Stock Carb 94 750SX

[Magyar68]

Ok so jetting is still an issue with this? In your 3rd Picture the 2 carbs have 4 bolts each. Choose one of them take out the 4 Bolts, the Cover and a Diaphragm will come off, exposing the Fuel block. there will be either 2 or 3 Brass Jets(they look like inserts) 1 at a time remove and take note of the Stamping on the Side of the head of each, and replace. Post up your findings. You may have to play around with it a bit, you have 11005-3720 Cylender which used a weird Bore. I have a 93 witch uses the same part number, so yours should jet closet to mine. Let us know..

 

[bigmike585]

Ok, so I pulled the cover off the carbs and inspected the diaphrams (for tears?) and the needles wear. No visible tears in diaphrams, although I'm not really sure what a perfect diaphram should look like. As for the needles, they appeared normal (no plateaus).

Anyhow, below are some pics of em.

 

[Magyar68]

Ok looks like they only have 2 jets each so CDK duels. this is what was put on the 95 Model. the jets are visible in the last pic. Pull the larger one (High Jet) and a number will be stamped on the side of the head. same with the Small one (low Jet). that 3rd hole is it threaded as well, or is it plugged?

 

[bigmike585]

Ok so jetting is still an issue with this? In your 3rd Picture the 2 carbs have 4 bolts each. Choose one of them take out the 4 Bolts, the Cover and a Diaphragm will come off, exposing the Fuel block. there will be either 2 or 3 Brass Jets(they look like inserts) 1 at a time remove and take note of the Stamping on the Side of the head of each, and replace. Post up your findings. You may have to play around with it a bit, you have 11005-3720 Cylender which used a weird Bore. I have a 93 witch uses the same part number, so yours should jet closet to mine. Let us know..

I havent unscrewed the jets yet, but I already had these pics so I thought I'd throw em up you y'all to check out before I go any further. Sorry the photoshop/paint job is pretty crappy but just wanted to verify a few things. Also, not sure if you can tell anything on the state of the diaphrams judging from the pics, but is there anything else to look for here? Any other wear/tear signs to look for.

Also, I was just going to grab some carb cleaner and start spraying the unit out. Any tips on getting the carbs cleaned up?

 

[bigmike585]

 

[Magyar68]

Yup thats it.

 

[bigmike585]

OK high jet is 115 and low is 75.

No other threaded holes.

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[bigmike585]

Any other things that should be checked, cleaned, maintained, etc on this ski? Any and all advice is appreciated.

Looks like I'm gonna have to replace the battery. Any recommendations on batteries?

I'll need to drain the gas and tank also. Looks like to remove it I'll have to remove part of the exhaust? Was thinking maybe I could just use a siphon. Maybe an air compressor to blow the lines out.

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[Magyar68]

That is the Correct jetting for a stock Engine, so you may need to check the Bore. Does it have old gas, and that why you are going to remove the Tank? If so old gas will cause the Condition you describe in your original post. You will still need to adjust for the altitude, but should be turns on the adjusters and hopefully not new jets. I had to get rid of some old gas, I siphoned it out through the pickup hole in the Tank. then zip-tied a towel to a stick to mop and clean out the rest. Hocking up the Front fuel fill during tank installation\removal is a pain.

 

[bigmike585]

That is the Correct jetting for a stock Engine, so you may need to check the Bore. Does it have old gas, and that why you are going to remove the Tank? If so old gas will cause the Condition you describe in your original post. You will still need to adjust for the altitude, but should be turns on the adjusters and hopefully not new jets. I had to get rid of some old gas, I siphoned it out through the pickup hole in the Tank. then zip-tied a towel to a stick to mop and clean out the rest. Hocking up the Front fuel fill during tank installation\removal is a pain.

last summer when I ran it it was fresh, but I just thought since its been sitting for a year (with no fuel stabilizer) I oughta empty it and start fresh. I really think all I need to do is clean out the carbs and start over on the adjustments (1full turn for each?) and give it a try.



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[bigmike585]

Cleaned the carb and put it back together. Trying to drain the gas tank but siphoning wouldn't work BC the ski is sitting ground level, so I think I may try to pump it out.

Question on carb adjustments. When adjusting "a full turn out" I just tighten both adjusters all the way down and just give 1 full turn my best guess? I'm guessing its not an exact science and I'll have to play with it on the water. Any other carb adjustment tips are welcome. Thanks!

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[bigmike585]

Took the ski out this evening for a trial run.

Pre adjusted carbs to 1 turn out when putting everything back together. Fired it up when I got to the lake and adjusted the idle to a desirable spot. Then I hopped on and gave it a try. Sluggish on the low end. Takes a second to get out of the water then once it hits a certain rpm, it wants to haul ass.

Anyone running these dual keihin setup? How do you adjust the back carb? I can't get a screw driver in there to turn it? Front carb is adjusted easy, its the mix screws on the rear carb that are hard to reach.

 

[bigmike585]

Also after I ran it around for about 20 minutes, it died and did not want to start again. It seemed to have too much fuel because when trying to start it, there was no need to give any throttle. When I'd crank on it for a while with no throttle, it would finally begin so start.

Once I'd get it started, it wouldn't stay running long. Definitely couldn't give it much throttle or it would just die. After it cooled down for awhile it seemed to wanna fire right back up and run good.

One thing should be noted, I mixed my fuel 40:1 because I didn't want to take any chances with engine lube. I haven't checked the spark plugs since I got off the water but tomorrow I'll see if they are oily or fouled looking. Could be that its just too rich on the low end.

One more thing, is the pisser on the port side of the bow supposed to piss with pressure? If so it seemed kinda weak. When it was dying I could hear steamy sizzling sounds from the pisser. So I beached it and popped the hood to see if it was hot. Nothing seemed abnormally hot so I'm guess I'm good there. ( dripped water on exhaust and cylinders and it didn't sizzle).

 

[bigmike585]

Ttt, about to pull it out of the garage

 

[Magyar68]

Actually now it sounds a little like your stator. This is Classic Stator failure behavior. Runs great til its hot then dies and is really hard to start and later won't start at all. You may want to test it. As for adjusting the Rear carb low adjuster, i always had to pull them unfortunately. Sluggish on the low end, Does your gas tank hold Pressure?

 

[bigmike585]

After alot of research, im thinking stator could be the culprit.

Yes gas tank holds pressure fine from what i can tell.

So, i just pulled the ebox off and opened it up. Dont really know how to test the components, never messed with this stuff before, but it cant be that hard. There is some funk, corrosion in the lower 1/4 of the ebox. I believe on the ignigtor, other than that it looks good.

Also just pulled the stator, not sure how to tell if its bad but thinking abiut sending it off to be rebuilt.

I'll post pics of the stator and ebox.

 

[bigmike585]

Ebox

 

[bigmike585]

Another ebox pic

 

[bigmike585]

Stator

 

[bigmike585]

I noticed the inside of the stator cover is nicked up from what looks like debris. Not sure what is normal doesnt appear to be severe. Some metal shavings are stuck to magnetic areas as well.

Any issues could have caused this or is it common?