1997 GTX has me baffled

[kwellmancpa]

I have a 1997 GTX with a 787 engine. It started when it ran good idle, but wouldn't take throttle. I pulled the carbs and sure enough, the filters were plugged so I cleaned them. Put back together, and kept stopping like battery was dead, did finally get it to fire, then loud noise and shut it down. Here a hose clamp dropped in rotary valve hole, so had to have the block repaired, and replaced worm gear in rotary valve. So completely reassembled to specs in manual with torque settings, etc. Rotary valve timing set approx. 146.5 and 65 respectively. It seems to want to crank and crank and crank before it will start. When finally started, it only idled around 1500 out of water, and a little rough. If I tried to start again while still warm, would fire right up, when sets overnight, have to crank and crank to get running. I did adjust up idling to be around 3200 out of water. It seems like it may be a fuel priming issue, not sure. Checked compression, I have between 135-140 in each cylinder, rechecked filters in the carbs, changed plugs. I pulled apart petcock tonight and cleaned, but not much to clean, I don't know what else to do. I checked the diaphram on the fuel pump, I hooked up a fuel pressure guage between carbs, and it has about 2 pounds when running, but only about a 1/2 pound when cranking. Is someone able to help?

 

[timmyboy76]

What about installing primer kit, where choke is...has directions on what line/s to tap into...

 

[JPX]

Is the choke adjusted correctly?

New plugs and gapped?

Check hose connections at the fuel baffle. Check valve operating correctly and not clogged?

Fuel selector clean?

 

[kwellmancpa]

Yes, choke is adjusted correctly. Also throttle plates, since there is no holes in them, adjusted where there is a slight opening in them. Also new plugs and gapped correctly. Fuel selector all lines pulled off and cleaned, and hosed at the baffle, if you mean on top of the tank, re tightened all of them. Still baffled, LOL

 

[salmonkiller01]

did you replace the rotary valve itself. My seadoo had similar starting problems and it came down to a worn rotary valve. My valve had some scrapes and pitting.

 

[kwellmancpa]

Did not replace, did scotch brite it while it was out and cleaned it up. When I put back together, checked the clearance and it had .012 between it and the cover, and the manual specs state it should have between .010 and .014, so right dead center in the specs. This thing really has me baffled, not sure if the fuel pump is weak, but if it was, it wouldnt run good once it was started. I am about to put in a primer kit just so I can get to ride it some, then strip it back down and do it again over the winter, well, at least strip it down to assembled crank, and start with another new base gasket and work up. Just really has me puzzled.