Electric fuel pump

I am thinking of putting an electric fuel pump on my 55. I can get a 1.5-4 psi with 25 gpm or a 5-7 psi with 32 gpm. Which would be the best way to go?

1.5-4 psi is probably a bit low, and 5-7 psi is at the top end.

If you check around, there's some 4-6 psi units available, as well which may be a better choice for an older engine (and carb), IMHO.

I run 1-2 psi on all mine with adjustable fuel pressure regulators on them until I found the lower psi pumps like the 1-4 to speak of,, they do not take much psi or they push past the needle and seat
cnt

As Tom stated the lower pumps do well and
less problems with the carb.Make sure to
fuse the pump and wire the pump so when the
engine is off that the pump is off.Even
with the low pressure pump I still buy and
use the pressure regulator.A dirty or
partly plugged fuel filter will shorten the
fuel pumps life.

I don't know what a "55" is but I assume the tractor has a gravity feed fuel system, i.e. no fuel pump. As such the inlet needle and seat is sized larger to flow fuel at a very low fuel pressure. The larger needle/seat makes the carb more sensitive to fuel pressure level. For gasoline the head pressure, distance of the gasoline level above that of the carb inlet is, 1.7 Psi/Ft of height. Therefore, the maximum pressure available is with a full tank and the minimum occurs once the tank is empty.

The float level specified for your tractor takes into account the level of fuel (buoyancy) the float needs to close the needle against the pressure of the incoming fuel. Increasing the fuel pressure will increase the float level, causing the fuel mixture to move richer. Small increases can be adjusted for, larger cannot and the engine simply runs rich. Increase the pressure further and the fuel pressure over comes the ability of the float to close the needle, resulting in flooding.

I tried an electric pump (I had laying around) on a 16 HP Kohler and experienced the unable to adjust for rich condition. Finally, the "correct" pump I selected was a Facet #60304, 1-2 Psi, 15 GPH. That was in 1917....I recommend the use of "correctly selected" electric pumps.

A JD ?55? is a combine and does use a fuel pump since the
engine is above the gas tank.

(quoted from post at 11:12:21 07/04/19) A JD ?55? is a combine and does use a fuel pump since the
engine is above the gas tank.

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Yes, and that's EXACTLY why I suggested an electrical pump in the 4-6 psi range.

The pump has to LIFT the fuel up to the level of the carb, plus have a few psi left to flow enough through the needle and seat to keep up under load.

The engine originally had a mech fuel pump at the engine, so the carb IS designed to work with fuel pump pressure vs. gravity flow.

There won't be much left of 1-2 psi after it lifts the column of gasoline something like, 5-6 feet from a nearly empty gastank on the side of the combine up to the carb on the engine sitting on top of the combine.

Hate to break it to you but I have done Dozens of them, go ahead install the high psi pump you will find out why I posted what I did, by the way I have 14 combines many have had this done to them, ones I did not use the lower psi pump I had to buy a fuel pressure regulator for not my first rodeo been at this for over 50 years now but what the heck do I know I was just trying to save some problems I always mount the pump at the tank outlet area, as a electric pump will push far more than it will pull but again what do I know, I can say this I am all but done trying to help on this whole site
cnt

My Case 600 uses a 2.5 - 4 psi pump. Haven?t had any
issues yet and it was put on by the previous owner.

(quoted from post at 13:50:33 07/04/19) Hate to break it to you but I have done Dozens of them, go ahead install the high psi pump you will find out why I posted what I did, by the way I have 14 combines many have had this done to them, ones I did not use the lower psi pump I had to buy a fuel pressure regulator for not my first rodeo been at this for over 50 years now but what the heck do I know I was just trying to save some problems I always mount the pump at the tank outlet area, as a electric pump will push far more than it will pull but again what do I know, I can say this I am all but done trying to help on this whole site
cnt

Click to expand...

Oh, gosh, 1660, you come across like I am bashing you.

I, too have been around a fair amount of gas-powered combines with electric fuel pumps, and am unaware of any that used such a low psi pump, nor have I seen any with fuel pressure regulators.

But, of course, personal experiences vary and I am certainly not doubting yours.

We are talking about an electric pump AT THE TANK lifting fuel a number of feet (which means the psi will be a bit less at the carb level than at the pump level).

Yet, the original mechanical pump mounted way up on the engine almost certainly put out more than 1 or 2 psi, more than likely in the 4-7 psi range.

(quoted from post at 09:12:21 07/04/19) A JD ?55? is a combine and does use a fuel pump since the
engine is above the gas tank.

Click to expand...

Greenenvy, Thank you for correcting me. Since the engine originally had a pump go with a real pump not a 1 - 2 Psi as applicable to gravity systems. Dang Nammit Ennaways, I knew better than to make assumptions.

Indiana Ken

(reply to post at 08:48:24 07/01/19)

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Hey Chester
I bought a 5-7 psi and it was to strong
Have a 3-4 on it now and wish it was lower still
Sometimes it over comes the needle and float
Good luck
Dugger

(reply to post at 19:47:39 07/03/19)

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Cnt, do you recommend any particular brand? There are a lot of different ones but I prefer something not made in China.