Anyone tried an electric fuel pump on a GP12R?

[Jonesyfxr]

DI’d you check your fuel line routing?
Did you pull the sender and remove the flapper?
Did you use oetiker clamps on the fuel lines?

[red5]

Where are you located?

Louisville KY

[red5]

DI’d you check your fuel line routing?
Did you pull the sender and remove the flapper?
Did you use oetiker clamps on the fuel lines?

Not sure what I am checking, the routing is stock. No idea about a sender or a flapper.

No idea about those clamps.

[Jonesyfxr]

The factory fuel routing is the feed into the rear carb, then to each carb, then the return out the front carb to the tank. some people have switched the feeds and returns causing issues.

The flapper in question is at the bottom of the fuel tank sending unit. This becomes stuck and can also cause running issues.

There have been issues with trying to run a gutted stock air box.

Testing the carb pop-off is essential for proper fuel delivery and performance.

[red5]

The factory fuel routing is the feed into the rear carb, then to each carb, then the return out the front carb to the tank. some people have switched the feeds and returns causing issues.

I'll check and make sure these have not been reversed. If they were reversed I would not be able to pump fuel into the carbs via the primer. So I'm guessing this isn't it.



the flapper in question is at the bottom of the fuel tank sending unit. This becomes stuck and can also cause running issues.


How can I Check / test this?


There have been issues with trying to run a gutted stock air box.
What kind of issues? Can't do much about this.


Testing the carb pop-off is essential for proper fuel delivery and performance.

Does this require special tools and such? Never been able to test pop off pressure.

[Jonesyfxr]

You can make your own or buy a pop off tester.... look on youtube.

[raiderteen]

Bought this ski not running right. Took it to a buddy that used to build these things. It appears to have an aftermarket pipe (A cheap one like the stinger). Removed the choke and installed a primer. Gutted the air box, no restrictions, no baffles, just the cover, no hose running to the bow. Pretty sure this system has no cat converter. Removed the carbs, cleaned them and then installed a full rebuild kit on all 3 carbs. It didn't run right.

So I took the carbs off and I bought the actual mikuni carb kits. Pulled the carbs apart and left teh metal parts in a sonic bath over night. Installed the mikuni parts and I still have to pump the primer for it to run.

This sucks. I don't know how to set teh pop off pressure. And I don't think that is my problem. I'm not getting fuel unless I hit the primer.

Not sure where to look.

Had a similar issue on an old two stroke 120 HP outboard and I installed an inline fuel pump. Ran GREAT!

Guys I need to figure this out or I won't be able to use this ski for another year. We have one pwc shop in town and he is backed up for 6 months and wants at least a thousand freaking dollars to mess with it. I'm not going to do that. I figure this out here or next week I buy and updated fire extinguisher and run an inline pump. lol

Not getting fuel. Got any ideas what I can check? Please be very specific on how I check. Wish this bastard was diesel.

If you are running a gutted air box then you need to rejet accordingly. A unrestricted air intake will not allow the needles to open when running the very high factory pop off pressure. I would recommend following the osidebill recipe for that ski which includes deleting the accelerator pump, different needle seat, different spring, and rejetting. The aftermarket stinger pipe doesn't really change much of anything. Just makes for easier access to carbs.

Get the inline fuel pump out of your head. It won't work. These are nothing like outboard motor carbs or any other 2 stroke carbs for that matter. You've got a lot of research to be done if you are insistent on performing the work yourself. Everything being discussed here has been hashed out many hundreds of times already on the forum. Google and the search function on this site are your friend.

[butterbean_29512]

When you rebuilt the carbs did you check the needle arm height with a razor blade? Should be level within a couple thousandths with the carb body. If it's low itll starve the carb, too high can cause flooding. Like others have said, you cannot run an electric pump for this setup. Personally, when I do a set of these carbs once my carb is built, I'll test the fuel pump by installing a piece of fuel line, then pulsing the fuel pump pulse line. If the pump will not pump it is readily apparent. If you are using the stock 1.2 needle and seat and the 115gr spring you can check the mikuni table for the pop off. I personally never check pop off, I check my seat, and spring, (all new BTW) and refer to the chart. One other thing you can check, with the exhaust removed you can check the system for leaks by plugging the tank return line and pressurizing the supply line. In a quiet area, with enough pressure you can hear any leaks. A bad leak will cause the carbs not to pull fuel to the engine. Hope that helps you out.

[EricD]

When I put my motor back in it would not start. But Would like yours with fuel put into it. What I found was I had the fuel lines backwards. Just something to make sure is right.