuff to my boat over this winter, one of which has been replacing loose electrical connections and re-doping fuel line fittings.
I went to run the motor a bit yesterday and the fuel pump did not want to work right. It use to hum constantly and provide just under 7 lbs pressure. yesterday it would gurgle for a short while then shut off, if I tapped it it would run again for a few seconds then shut off again. I do have fuel in the tank
my questions, before messing with wires,
Do these pumps require priming ? How to prime?
Does this sound like electrical issue? (i doubt it)
Do these pumps just die or do they usually peter out slowly?

 

[merc245]

I got about ten yrs out of my 1st holly red fuel pump. If you had it a while or any time time at all, For a $125.00 I would change it out Its cheap insurance.
After the holly red I went with a cheap knock off and only got about 4 yrs before it went south. So I back with a holly. Change it out. my2$

 

[Big Red]

I've been doing miscellaneous stuff to my boat over this winter, one of which has been replacing loose electrical connections and re-doping fuel line fittings.
I went to run the motor a bit yesterday and the fuel pump did not want to work right. It use to hum constantly and provide just under 7 lbs pressure. yesterday it would gurgle for a short while then shut off, if I tapped it it would run again for a few seconds then shut off again. I do have fuel in the tank
my questions, before messing with wires,
Do these pumps require priming ? How to prime?
Does this sound like electrical issue? (i doubt it)
Do these pumps just die or do they usually peter out slowly?

You can buy a rebuild kit for the pump. What most people dont understand is a Holley pump is a pusher not a puller. The pump is suppose to be mounted below the fuel level. The pump has very little vacuum to full fuel to it. I have not had any problems mounting them at tank level but thats is still not the correct way.

 

[sclemons]

I talked to a friend today about this issue.
he has two boats that each have two electric fuel pumps and he has often had to disassemble them and clean the brushes and contacts, I will try that tommorrow and post my results. with it working by tapping on it that sounds like a logical source of the problem. paying 125.00 for a new one is not a big deal, but if i can fix it for 1/2 hour of my time that is what i will try first.
Red, the only way I can possibly mount this below my fuel tank is to put it in the bilge area below the engine, I don't see that as being a good idea. I don't even see how any car, boat or truck can mount this below the fuel source. You may be correct but it just doesn't make sense, but I still appreciate your imput.

 

[Big Red]

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PUMP MOUNTING AND INSTALLATION: HOLLEY FUEL PUMPS​

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The best location for mounting any electric fuel pump is the rear of the vehicle. The inlet and outlet of the pump must be
mounted below the lowest point of the tank. This is necessary to allow for an adequate fuel supply. The pump is designed to
push fuel and not designed to suck fuel out of the tank. It needs to be gravity-fed or if it’s pulling from the top of the tank, it
needs to develop a siphon feed to the pump. The pump should be mounted on the chassis, in a vertical position with the pump
motor on top. Avoid exposure of the pump and fuel lines to moving parts and to any hot areas, such as the exhaust manifold.​

The pump should not be mounted in a closed area, such as the vehicle’s trunk. Follow the steps below for mounting the pump.

 

[sclemons]

[FONT=Arial,Bold]

PUMP MOUNTING AND INSTALLATION: HOLLEY FUEL PUMPS​

[/FONT]

The best location for mounting any electric fuel pump is the rear of the vehicle. The inlet and outlet of the pump must be
mounted below the lowest point of the tank. This is necessary to allow for an adequate fuel supply. The pump is designed to
push fuel and not designed to suck fuel out of the tank. It needs to be gravity-fed or if it’s pulling from the top of the tank, it
needs to develop a siphon feed to the pump. The pump should be mounted on the chassis, in a vertical position with the pump
motor on top. Avoid exposure of the pump and fuel lines to moving parts and to any hot areas, such as the exhaust manifold.​

The pump should not be mounted in a closed area, such as the vehicle’s trunk. Follow the steps below for mounting the pump.

I appreciate your input Red. This pump has worked reliably in its present location until now, so I doubt it is a location issue. (it is mounted about level with the top of the tank with no more than 2 feet of hose running to it)

 

[mkhammer]

Sounds like that pump is done, They can burn up if they cavatate, This is a problem with a lot of electric fuel pumps that can't siphon if they are mounted above the tank level.
They do need to be primed and that will help. I use the Areomotive M1000 pumps they will siphon up a tree but expensive and must for large engines. I try to use a mechanical pump in most carb engine application when ever possible the 500hp had a mechanical pump on the sea water pump.
If you put a check valve before the pump you can use an outboard primer bulb in between the tank and the pump to prime it. Then get rid of the primer bulb and put you line back on. You can use hose and a double barb fitting from your supply line to put the primer bulb in between temporally. I would not try to rebuild one for the reason if it fails you are stuck. Replace it as mentioned cheap insurance. If it sits for any period of time I don't mean the same day or weekend. I would prime the system again before trying to start it.

 

[sclemons]

thanks MK. my boat has both the mechanical pump and the electric pump.
Would the electric pump even be needed on my motor? it's a 454 w/ 177 blower and dominator 1050 carb (5 - 6 lbs boost)

 

[boatman4021]

Red is correct. Did you ever notice the street rods with an electric pump hanging from under the rear bumper! Or on a race car, they are below the fuel cell? Your pump may have worked the way you have it mounted, but it's not working now. If the pump is pushing fuel faster than it is being supplied, it will not last as long as a pump that is staying "wet" all the time. My opinion, you do need the extra fuel pump. I don't remember exact numbers, but a high perf/race motor should have a fuel delivery system that is capable of filling a 1 gal. gas can in 30 seconds or less. My 10 sec. drag car was loosing power in high gear, did the fuel test. 45 seconds to pump 1 gal with 1 blue holley pump and 1/2" line. The cure, 2 blue holley's, 2 1/2" lines , and 2 reg's. Result, 1 gal in 22 seconds. dropped 3 tenths off 1/8 mile time (6.07) and over 4 from 1/4 mile time(10.27). And this was with a single 1050 dominator.

 

[mkhammer]

thanks MK. my boat has both the mechanical pump and the electric pump.
Would the electric pump even be needed on my motor? it's a 454 w/ 177 blower and dominator 1050 carb (5 - 6 lbs boost)

Ok so your feeding your electric pump with your mechanical pump right?

If so you may not have a siphon problem, but if your mechanical pump got weak and can not keep up it would put a strain on your electric pump and it could fail.
No I would not run a Manual pump only, I was referring to a non supercharged application.

I did not know you had a supercharger and a 1050. If you posted it i did not see it.
For what you have i would get rid of it all and install an aeromotive M1000 pump. It will siphon and keep up with your system always. I would run a boost reference/ bypass regulator with a return line to your tank. You could dial it in at 8 psi and your fuel pressure always be there no matter what the demand. You would have to run a 100 micron filter before the pump and the fuel water separator after. Also a oil pressure fuel switch to turn your pump off when the engine stops.
I know this system is expensive and could set you back $500 or so. but in my opinion for what you have it's the right way to do it.

Or if you replace the system you have buy a high volume high performance mechanical pump.

Procharger feeds their low boost carb kits like that but when you get to a certain level of boost and HP the M1000 is the next move.

You may be border line to needing the upgraded system.

 

[boatman4021]

This is great advice! MK knows what he is talking about. You can buy the best hard parts available, pistons, rods, crank, cam, etc, but the 3 liquids that enter your motor will kill it if you don't have enough! Water, fuel, oil!

 

[sclemons]

thanks for the info MK and Boatman
I am attaching my dyno sheets, please let me know if what you suggest
is still the way to go after reviewing these of if somethig different should
be done
thanks again

 

[sclemons]

took a look at what I have and I am now really scratching my head.
never had a reason to look before. all was working fine.
I have a Holley red and the stock mechanical both going into a manifold, there is a K+N in line filter prior to the Holley electric and a fuel/water seperator prior to the mechanical, from the manifold I have one line going to the primary and one line going to the secondary.
(I should mention that the guy I bought this boat from "claimed" to be an engine builder for GM, no wonder they needed help)
MK, can you provide me with a schematic showing me how to properly fuel this engine?
When/If we ever meet I will provide you with a case of beer, a bottle of scotch, or a magnum of water, your choice.

 

[mkhammer]

I will doodle something up for you. That sounds like a strange setup.
your dyno sheet would not reflect any useful info for this purpose.
from what you have described I would use an Aeromotive pump. This would eliminate excess plumbing and make your system more reliable.

 

[mkhammer]

So do you have a boost refferance carb/ blower carb if not you will have to modify your dominator or send it to a carb shop. basically it needs the vacum port off the metering block.
if not you will have to modify yours.
How about a picture of your setup you can pm it if you want.

 

[sclemons]

I'll try to put something together and send it to you
the carb has no vaccum set-up.
It has an adapter plate between the carb and blower, could a vaccum line be installed there?

 

[mkhammer]

Well I guess I should ask if you are running a power valve or is your dominator power valve blocked and you are just jetted up 12 to 16 sizes.
You don't have to boost refferance your 1050 carb but I like it so it keeps it running clean on the lower end and cruising under boost. The only problem is when you don't boost refferance your power valve, The power valve can shut and lean out when you back off the throttle and can detonate for a short time until it opens again. On a low boost system and a 1050 with a 10.5 PV you may be able to get away with a power valve and no boost refferance line but I would do it if it was mine.
It is not a hard to do modification and Holley can tell you how to do it. or if uncomfortable with trying it send it to a carb shop. Most will charge $300 for 20 min. of work is all it takes.
The boost refferance line has to come from below the blower rotors from the manifold.

I think you need a steady gas flow from a good fuel system/ pump. then the carb is pretty easy to figure out.

 

[Big Red]

Post pics of this, would be intresting to see how that was set up

 

[mkhammer]

Here is how I would plumb your fuel system. BBC 177 blower 1050 domionator.

1/2" line to your fuel /water separator, out the water separator to a in line 100 micron filter, into the M1000 pump. out the pump to an areomotive carb 4-port bypass regulator.
From 1- port 1/2" line to your carb, 2-port liquid filled fuel pressure gauge, 3- port fuel pressure sender for a dash gauge. 4- port plug. return port from regulator 3/8" line back to the fuel tank.
Set your regulator for 8 psi and it will stay there.
Boost reference you power valve on your carb. use a 10.5 power valve.
I use the DOT brake line with reusable fittings. it's the black braided stuff and is fuel rated.
you can get this stuff at a hose supply house that makes hydraulic lines.
I would use a larger than stock fuel/water separator.
You do not need a boost reference regulator on you draw through system.
I would recommend a pyrometer, jet to 1200 deg. WOT. When your back of the throttle
The pyrometer reading should drop with it. if not put in the next size jets in your secondaries until it does.
This is a boat setup It is simple and when dialed in work great.

 

[sclemons]

Thanks MK
I haven't been able to get pics worth sending but what you explained above is well understood.
Red, it is likely you will see me the weekend of June 4,5 when I meet you I'll explain what the set-up was, if I remember.