97 challenger hard to start and wake surfing question

[rbh]

Hello the 787 in my challenger is awfully hard to start if left overnight or even for like 5 - 6 hours. I have to prime the engine by putting gas directly into the cylinders via sparkplug holes. One little shot and away she goes, will start easily all day as long as you start it ever hour or so. The fuel system has a priming ball which seems to deliver fuel into the bottom of the carbs (totally different llne then the fuel supply). Ive pumped this till my hand cramps up and it still wont start unless i put fuel right into the cylinders... wtf? Im wondering if maybe a guy moved the priming ball on the fuel primary delivery lines? Also, ive read that it should prime by pushing the throttle ahead a couple times... this doesnt seem to do anything on min, cant hear fuel being sprayed or pumped.

Another question, has anyone ever put a wake surfing gate on their ol sea doo jet boat? I dont see why it wouldnt work.. something like this: http://www.themalibucrew.com/index.php?/forums/topic/44826-manual-home-made-surf-gate-teak-gate/

thanks for reading

 

[Andy4k6]

Not sure on the 787 engine but if it's anything like the smaller engined I would be looking at the fuel pump and pulse line.

 

[snikwad003]

The fuel supply does go in the bottom of the carbs. The lines that come out the top of the carbs return unused fuel to the tank. The fuel pump is in the bottom of the carb, and there is line that goes from the crank case to a fitting on the bottom of the carb that pulses the fuel pump and makes it pump

 

[rbh]

The fuel supply does go in the bottom of the carbs. The lines that come out the top of the carbs return unused fuel to the tank. The fuel pump is in the bottom of the carb, and there is line that goes from the crank case to a fitting on the bottom of the carb that pulses the fuel pump and makes it pump

Thanks! that makes way more sense now! Is the only priming procedure to squeeze the ball or do you have to do something with teh throttle too?

 

[snikwad003]

The primer has been added at some point. I would rebuild tour carbs and ditch the primer. The fuel pump in the carbs is pretty stout and should prime its self in 5-10 seconds of cranking. I have not had my boat out since carb rebuild to see if it needs throttle to start up so I dont know there. But on the trailer it starts pumping fuel as soon as I hit the starter. But you loosing prime tells me you are leaking air into the system somewhere or have some bad diaphrams in the carbs.

 

[rbh]

The primer has been added at some point. I would rebuild tour carbs and ditch the primer. The fuel pump in the carbs is pretty stout and should prime its self in 5-10 seconds of cranking. I have not had my boat out since carb rebuild to see if it needs throttle to start up so I dont know there. But on the trailer it starts pumping fuel as soon as I hit the starter. But you loosing prime tells me you are leaking air into the system somewhere or have some bad diaphrams in the carbs.

ah ok thanks! is the fuel pump built into each carb? and its activated from the crank case vacuum? I dont think its diaphrams since it starts right up after its warm and runs great. I read about a guy who was having similar issues and he changed his ground cable from battery and the engine turns over way faster which enabled it to prime... thinking about trying a similar fix before i rebuild the carbs.

 

[snikwad003]

The fuel pump is on the mag carb and yes it is vaccum powered. I ment to say check valves not diaphrams. And any bad/kinda bad electrical connection will bute you in the ass eventually.

 

[howie099]

primer system is just for removing the choke. You need to splice in to a gas feed line and the gas gets squirted in to the top of the carbs. Most seadoo's don't have the hard start issue that you need a primer system. I have it on my Yamaha GP1200 but on one my 3 seadoos.