Fuel pump problem

[ldclarkejr]

I had a problem with my 1996 xp (787). It hesitated when I accelerated, and would cut off if I didn't let off the throttle. Looking back, I think this original problem was the fuel filter in the carb. But, I rebuilt the fuel pump (including the carb filter), replaced the gray fuel lines, put in an in-line fuel filter, cleaned the fuel selector switch. Now it's not pumping gas. I've taken the fuel pump apart several times, but I can't find anything wrong. I put a pump bulb in the fuel line, and it will run if I pump the bulb. I can't thing of anything else to try. Help!! Thanks. Oh, and also, I am getting the engine pulse going into the fuel pump.

 

[kustomkarl]

Welcome to the seadoo forum.You need to add you seadoo model and year to your aviator for future problems or questions. Is the accelerator pump pumping fuel in the carbs? to check it with the engine not running, put you fingers in the throat of the carbs and push the throttle open. You should feel or see, if you use a mirror, the fuel squirt when you apply fuel. thre is a good chance the brass end fittings in the carbs are plugged.

Karl

 

[boatmonkey82]

check your compression , if its low it may not have enough pulse to power the pump . did you put your check valves in the correct side up ? had to see somtimes but the are concave and if put in backwards it wont pump . its a simple problem just keep at it youll get it

 

[ldclarkejr]

Check valves: In the rebuilding kit, they said I needed this special tool that looked like a small metal rod with a rounded end (not included) to install the check valves. I tried to get them in without the tool, and punctured the rubber gromets holding the plastic disks, so I put the original check valves back in, since the problem appeared to be the clogged carb filter. Are they that sensitive so that could be the problem/ Can I buy they check values without buying a complete rebuild kit?
Thanks for your help.

 

[timmyboy76]

o-ring..

bypass the inline filter (factory one) and see what happens. Your synptom is likely caused by the o-ring being bad, inside the filter..(white cannister/water trap, looking thing)

 

[ldclarkejr]

Bypassed the factory filter

Thanks for the suggestion. I bypassed the factory filter and put in an inline automotive filter. I was scared to go without a filter because I think my original problem was caused by a clogged carb filter. One thing I messed up when I rebuilt the fuel pump was to destroy the new check valve rubber grommets, so I put the old check valves back in the pump. Maybe that's keeping it from pumping. I've ordered new ones from a local dealer here in Richmond ($13). Question: The instructions for installing the check valves show using a special tool (not included, of course) that looked like a skinny rod with a rounded end to push the check valves into the housing. I didn't have one and messed the grommets up by trying to improvise. Is there a trick to installing those things, or is that rod necessary. It's a tight fit.
Thanks.

 

[timmyboy76]

alright..possible, you installed the check valves on wrong side..? Verify that the fuel lines are routed correctly to/from fuel slelector to inline filter to carb..?

 

[seadoosnipe]

Automotive fuel filter?

Thanks for the suggestion. I bypassed the factory filter and put in an inline automotive filter. I was scared to go without a filter because I think my original problem was caused by a clogged carb filter. One thing I messed up when I rebuilt the fuel pump was to destroy the new check valve rubber grommets, so I put the old check valves back in the pump. Maybe that's keeping it from pumping. I've ordered new ones from a local dealer here in Richmond ($13). Question: The instructions for installing the check valves show using a special tool (not included, of course) that looked like a skinny rod with a rounded end to push the check valves into the housing. I didn't have one and messed the grommets up by trying to improvise. Is there a trick to installing those things, or is that rod necessary. It's a tight fit.
Thanks.

Do not use an automotive paper filter. The restriction to flow is to great.

Walmart carries a see thru fuel filter with the mesh basket type screens we use inside the carbs. Run by Wallyworld and get one of them. I think it was $9 bucks. They sell replacement filters in packs of 3...........:cheers:

 

[ldclarkejr]

Fuel filter

Thanks, I'll try that.

 

[bradm]

do a pressure test

Did you do a pressure test? I believe you are supposed to pump in 5 PSI and it should hold at 5 PSI for 10 minutes.

 

[ldclarkejr]

Pressure test

Thanks. I'll try that either next weekend or the following weekend. The season is running out. I ordered new check valves, and this will give me a measure of the pressure I should be looking for.

 

[seadoosnipe]

Pressure test...?

Did you do a pressure test? I believe you are supposed to pump in 5 PSI and it should hold at 5 PSI for 10 minutes.

I don't think that applies to this type problem. When re-building your carbs, you connect an air line to the inlet and pinch the outlet. Apply 5 PSI for 10 seconds to see if there is a leak in a gasket.

You may have to go through your system again, make sure you did not put the return line on the supply line etc........make sure you got your check valves installed correctly but I don't think you need to do a pressure test in this situation........:cheers:

 

[seadoobutch787]

I would have bought 2 new rebuild kits for the carbs. They come with new grommets for the check valves. The fuel pump diaphram wear out after awhile from flexing and that will cause your problems.

PS 96xp don't have accel pumps on them.

 

[seadoosnipe]

1997 787cc....

I have an all original 787cc in my 1997 Challenger, including the fuel diaphragms. The only thing I've had to do to the carbs is clean them and fix a bushing on the throttle plate.

Under normal circumstances, your right, there are no accelerator pumps on the 96's..... but you'd be surprised at how many boats or skis I've brought in the past few years that had them. Of course, when asked, 90% said they got them off ebay...........:cheers:

 

[ldclarkejr]

Seadoo fuel pump repair

So, does anyone know the trick to installing new grommets with the check valves? The rebuild kit said to use a special installation tool (not included of course) to push the rubber grommet through the hole in the fuel pump body. It looks like a straightened out paper clip with a tiny ball on the end. I've destroyed the first set of grommets trying to improvise. I've got another kit, but I don't want to destroy this set. Any suggestions?
Thanks.