753 injector pre-pump

[wings5j]

Hi to all,
yesterday I had the chance to help a friend out and did some work on a 753. It has the Kubota V2203-E engine. It would start right up and then die as if running out of fuel. We noticed that someone had installed a marine type pump bulb in the fuel line between the filter and the pre-pump. If one of us stayed at the back and squeezed the bulb, we could keep it running.
We wanted to get it up to the shop to work on and so we tried installing an electric fuel pump in line in place of the priming bulb. This wasn't quite enough help. We pulled the pre-pump and it did not seem to move much fuel when moving the plunger by hand. Then we by-passed everything and put our electric fuel pump in line from the tank and direct to the injector pump. Now it started and ran normal and we move it up to the shop.
Question: Is it best to try and get that pre-pump from Bobcat, a Kubota dealer, or someone else? Any thoughts or suggestions are appreciated. Thanks,
John

 

[mrdeere1959]

where you still going through the fuel filter before you "by-passed" everything. hook a gauge to the lift pump and it should have 5psi or so. also make sure the bleeder is closed on the injector pump

 

[Tazza]

where you still going through the fuel filter before you "by-passed" everything. hook a gauge to the lift pump and it should have 5psi or so. also make sure the bleeder is closed on the injector pump

The bleed screw is the most common area that people over look. You change a filter and prime the engine but forget to close it.
The lift pump should be cheaper at a kubota dealer or ebay if its found to be the problem.
The hand primer is factory.

 

[wings5j]

The bleed screw is the most common area that people over look. You change a filter and prime the engine but forget to close it.
The lift pump should be cheaper at a kubota dealer or ebay if its found to be the problem.
The hand primer is factory.

Thanks guys,
Yes, we checked that the bleed screw was closed. A new filter and lift pump came in the mail yesterday at my friends place. We are headed up to work on the machine today.
I will be working on the lever arm sytem as it has a broken pintle on the left side, needs some pivot bushings, etc.
Good to know about the primer bulb as it sure looked like an ad on by somebody else.
I will try to update on this tomorrow as I should have more info.
John

 

[wings5j]

Thanks guys,
Yes, we checked that the bleed screw was closed. A new filter and lift pump came in the mail yesterday at my friends place. We are headed up to work on the machine today.
I will be working on the lever arm sytem as it has a broken pintle on the left side, needs some pivot bushings, etc.
Good to know about the primer bulb as it sure looked like an ad on by somebody else.
I will try to update on this tomorrow as I should have more info.
John

Well, my friend installed the lift pump and new filter and kept the primer bulb in the system. Seems like we are back in business with a good running engine.
On the other end of things, I replaced the left side pintle arm, a couple of torsion bushings, and adjusted the steering levers and made the neutral adjustment. Still a few things to get done but it was nice to make some progress.
Thanks again,
John

 

[Tazza]

Well, my friend installed the lift pump and new filter and kept the primer bulb in the system. Seems like we are back in business with a good running engine.
On the other end of things, I replaced the left side pintle arm, a couple of torsion bushings, and adjusted the steering levers and made the neutral adjustment. Still a few things to get done but it was nice to make some progress.
Thanks again,
John

Good news indeed, its even better when you can do it all your self and save a few $ and learn more about the machine whle doing it.

 

[7LBSSMALLIE]

Good news indeed, its even better when you can do it all your self and save a few $ and learn more about the machine whle doing it.

has anbody ever figured out why some 2203<s will run with bleeder open and some wont .never been able to put my finger on it

 

[7LBSSMALLIE]

has anbody ever figured out why some 2203<s will run with bleeder open and some wont .never been able to put my finger on it

the rest didnt take. why will some run with bleeder oppen and some wont.

 

[Tazza]

the rest didnt take. why will some run with bleeder oppen and some wont.

I wonder if it has to do with possible restrictions in the return line back to the tank. If its small enough, it still have enough back pressure to keep the injector pump happy?

 

[wings5j]

I wonder if it has to do with possible restrictions in the return line back to the tank. If its small enough, it still have enough back pressure to keep the injector pump happy?

Headed back up to the Bible Camp tomorrow to do some more work on their “new” 753. It will soon have a new shut-off solenoid (they were using a rope and string combo ;-) and a new ignition switch.
We opened up the chain case as the oil in it looked very milky. Cleaned that all out and will put fresh oil in tomorrow. What are the typical ways that water can get into the chain case? Could someone have held the pressure washer over the case vent or something like that?
New friction washers in the throttle lever will now replace the bungee cord they were using too ;-).
They didn't have the back-up horn option on this one but we are thinking of putting one on it because it working around the kids at camp. Does anyone know if this is available as a kit? Any other advice on the back-up horn system will be appreciated.
John

 

[mrdeere1959]

Headed back up to the Bible Camp tomorrow to do some more work on their “new” 753. It will soon have a new shut-off solenoid (they were using a rope and string combo ;-) and a new ignition switch.
We opened up the chain case as the oil in it looked very milky. Cleaned that all out and will put fresh oil in tomorrow. What are the typical ways that water can get into the chain case? Could someone have held the pressure washer over the case vent or something like that?
New friction washers in the throttle lever will now replace the bungee cord they were using too ;-).
They didn't have the back-up horn option on this one but we are thinking of putting one on it because it working around the kids at camp. Does anyone know if this is available as a kit? Any other advice on the back-up horn system will be appreciated.
John

6704442 $166.79

 

[Tazza]

6704442 $166.79

water gets in the chainc ase from bad gaskets on the inspection covers or through the bolt holes or breether. Its meant to be changed every 1000 hours.

 

[woodeneye25]

hi i have a 763 with the same problem ,i found it would only run on a full tank ,so i mounted another tank on the back above the rear bonnet and that works although the bottom tank gets the return line and fills up i cant find a bleed valve i am pondering fix the old pump or put an electric one in

 

[jerry]

hi i have a 763 with the same problem ,i found it would only run on a full tank ,so i mounted another tank on the back above the rear bonnet and that works although the bottom tank gets the return line and fills up i cant find a bleed valve i am pondering fix the old pump or put an electric one in

Woodeneye, sounds like the pickup tube in yours is broken off, search this forum for pickup tube , it is a common problem. I remember a joke from a long time ago involving a woodeneye but can't remember the punch line.

 

[wings5j]

Woodeneye, sounds like the pickup tube in yours is broken off, search this forum for pickup tube , it is a common problem. I remember a joke from a long time ago involving a woodeneye but can't remember the punch line.

Thanks MrDeere for the tip on the alarm kit. Tazza, thanks for the thoughts on the water entry.
Today we put 8 gallons of fresh oil back in the chaincase. I also finished the shut-off solenoid installation; installed a new ignition switch; two new fuse holders; and put all of the steering components back together. It should be ready for a test run soon but have to track down a few more things and not sure how soon I can get back at it.
Thanks again for the help,
John