Trying Again - Blaster Still Running Like Crap

retroicon

XX-xx-XX-xx-XX
Hello again all,

I'm staring a new thread here because, being totally honest, people don't read the thing before posting so I'm starting fresh. After 2 pages, no one reads a damn thing... me included.

So here's what up.

4mm Stroke, 1mm Overbore
Dual 46mm Carbs
MSD Enhancer - NEW
JSS Coil - New from JSS
Zero Lightened Flywheel - New from Zero
Stator - Working when last used
Blaster Mod Pipe
RPM Racing Girdled Head - 205 compression in each hole

Before I continue, I want to be as clear as I can. The Carbs are not the issue. The carbs, fuel lines, fuel line routing, etc are NOT the issue. I've rebuilt them numerous times, they're perfectly clean, all passages flow properly on both carbs. I've eliminated carbs as the issue. They're solid.

The engine passes a leakdown test, the fuel lines are brand new, the engine had just undergone a fresh rebuild. New pistons, rings, fresh hone.

The motor fires, and both cylinders are producing spark. It sounds fine at idle when not under load, and will run at idle in the water under load.

When I pull the throttle, I can tell something is off. Acceleration is slow, it kind of feels like what you'd get on an old Waverunner 3 with a 650 in it, if you remember how those feel. Very slow take off, and feels like it's maxing out in the 25-28mph range.

On deceleration from WOT (which is 25-28mph) I can hear a detonation ping multiple times. This only happens on deceleration, not on acceleration.

The pictures I'm attaching were NEW plugs. I went WOT for about 15 seconds, and shut it down and coasted to shore before taking these pictures.

The front cylinder's plug is on the left, and the rear cylinder's plug is on the right. And yes, those are small droplets on the front plug.

At this point I feel like it has to be electronics.

I'm sure I put the stator plate in the right way, and I'm 99% sure I lined up the timing to be stock. (at this point, I can't be 100% sure because it's running so bad)

Any suggestions based that are NOT carbs.

I haven't checked the electronics yet because I haven't had the time. Finally, I'm not a rookie when it comes to this stuff, I'm just not sure on this one since I've never seen anything like it before. It's typically either a go or a no-go on the electronics. I've been riding for over 20 years, and have always been the wrench on my machines.

-G
 

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Well, since your not sure , QUOTE : '' I'm sure I put the stator plate in the right way, and I'm 99% sure I lined up the timing to be stock. (at this point, I can't be 100% sure because it's running so bad)'' You need to recheck the timing because it must be correct to run perfect .... IT is possible to act like this if you made a mistake , and Im speaking from the experience of making this same mistake . after that I would try a ''coil '' Because I have seen them act this way under load . Thats how I would attack the issue if it was mine however Im no ''gu-ru '' then go from there . good luck
 
It would appear that the issue is caused by a component in the electrical box or the stator. That would narrow it down to enhancer, spark coil, or pulser coil or charge coil of stator. Stator coils can be tested with an analog ac meter while cranking engine with starter, might still give you a false positive in the case of the charge coil. If it was mine, I'd start changing parts -easy for me 'cause I'm a parts ho-
Your plugs look good/ typical.
 

JT_Freeride

John Tetenes @Jtetenes
Location
Long Island
Hey not trying to be a pain in the ass but I know you said you are positive it's not the carbs because you went through them and they are clean but that doesn't mean something isn't wrong with them. My buddy had a set of 38s that he rebuilt with all brand new mikuni parts and the carbs were still messed up. If I were you I would swap your carbs with a friends to make sure that you are 100% it's not them. Also same goes for other parts aswell if you don't wanna by new parts. And always do one part at a time.
 
This may sound out of left field here, but have you considered the fuel valve? I can only assume that they are assembled in the same manner as the Kawi valves as I have never had one apart, but if they are, it is possible the o-ring inside has pretty well deteriorated and either allowing added air into the fuel lines, or water, or both. As I am sure you are aware, if water gets into the needle valve area, because it out weighs fuel it can not pass through or easily pass through. That would certainly make a mess of carburetor related fuel delivery.
 
Location
usa
one thing you might do is check for internal water leaks
the front plug looks a little washed out, the rear looks great
loop all waterlines back together with one line having a t fitting
use a automotive vacuum pump and see if you can hold a vacuum on the water jackets
next I would fire it up while still on vacuum and blast the throttle hard a couple of times and see if you drop vacuum
this was the only way i could find hard to find water ingestion/leaks
 

retroicon

XX-xx-XX-xx-XX
In terms of the fuel valve, there isn't one. Each carb has a line coming to it direct from the tank. There is no selector. Direct, non-cut, non-spliced lines to each carb.

On the carbs, yes, I'm positive they're good. Fuel is flowing through each one, I can see it flowing through the lines and filters when it's running, and they've been taken apart, and put back together 4 times now. All mikuni parts, all new. Pop-off is good on both of them. I do have a single 46 I could possibly try if it gets to that.

Thinking about it today, I'm wondering if Dartman could be on to something. Could it be a small waterleak on the front cylinder causing the problem? Could that be the droplets I'm seeing? A small water leak, maybe one of the o-rings on the head has a small cut, or isn't seated quite right? Could that cause the front-cylinder to be mis-firing when under load because it's the only time the motor has water flowing through it?

I think that might be the first thing I check because it's easier to pull the head, than it is to pull the exhaust and flywheel.

I'm thinking stator/flywheel TBH, but they're both fresh, never used, from the suppliers. The coil was from JSS, and the stator from OCD. Both were not used before going into this machine. (I know they were previously used, before being rebuild by each supplier)

I do have a bunch of spare parts lying around that I can give a shot, and that's going to be up next. I have a spare stator, a single 46 carb on a manifold, a spare stock coil, and probably enough other parts to put together 2 more complete systems.

COULD I be on to something with the head? Could it be a small amount of water injestion causing mis-fires on the front cylinder? I have a spare, never used, Riva head with 35cc domes I could throw on. The existing head is an OLD RPM racing head that had plenty of use. If it was slightly warped, or the domes weren't seated right, or the o-rings weren't properly seated, is this a possiblity? Or am I just trying to talk myself out of pulling the pipe, stator cover, and flywheel to check the stator?

-G
 
Have you tried any of the recomendations yet or are you still contemplating what it might be and thinking of more questions ? get started doing something already ! ""Im not trying to be rude '' but you ain't gonna fix it on this keyboard ! Im anxious to hear what it is and hope you get it fixed .
 

retroicon

XX-xx-XX-xx-XX
Have you tried any of the recomendations yet or are you still contemplating what it might be and thinking of more questions ? get started doing something already ! ""Im not trying to be rude '' but you ain't gonna fix it on this keyboard ! Im anxious to hear what it is and hope you get it fixed .

Yes I've tried things so far. I've rebuild the carbs multiple times, and checked the entire fuel system to eliminate that as an issue. Since that wsn't the issue, I'm moving on to the next thing. I just posted this yesterday, and can't just drop everything to start wrenching.

The reason for posting it to ask for opinions on where to go next. I have a feeling it's electrical, but the small droplets of something on the front-plug had me re-thinking it wondering if it could be unburnt fuel, or if it was water.

Before just randomly pulling everything apart, I figured I'd ask to see if anyone had run into something similar before.
 

JMew03

The call me Mew Mew
Location
DFW,TX
It takes 5 minutes to see what the stator looks like. You dont have to replace any gaskets, no new parts to buy (yet). At least you will know that it is set correctly.


Maybe close the spark plug gaps and see what happens.
 
I know you said the coil is considered to be in known good condition but the loss of one cylinder happened to me last summer with the result being the coil. The ski sounded like a Lawnboy on the water lol. Once I replaced the coil the ski ran really well. Sometimes coils can pass resistance tests by the multimeter but when they heat up they tend to break down. I have had a few coils in various other applications be faulty right out of the box. If you do consider a new coil, I would recommend the JetManiac Yamasaki coil. Also one other area I have read about is the type of plugs, a very small detail that gets overlooked is if the plug is a BR8ES, or B8ES. Because the plug caps come with built in resistors having a resistor plug will further inhibit spark performance, so the recommendation is to use a non-resistor plug. I used to wonder why they made resistor plugs in the marine industry and the only reason I was ever told at the time was non-resistor plugs would interfere with radio waves when they fire making cross talk on marine cb radios difficult understand and broken up. Either way though, it never hurts to have a back up coil in your supply...a JetManiac coil is just that much better to have :)
 

Waterdawg Kustomz

RIP NATION
Location
Pac NW
Guarantee its the stator, ignore what it looks like, and tests with meter. Put a good one in and your done. I have seen it a few times over the years. Makes you want to beat your ski with a bat. New stator is the answer.
 

retroicon

XX-xx-XX-xx-XX
It takes 5 minutes to see what the stator looks like. You dont have to replace any gaskets, no new parts to buy (yet). At least you will know that it is set correctly.


Maybe close the spark plug gaps and see what happens.

5 Minutes? Are you crazy? I have a blaster mod pipe on there. I have to remove at least part of the pipe and bracket before I can even get to the stator. After that I have to remove the flywheel. It takes more than 5 minutes just to get all the tools together.

The blaster is also at my lake house, it's not just sitting in the garage.

I'm not trying to delay this, I just think it's better to have a list of things to look at and/or consider, than to just randomly pull crap apart, cross my fingers I found the right thing, get pissed off when that's not it, then go back to the boards and wait 12 hours for responses. Might as well get it all knocked out at once, and who knows... maybe someone will still chime in with "oh yeah, I had those droplets before, it was this".

On the trailer in the garage, it sounds fine. It idles, and it revs up pretty good. For each part I replace I need to put it all back together, and get it in ridable condition, then take it down to the lake, and launch it. It's at least an hour, if more more.

Could I open the ebox, and leave a big mess of wires lying around while I put it in the water? I guess so, but I just don't like doing things that way.

At this point, no one has even addressed the little droplets on the front plug. I'm not sure if it was water, or fuel since it all just smells like combustion on the plugs. Those tiny droplets have to be something, either fuel or water.
 
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I don't think you need to be too concerned about the water droplets. I noticed that they are not only around the plug rim but up the threads and around the gasket. If water was entering the system internally it most likely would not get that high up the plug. Probably the water came from condensing as you removed the plugs or was laying around the plug on the head when you pulled it. It only take one bead to spread quickly like that.
 
Location
usa
5 Minutes? Are you crazy?

At this point, no one has even addressed the little droplets on the front plug.

I'm not sure if it was water, or fuel since it all just smells like combustion on the plugs. Those tiny droplets have to be something, either fuel or water.

i did
told you to get a vacuum pump and hold a vacuum on the water jacket and give the throttle a rip
if you have a internal water leak it will tell you right away

im an oldtimer thats been there WAY long ago...
 
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