787 Not Starting - does level of boat affect gas gravity feed ???

[FixOrRepairDaily]

New engine / carbs checked out OK - got spark - Started boat right up in waiting for baot ramp for 1 min then went to water and boat wouldn't start!!!! I brought homeand put in driveway - keep changing plugs/ using quick start - but boat won't fire up - plugs wet when i take them out. was told that trying to start boat in slightly angled driveway ( bow angled up) floods engine due to gravity feed - scared same happened on boat ramp - is this true on 96 Challenger single 787?

 

[Dr Honda]

Whoever told you that needs slapped.

OK... on some old crusty IO boat... that it's set up poorly... maybe.

BUT...............................


Seadoo uses pressure regulator carbs, with an internal fuel pump. So... you could flip that boat up on it's tail.. or upside down... and your engine wouldn't flood. (think weedeater)

OK... if it won't start on starter fluid... something is wrong. (if you have spark) You will need to pop the carbs, and check to see if the rotary valve is still spinning. Also... check the compression.

 

[FixOrRepairDaily]

When i crank it with no plugs, getting tons of gas shooting out cylinders, compression great - each time i take the plugs out their soaked with premix?????

 

[FixOrRepairDaily]

had this problem, got it started, then started right up every time until i put it in the water now same problem again. Also, when cranking it in water ( salt) yesterday, did it pick salt water into engine, because i can't flush engine since i cannot start it????

 

[Dr Honda]

If it's flooding that fast, and easy... then the needle and seats are just hanging open, and fuel is pumping in. OR... the return on the carbs are plugged.

 

[FixOrRepairDaily]

If the needle and seats are just hanging open, can they be ajusted to stop this???

 

[FixOrRepairDaily]

Tried starting it agian last night, alot of gas getting thrown out exhaust when cranking and plugs keep getting soaked - needle / seat hanging open???

 

[howie099]

You have to replace the needle/seat. The pair is under $20, but since you taking them part you might have to rebuild them if you damage any gaskets. Popoff pressure controls when the needles open by a spring. Like Dr. Honda said I would check the return line also, try to blow air through it or just repalce it.

 

[Dr Honda]

Tried starting it agian last night, alot of gas getting thrown out exhaust when cranking and plugs keep getting soaked - needle / seat hanging open???

If they are leaking that bad... then they probably need replaced. The needle has a rubber tip, and it may be decayed. BUT... before we jump to concussions... we need the carbs off, and opened up.

Who knows... you may find the screw in the arm came out... or the spring has pop'ed out (not common)... or the return is plugged.

Also... if you open the carbs, and find an aftermarket diaphragm... that could be the problem. (They all suck)


I had a similar, but opposite issue. I swore it was electrical, because one cyl wasn't running. But I couldn't find anything, and once I pulled the carbs... I found a screw came out, and was holding the needle closed.

So... let's not assume anything with this one. We know the symptoms... let's investigate.

 

[FixOrRepairDaily]

Where is the return line and where does it go to , the gas tank???

 

[howie099]

The line goes back to the gas tank.