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Discussion Starter #1
I have had this ski for 12 years. The ski had a hesitation issue out of the hole when I bought the ski. I changed the low end jets from the stock 35 to 50 to lean in out. Changing plugs never helped. Initially it solved the problem but it is back again. I have some 45's and the original 35's. Has anyone had the hesitation and bogging down issue out of the hole with this ski. If so, how did you solve it? I did not change the main jets because the top end is awesome. Fun ski without the bog issue. TIA!

:tango_face_smile::15firing:
 

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The cv's have a inherent lean stumble off idle. Going to a 50 pilot jet would have made it richer which is what you need. When is the last time you thoroughly cleaned the carbs and verified pop off ? The trick is telling the difference between a lean stumble and a rich bog. There are also low speed screws that are capped at the factory. If you remove the caps, you can adjust the screws a tad to help also.
 

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Discussion Starter #3
Thanks for the tips. I haven't had them apart in years. Going to pull them and clean them up today. What is popoff? Also which direction on the screws for rich/lean? I was tempted to try the 45’s because I thought it might be a rich bog. Although I’m not sure exactly how to tell the difference. If I feather it a few times they usually get going. The carps might be coming off a few times. What’s you gut feel on rich or lean with the 50’s in? Thanks again!
 

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50 should be richer. Hold the jet up to the light and compare the hole. The 50 is larger. That's as large as I would go. Pop off is around 15-18 I believe. Backing the screws out makes it richer. The pilot screws are to be set for smooth, highest idle. If they're right, and pop off is good, it will start instantly hot or cold, and should fire off easily after sitting a day or two. I'm assuming it still has the choke ?
 

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Discussion Starter #5
The original 35’s has a larger opening than the 45s I have? That’s why I was confused about lean and rich. I’ll check the 50’s to confirm that. As far as starting and idling the ski is awesome. Coming out of hole on low end is the issue. Not sure if it’s lean stumble or rich bog. If I bring ski back to idle most times it clears and goes if that any help.
 

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Discussion Starter #6
I think I found part of my issue if not all today. When I pulled the air cover off I found the rubber air intake tubes dry rotted. Some big pieces even fell into the carb air intake. Where is good place to buy old Kaw parts? I'm going to fix this first and test before messing with jetting. TIA!!
 

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Discussion Starter #9
The 50’s have smaller openings than the stock 35’s. I’m thinking of trying the 45’s. May have gone a little to lean. Must have been a rich bog initially.
 

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Not sure whats going on there. Maybe the 35's were drilled out. The larger the number is supposed to be a larger jet. I've been searching my butt off to find anything that dismisses this for the cdcv's, and cannot find anything. Compare the 45's and 50's.
With the tubes missing and damaged, it changes the pressure in the carb that will change how fuel is pulled (in a nut shell), and the cv's are extremely temperamental to any changes of that sort, hence the reason people say to leave the choke in place.
 

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Discussion Starter #11
I looked again at the 35, 45, and 50's. You are CORRECT the 50's are larger. Very small difference but larger. See pics with 50 on left. I guess I'll stay the same with the 50's and hope the tubes were the problem. Would that be your gut feel? Thanks for all the help! I'll report back in a couple weeks with the results as I have to go back home from my lake place to pay/work for all this fun I'm having!
 

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Discussion Starter #12
Also, I'm not sure what you are talking about with the choke? The choke system has always been in tack and use it only to start the ski. Is there something else it can be used for?
 

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Some people remove the choke to install a primer system. The cv's don't like that, plus it can help diagnose a lean or rich issue. If the 50's are eliminating the inherent lean stumble and not fouling the plugs, I'd keep them. Bad velocity stacks can do the same thing as removing the choke. It can change the pressure in the carb. Are you sure you got all the pieces out ? Might look down the intake and see if any is sitting on or in the reeds.
 

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Discussion Starter #15
Thanks for the specs but I have the service manual. Years ago I put in the 50's and 160's in the mains to decrease the transition. It worked great for years. I hope the new stacks bring it back to life. I will check the reeds as you suggested. Most of the pieces were large so hoping nothing went to the reeds.

I also have a mint 99 Ultra 150 that is real fun and super fast. I'm looking for an oil leak towards the back of the engine. I have determined that it is NOT the cylinder oil hoses. Might be the back bearing oil hose. It is connected but I still have oil from below the back of the engine somewhere. I am going to replace all the hoses and hope it fixes the leak. Have you heard of oil leaking outside the back bearing oil input?
 

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If it worked good for a extended period with that jetting, and not fouling plugs, I'd put it back. The common denominator seams to be the stacks.
The lines can leak if they have substantial years on them. They can lose their seal, come off, or break. There is a chance it could be leaking from between the case halves I guess. How bad is it leaking ?
 

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Discussion Starter #17
A substantial puddle in the bottom, but only after an extended period. I'm going to change all the lines and see if the problem still exists. Do you know the od and id of the lines? I assume gas type lines from an auto store would be sufficient? Are the bearing lines bigger than the carb lines? Or do my eyes deceive me? Would 20' be enough to do all 5?
TIA!
 

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The carb lines should be 1/8"id. I can't remember on the bearing lines, but I believe they are slightly larger. I just use tygon or other small engine fuel line. Just snip a 1/2" off and take it with you. I'm thinking 8' is enough the do the carbs, but 10 gives room for error. Be sure and keep the lines in order for the carbs. They are specific on the 1200's. You can use high quality 4" zip ties to secure them
 

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Discussion Starter #19
Thanks for the ID size and tygon material. The ski is 90 miles away so I will just take a chance on the 1/8". I have the Ultra manual so I'll see if they are mention in there. I know about keeping the order off the oil pump. The lines are old and need to be changed. They are not brittle but aged. Thanks!
 

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Looks like they're all 1/8". I just added up all the lengths from the parts page and it cam to 8.8ft, so maybe 15ft to allow for error. They're all 3mm id x 6mm od. Your going to have to premix some fuel to idle in the water on until the lines get purged. Normally I like to prefill oil lines with a 50cc syringe after I get them positioned, plug one end with finger, remove syringe, and attach it to pump. Still might get a air bubble or two, but it's better piece of mind for the few minutes of idling while purging. Couldn't hurt to bleed the pump for a min after attaching the lines to make sure no air got in there somehow also.
Again, don't get the lines mixed up. They don't all have the same flow rate.
 
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