- Location
- NW Florida Gulf of Mexico
I thought I got a good deal on 2 running Kawasaki ST 3 seaters....
Twin cylinder single jug, single carb , factory everything
Crankcases say JT750AE, jug circle # is 22
1 ski run ok.
The 2nd ski ...Diesels at 10,000+ rpm on trailer when flushing if you snap the throttle.
Even snatching the plug wires off the engine dont stop it.
...Hot piston tops dont need no spark plug to light gasoline.
Stuff the carb with a T-shirt or wait till the fuel cut valve kicks in is the only way I got it to quit.
Never did that on the water thankfully tho.
After buying 2 gasket + seal rebuild kits for piece of mind I tore them both down for inspections.
I'm no stranger to mechanics,V8 jeeps,guns,motorcycles,grew up poor,learned to build it.
Put a new rear crank bearing + a WSM top end kit in a 2001 Yamaha 800XL .
A few 1200GP's I put gaskets on and tuned, ect.
Somehow I never owned 1 of these giant weed whippers myself tho...
1st ski was burning nice in both chambers....but , the piston tops read .75 rear + .50 in the front.
That ski was running good enough and just getting resealed + painted....tada , grab the cooler.
The 2nd engine....rear piston had a rub embedded lower ring and definite pitting signs of running lean.
Ring is still stuck in the piston, flushed in 1 spot
Inner cylinder damage was honeable.
The jugs are also 1/3 Packed (petrified) with salt sand corrosion sediment.
Jugs lower exhaust/water manifold ports walled up to the gaskets on both sides.
2 days of picking and scraping I still couldn't hole through it anywhere.
I also noticed a section of the exhaust/water port that eroded away allowing a 1/16 warm water hull leak.
>That jug set is just Gone and replacement is it's only hope.
Noticed the crankcase drain valve was still on this engine and had Not been blocked off like the other engine. It was obvious it wasn't doing it's job properly and providing a huge air leak.
I believe thats the reason this single carb twin thumper went so drastically lean just on the 1 rear cylinder.
Seems 1 spring valve operated the 2 ports in the crank case with the help of some small reeds simultaneously by design.
The 1st engines going back together fine as I get the time to tinker with it.
I cleaned, painted, + lube stacked the 2nd engine back without the pistons just to keep it together till I find the solution .
My Found Choices so far .....
>Ebays averaging $150 jugs + pistons used , all of it is recommended boring or I don't like the images after inverting the colors on Gimp. (...kinda like an image X-ray)
>SBT top end exchange, $475
>Craigslist 150miles away...$450 for a used complete engine.
Says compressions good and it runs.
What I think I've learned about the 750.....
1995 Kawasaki decided to beef up the rod thickness and started a new revised reproduction in sea foam green colored block versions of the 750.
....supposedly a few 95 big pins were produced in gray that year of change.
The older smaller pin (rod) engine versions were gray metallic in color .
The small pins supposedly have 10 lower intake mounting bolts while the big pin engines have 12.
The big pin + small pin pistons are different and wont interchange due to rod/wrist pin thickness.
The timing is also different because Kawasaki changed the port placement slightly on the newer versions.
The main (long block) parts being of structural changes will not allow interchangeability between the big pin and small pin versions.
Something about the circle impressions cast into the jugs with the #'s in them (mines 22) tells the porting/size differences in the jug assemblies???
Questions ?
SBT's website exchange offer Title Says :
"Kawasaki Cylinder Exchange Kit 750 Small Pin 750 SS /SS XI /XIR /ST 1992 1993 1994 1995 "
Are those pre 1995 Kawasaki 750 Small Pin SS /SS XI /XIR /ST models interchangeable?
Whats the most common inexpensive (carb'd) Kawasaki ski engine to find parts for still?
I ask because I see those "Kawasaki Jet Ski JRE Engine Conversion Adapter Plates" on ebay for $110
The seller has 209 sold in a week.
If say a 500cc is more common then these 750's, I'd gopher that.
Reliability, simplicity, + cost is much more desired over the power .
I just want a couple fishing scooters not rockets.
So whatcha think I should do ?
Twin cylinder single jug, single carb , factory everything
Crankcases say JT750AE, jug circle # is 22
1 ski run ok.
The 2nd ski ...Diesels at 10,000+ rpm on trailer when flushing if you snap the throttle.
Even snatching the plug wires off the engine dont stop it.
...Hot piston tops dont need no spark plug to light gasoline.
Stuff the carb with a T-shirt or wait till the fuel cut valve kicks in is the only way I got it to quit.
Never did that on the water thankfully tho.
After buying 2 gasket + seal rebuild kits for piece of mind I tore them both down for inspections.
I'm no stranger to mechanics,V8 jeeps,guns,motorcycles,grew up poor,learned to build it.
Put a new rear crank bearing + a WSM top end kit in a 2001 Yamaha 800XL .
A few 1200GP's I put gaskets on and tuned, ect.
Somehow I never owned 1 of these giant weed whippers myself tho...
1st ski was burning nice in both chambers....but , the piston tops read .75 rear + .50 in the front.
That ski was running good enough and just getting resealed + painted....tada , grab the cooler.
The 2nd engine....rear piston had a rub embedded lower ring and definite pitting signs of running lean.
Ring is still stuck in the piston, flushed in 1 spot
Inner cylinder damage was honeable.
The jugs are also 1/3 Packed (petrified) with salt sand corrosion sediment.
Jugs lower exhaust/water manifold ports walled up to the gaskets on both sides.
2 days of picking and scraping I still couldn't hole through it anywhere.
I also noticed a section of the exhaust/water port that eroded away allowing a 1/16 warm water hull leak.
>That jug set is just Gone and replacement is it's only hope.
Noticed the crankcase drain valve was still on this engine and had Not been blocked off like the other engine. It was obvious it wasn't doing it's job properly and providing a huge air leak.
I believe thats the reason this single carb twin thumper went so drastically lean just on the 1 rear cylinder.
Seems 1 spring valve operated the 2 ports in the crank case with the help of some small reeds simultaneously by design.
The 1st engines going back together fine as I get the time to tinker with it.
I cleaned, painted, + lube stacked the 2nd engine back without the pistons just to keep it together till I find the solution .
My Found Choices so far .....
>Ebays averaging $150 jugs + pistons used , all of it is recommended boring or I don't like the images after inverting the colors on Gimp. (...kinda like an image X-ray)
>SBT top end exchange, $475
>Craigslist 150miles away...$450 for a used complete engine.
Says compressions good and it runs.
What I think I've learned about the 750.....
1995 Kawasaki decided to beef up the rod thickness and started a new revised reproduction in sea foam green colored block versions of the 750.
....supposedly a few 95 big pins were produced in gray that year of change.
The older smaller pin (rod) engine versions were gray metallic in color .
The small pins supposedly have 10 lower intake mounting bolts while the big pin engines have 12.
The big pin + small pin pistons are different and wont interchange due to rod/wrist pin thickness.
The timing is also different because Kawasaki changed the port placement slightly on the newer versions.
The main (long block) parts being of structural changes will not allow interchangeability between the big pin and small pin versions.
Something about the circle impressions cast into the jugs with the #'s in them (mines 22) tells the porting/size differences in the jug assemblies???
Questions ?
SBT's website exchange offer Title Says :
"Kawasaki Cylinder Exchange Kit 750 Small Pin 750 SS /SS XI /XIR /ST 1992 1993 1994 1995 "
Are those pre 1995 Kawasaki 750 Small Pin SS /SS XI /XIR /ST models interchangeable?
Whats the most common inexpensive (carb'd) Kawasaki ski engine to find parts for still?
I ask because I see those "Kawasaki Jet Ski JRE Engine Conversion Adapter Plates" on ebay for $110
The seller has 209 sold in a week.
If say a 500cc is more common then these 750's, I'd gopher that.
Reliability, simplicity, + cost is much more desired over the power .
I just want a couple fishing scooters not rockets.
So whatcha think I should do ?
