Custom/Hybrid Help with DASA 1200

Ski was running perfectly fine until tonight, I rode it for about 10 min, just finished babying it to warm it up, when a boat went by. I hit their wake a couple times getting some decent air, after the third time I jumped it my ski started running like crap. I thought it had possibly ingested some water that was sloshing around inside the hull so I continued to ride for another minute or so, but it didn't clear up. Rode it to shore to investigate and I couldn't see anything wrong. Fired it up on the dock and it started to run away on me, so I instantly grabbed the throttle and hit the kill switch and it died. Pulled the plugs and the mag cylinder looked lean. Up until this point both cylinders were on the rich side, I even used an inspection camera to check piston wash yesterday and my engine builder even confirmed that it was still rich when I sent him the pics. I double checked all my mixture screws and they're all good, I decided to richen them back up some more and try it out. Put it back in the water and it was still running like :):):):), almost like it was running on one cylinder. I grabbed full throttle a couple times and after a couple seconds it would catch and almost rip out of my arms but as soon as I let the rpm's drop down it would run like crap again. At this point I loaded it up and took it home. At home I checked compression and spark and they're fine. I have good fuel flow to the carbs (took off the return lines and turned it over and had lots of fuel coming out). The next thing I guess will be pulling the ebox and making sure all my grounds and everything are still good unless someone has any other suggestions?

I'm running MSD total loss and Full Spec 49's.
 
I had this same problem last weekend, I took it home and completely went through the entire fuel system. Had a piece of plastic stuck in the pump diaphragm on my lean cylinder and a couple gaskets that needed replacing. Back to normal now.
 
I took the carbs apart and found nothing, they look perfect. Reinstalled them and fired it up and it seems a little better but still not running right until it reaches higher rpm. I was running it with the flame arresters off to be able to see the fuel in the carbs. Is fuel supposed to just dribble out of the ring in the throat of the carb (I don't know the name of the ring)
 
Just checked for air leaks by spraying carb cleaner around all the gaskets and I don't have an airleak, just for the hell of it I sprayed some in each carb. When I spray it in the pto side carb it revs up a bit, but when I spray it in the mag side carb it causes the motor to die. I'm confused????
 
Ya it's good and tight. I pulled the flywheel cover and found metal shavings. The pickups were covered in metal shavings too, I think it was maybe throwing off the signal. I had a magnet shred on me a month or so ago and I thought I had removed all the metal shrapnel, but I didn't pull the stator so there must have been a bunch behind it. Now I attempted to pull the stator but I ended up stripping the one stator plate allen head bolt and can't get an EZ out or anything to work so I'll have to pull the motor after the long weekend here and take it to a machine shop and get them to remove that bolt for me.
 

Matt_E

steals hub caps from cars
Site Supporter
Location
at peace
I had similar issues last year. Found some debris in one pilot jet, but the biggest issue was a one-year old plastic fuel filter feeding the PTO carb that had a tiny crack. It would introduce air bubbles into the fuel and make it run horrible. Cold Fusion fuel filters, and BAM!, problem fixed.
 

Big Kahuna

Administrator
Location
Tuscaloosa, AL
Check your fuel lines, if you run translucent lines look for air bubbles. Had this problem a few years ago, we swapped carbs, everything. Then got lucky and spotted the bubbles......... Cut back fuel line and fixed.
 
I had similar issues last year. Found some debris in one pilot jet, but the biggest issue was a one-year old plastic fuel filter feeding the PTO carb that had a tiny crack. It would introduce air bubbles into the fuel and make it run horrible. Cold Fusion fuel filters, and BAM!, problem fixed.


I bet this is what is causing my problems...I had my filters between my fuel tank and water box and they're the plastic ones. I didn't even think about them cracking, good thing I have spares, I'll try this tomorrow. Thanks for your help guys!
 
I only ever run OEM fuel hose now, had the same issues as above with leaks (but at the carb end where you CANT see it)

Pull the motor and walk through it end to end, it shouldn't take long to find the issue.. Have you checked your reeds?

The annular discharge ring in the carbs should vapourise fuel cleanly when you blip the throttle - I have the same carbs, here's mine for comparison:

http://youtu.be/gELgj2RFbFk

Jim
 
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If your dribbling it could be a stuck or worn needle/seat dumping fuel in that can't combust properly until you open the carb throat/it spools up and it pulls enough air to mix with the gobs of fuel?
 
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Hey Chad, If it turns out it's the fuel filter(s) let me know. I'm guessing you're running the same filters in the FRkt as you had in the Matrix I bought from you? The Matrix is running strong, the 865 pulls like a mofo.
KB
 
I finally got everything back together after the debacle I had removing the one stator bolt...ended up having to split the cases to remove it. I took my carbs apart and checked everything in them and they look perfect, checked popoff and both carbs pop at 20 psi. I pressure tested my fuel lines and filters to 20 psi and they held solid, so they're not cracked. I have ran it on the hose with an inline spark tester and both cylinders have good spark. It won't start very well on it's own any more, I dump a little fuel down the carbs to prime it and it starts right up. When I rev it up there's a definite hesitation until it get's about halfway up the revs then it sounds normal. I'm stumped
 

Jp79

Building Brawlers
Location
Harveys Lake,Pa
It dribbles at idle, when I blip the throttle it atomizes the fuel.

Just had the same issue, I had bad needle n seat and the fuel tank vent was bad. Carbs would dribble at idle and be fine once you revved up.
 
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