1810 need help fuel pump

cub149 · #1 07-18-2013, 09:19 PM

I am putting an electric fuel pump on an 1810 and need to know what wire from the igntion I should use. I was thinking the white wire going to the hour meter?
I can't post a picture of the wiring diagram but here is the link to the pdf file. It is on page 110. Thanks for any help.

http://www.onlycubcadets.net/pdf/772-3899.pdf

Oak · #2 07-18-2013, 10:55 PM

That will work and also put a manual shut off after the pump to run the carb out of fuel before you shut it down.

J-Mech · #3 07-19-2013, 12:22 AM

Quote:

Originally Posted by Oak

That will work and also put a manual shut off after the pump to run the carb out of fuel before you shut it down.

I really don't think that is necessary..... the old mechanical pump pumped fuel till the motor stopped turning. This one will die with the key.

Oak · #4 07-19-2013, 12:40 AM

I don't know much about pumps but can they still pass fuel if the float sticks open and on the 82 series the tank is above the carb? I put those cheap little red and black shutoff valves on all my gas machines if the tank is above the carb. Actually, I removed the pump on an 1811 I had and never had a problem with gravity feed.

J-Mech · #5 07-19-2013, 12:49 AM

Quote:

Originally Posted by Oak

I don't know much about pumps but can they still pass fuel if the float sticks open and on the 82 series the tank is above the carb? I put those cheap little red and black shutoff valves on all my gas machines if the tank is above the carb. Actually, I removed the pump on an 1811 I had and never had a problem with gravity feed.

Sure, they can still pass fuel if the float sticks. But, if everything is in good working order, that won't happen. It's no big deal, and I'm not argueing one way or another. But there is already a shut off on the tank.... I never shut mine off. If I have one that starts to leak, I just fix it. I've seen as many problems with dry-bowl carbs that leak because the seals dry out as I have seen floats stick. It's 6 to 1, half a dozen to the other.

inspectorudy · #6 07-19-2013, 09:58 AM

One thing to remember when you switch to an electric pump is when you are doing anything with the key on the pump will be running. If all is well in the carb that will not be an issue. But if as mentioned above the valve is stuck open then you will be flooding the carb and engine. If for some reason you are diagnosing an electrical problem while keeping the key on for a long time you might want to stick a separate switch in the circuit to disarm the fuel pump. In a fuel injected vehicle the electric fuel pump has a return line for the unused fuel and there is no pressure build up on the pump. I do not know what happens on one of our engines if the fuel pump is allowed to run for a long period of time with no pressure relief. Maybe one of our gurus can tell you.

J-Mech · #7 07-19-2013, 11:41 AM

Quote:

Originally Posted by inspectorudy

"you might want to stick a separate switch in the circuit to disarm the fuel pump"

Or just remember to unplug it....... no sense in spending money on an unnecessary switch.

Quote:

Originally Posted by inspectorudy

"In a fuel injected vehicle the electric fuel pump has a return line for the unused fuel and there is no pressure build up on the pump."

This is not true. There is still pressure on the fuel system. But with the motor off, the pump only runs for a set amount of time (about 15-20 sec) and then shuts off. A good fuel system should hold pressure for a few hours. But we are talking about Cub Cadets here, so no matter........

Quote:

Originally Posted by inspectorudy

"I do not know what happens on one of our engines if the fuel pump is allowed to run for a long period of time with no pressure relief."

Nothing. The pump destrokes. Just like it does when the motor is at idle for long periods of time and not using much fuel. That said, it is still a good idea to kill power to it if the key is left on for long periods of time. (10-15 min or longer.) If nothing else it will run the battery dead quicker.

inspectorudy · #8 07-19-2013, 06:25 PM

Maybe you can explain the function of the return line in every fuel injected car I have ever owned? Of course there is a constant pressure in the fuel system but when it is exceeded the return line routes the excess fuel back to the tank. That was the way it was explained to me

J-Mech · #9 07-19-2013, 07:05 PM

Quote:

Originally Posted by inspectorudy

Maybe you can explain the function of the return line in every fuel injected car I have ever owned? Of course there is a constant pressure in the fuel system but when it is exceeded the return line routes the excess fuel back to the tank. That was the way it was explained to me

Yes, SOME cars have a return line. Yes, it returns unused fuel. The fuel pressure regulator is on the end of the injection rail, and it maintains a constant pressure on the fuel rail/injectors. Then, what isn't used, returns to the tank. But, the PUMP, is ALWAYS under pressure when running. Most newer (2000's and above) don't even have a return line. Just a pressure one.

Here is the #1 point. The one added to the cub runs at approx 6PSI, whereas the one on a car is around 60PSI. We are comparing apples and oranges.

cub149 · #10 07-19-2013, 08:51 PM

For what it's worth, my Chevy truck has a return line and I know because I just replaced the fuel pump and sending unit (a job from heck). Back to the original post. I have my pump wired in and ready to go. My next question is: Can I leave the manual pump mounted or should I take it out and make a plate to cover the hole? Or just plug the ends of the pump?