Crank But no Start! 1998 SPX

[andyman97]

Hi all,
I'm a newbie to jetskis in general, I've been trying real hard the past few days to get my roommate's old 98 SPX started now that the weather's been so nice! I'm somewhat mechanically inclined but never worked on a two stroke before. Here's the problem:
The motor will turn over (brand new battery), but will not fire. I've tried everything I can think of:
Siphoned out old gas, blew out gas lines, filled to top with premium, changed fuel filter, new plugs and checked by grounding on head, removed and cleaned carb, cleaned carb fuel filters (were dirty but not clogged). When I pour a teaspoon of gas in the plugholes or the carb directly it will immediately fire for a second then die. I tried starting it by pulling the gas feed line to the carb and feeding fuel from a can but still no go. I daresay I'm stumped! I know I still have those crappy grey gas lines, but i've blown them all out with air and ran gas thru them with a hand pump and they flow fine. I'll get around to replacing them eventually, but I'd really like to get it to run before going and dumping money on it

(just realized I posted in the wrong section)
Thanks a lot for the feedback,
Andy

 

[Hefty14]

Have a 96 Speedster that did the same thing... If I put fuel in plug holes it would fire up til it burnt the fuel up n then die. My problem was rotary valve gear. Take off the carbs n look back in holes... Manually turn the flywheel and see if the ports are opening n closing as the valve turns. Or u can take off oil pump where n see if there is a bunch of slack in the rotary shaft. If there is or u can turn the shaft by hand then gear is slipping and stripped. If that's the problem, don't just buy the rotary valve gear for $35, but the whole rotary valve shaft cause a lot of times it slightly warps it. If ur lucky u can pull shaft out n stick in a new one. I had to disassemble lower part of block which is probably better. Let's u clean out all the brass shavings. Also make sure to clean out oil lines cause shavings were in there too. If u break open block check the gear in the crank too, mine had slid to one side

 

[andyman97]

Thanks for the reply! Shoot. Sounds complicated... I'll take a look tomorrow evening. Is that something that could just go bad? According to my roomate, it worked fine when he last ran it about 3 years ago and has just been sitting.

 

[Hefty14]

Search "SBT change rotary valve gear" in Google. It's a great video. The whole shaft from there is like $79 and u can get the timing wheel for $10. Once u put the shaft in u will have to set rotary valve timing. I had to pull whole motor out of boat. It sounds intimidating, but honestly I could probly pull motor, replace, set timing in under 2 hours. I think in a ski u can do it without pulling motor in like 30 minutes. Hopefully a veteran will chime n shortly

 

[Hefty14]

https://m.youtube.com/watch?v=ULL5gfQs_UA

Don't get intimidated it's not that bad. I thought it was until I did it

 

[andyman97]

Alright, will do. That does kinda sound intimidating... I don't really have anything to lose so I might give it a shot tomorrow. I'll take a look at the video

 

[Coastiejoe]

Andyman97. I deleted your other identical post. Please do not do duplicate posts, it makes it hard for others to follow and or help you.

 

[andyman97]

Coastiejoe, sorry about that! I intended to put it in the right category and then delete this one, but I already got a reply lll be more careful next time

 

[Coastiejoe]

No issues, I just saw it was identical. If you ever need/want a post moved to a different forum, just ask, we can move them around.

 

[racerxxx]

As hefty said, but you can do it without puking the carbs. Just pull the choke cable out and trust it to the right, it will hold position. Then pull the plug wires and put them on the grounding posts on the rear ebox where the battery cables go into. The posts are right next to the front of the battery. Then cable tie out take the throttle wide open. With a mirror and flash light look thru the carbs, you should see the valve close and open add someone holds the start button down.

 

[andyman97]

Sweet thanks! I'll give it a shot this morning

 

[andyman97]

Hi everyone, finally got it sorted out this morning! I tried the mirror and light thing to look at the rotary valve and it seemed alright. For the life of me I couldn't figure out what the deal was until I tried bypassing the fuel selector knob and it fired! Probably should have checked that when I did all the lines and carb... Oh well. Thanks for all the help I really appreciate it!