[pikachew]

I have what I think is a 1998 XL1200. The title says 1996 but I cant find that Yamaha made a XL1200 in 1996. Anyway, I have a problem. I just acquired this jet ski. it was running a little rough so I thought I would rebuild the carbs. I pulled them off and stated taking them apart just to find that it looks like they had just been rebuilt, new diaphragm, new gaskets. so I decided to put them back together as is and reinstall on ski. I reset high and low jets to what I think is factory settings. but now the ski is hard to start, runs semi decent through low speeds. runs very well at highspeed but only for about 10 seconds. after the ten seconds it bogs down and acts like it is out of fuel and if I keep throttle down it will stall and is very hard to restart (most times I have to use primer ball). if I let off the gas when it is bogging down it will return to idle and bog down if I try to give it gas immediately. if I give it about 5 seconds before giving it throttle

most times it will go through the throttle range great until full throttle again until it starts bogging down again. Any ideas? Anybody know true factory specs on this ski/

 

[Dave in DE]

Pikachew, you can check the year on the HIN tag on the rear Conner of the ski. A BLK tag stamped YAMAHA######## just like your car VIN. the last 2 numbers are the year. 98 would be a 1998, 01 = 2001 and so forth.

When you say "primer ball" do you mean a pump ball like those used on a outboard boat?
If so, this is likely to be most or all of the problem. Those have check valves in them that will starve the ski of fuel. They can not be used on a jet ski and have probably destroyed the fuel pumps in the carbs. I would remove that pump ball and rebuild the cabs again with genuine mykuni carb kits not after market kits.
If the carbs are correct no primer is needed. Just the chokes will do. How ever if you choose to do so the chokes can be removed from carbs and primer kit installed. Find it at SBT, or Riva Racing, or many other jet ski parts suppliers.

Unfortunately I don't have the carb set up for you but if you have a manual you should find base set up in it.
"Rodsatheart" here on this site may have a good starting point for you. He may chime in, if not try contacting him directly. If he doesn't, post back and let me know. I can txt/call him.

 

[pikachew]

I checked the HIN and sure enough it says 96. just weird that I cannot find that Yamaha made an XL1200 in 1996. Yes this ski has a big primer ball and it has the fuel pumps removed from carbs. it does have a external fuel pump. The choke has been already removed an replaced with primer. The ski doesn't have a air box and the primer line is just dangling there not hooked up. thank you for your help.

 

[Dave in DE]

We need to figure out what you have.

Look at the inside of the hull on the left side there should be a sticker with model number. (See pic) the sticker is about 1"x 3". Post the model number then we should be able to get to the bottom of what you have.

 

[pikachew]

Hey Dave. Thanks for helping me out.

 

[pikachew]

Here's a better pic I rubbed a dirty finger on it.

 

[pikachew]

oops

 

[Dave in DE]

Pikachew, no problem, that's what we're here for is to help.
Ok. Now your HIN tag says 96. The model tag xl1200w is 98. And from pics I'd have guessed 98/99. Let's try to ID the motor to make sure it's not a swap out. I won't ask to find model tag on it as it's burried deep under the exhaust. Post a few pics of the motor for me please. Then we can figure what we're working on.

 

[pikachew]

Dave, here are a couple pics. I just replaced the fuel pump thinking maybe it was starving for fuel. it runs horrible now. now it doesn't even have low end power. now im thinking to much fuel pressure. idk This ski is going to drive me crazy. the more I work on it the worse it runs. Thanks again, Dennis

 

[Dave in DE]

Dennis, based on motor tag it's 1200. I don't understand why it has a 96 on hin tag though.
How many hours on ski?
Have you checked the compression on each cyl? If yes what were the results? This is critical on 2 strokes before you make to many changes.

 

[pikachew]

IDK on hours gauge does not work. I purchased a new/used one, says I got 80 hrs! I got this ski from a guy who had a junkyard of skis. I'm guessing this ski is a Frankenstein. I checked compression and got around 95psi on all three cylinders. I'm thinking of purchasing a set of used carbs with fuel pumps and getting rid of the external pump.

 

[Dave in DE]

Frankenski is what I was afaid of with the numbers being what they are. The other thing that doesn't seem right is the motor tag tells me non power-valve 1200 but the carb set up says 1100 to me. That being said it's not unsalvageable just going to need a lot of sorting out if this is the case.
The 95 for compression is low should be around 120/125 but could be the gauge depending on brand. I don't consider myself a good carb guy. I'll contact Rods and see if he can shed some light on things. Surprised he hasn't chimed in by now actually.

 

[pikachew]

Just bought used carbs w/ fuel pumps on eBay. Also got genuine rebuild kit for carbs. going to try to go back to stock setup. i'm going to ditch the primer ball as well. Fingers crossed. I will keep you posted. in the mean time any input you may have will be greatly appreciated.

Dennis

 

[rodsatheart]

The 1100 engine did use a remote fuel pump, but they would have to be rejetted to use on the 1200. Pm or post a picture of the hin. The 1200 settings will not work. Try setting the low speed screws to 1 1/8 +/- 1/4 and the highs to 7/8 +/- 1/4. Those settings are for a wave raider 1100, but might be a good start. Replace the pulse line. It is to short and is kinking. Cap the extra ports correctly with something that will handle fuel or just loop them to each other and zip tie. The return line on #1 carb needs a zip tie. If your going to do th carbs right, you need a mikuni 100psi pop off gauge to check needle pop off. Don't need to change the springs, and poss not the needles either, but you need to make sure they are all close.

 

[rodsatheart]

Your also going to need the 1200 flame arrestor. It needs to be there. Won't run right without it.

 

[pikachew]

you don't think I should replace carbs? Those setting are close to where im set now. im at 1 on high and low. i

 

[pikachew]

i have tried adjusting until I was blue in the face. Doesn't help the way it runs. I have tried to find an arrestor but have been unsuccessful finding on with the 3 bolt configuration these carbs have. i can find 2 bolt and 4 bolt. none have 3

 

[Dave in DE]

I hate to say this but that hin looks like it's been replaced. A lot of damage at the ends around the rivets

 

[pikachew]

When I receive the carbs I will rebuild them. What pop off pressure should I have? and what jets would you recommend?

 

[rodsatheart]

Call Yamaha and see if they can run that hin. Prob. for a 96 wave venture. Need to find the second hin and have it run to make sure it's not stolen, then get the paperwork fixed. Dave, where are yours ? Might pull the front storage and look between the hood bracket and bow. Looks like the main jet should be 135. Pilots should be 1)100, 2)95, 3) 97.5. Low speed screws are 1 & 2 at 1 1/4, 3 at 1 1/8. High speed screws are 1 & 3 at 1/2 and 2 at 7/8. Can't find pop off info. Thinking around 60 with stock needle and spring.
Check and document all current screw and pop offs before disassembling.