emartindale
New Member
So I'm the third person who thought they could fix this ski, but I'm beginning to think otherwise...
This is my first ski, but not my first small engine. I've rebuilt mowers, but I am far from infallable. The short version is that it runs on the trailer, but not in the water.
Two owners ago (as far back as I have even a verbal history) claims to have replaced the pump and wear ring, rebuilt the motor's PTO-side top end, and replaced the fuel lines. There is plenty of blue RTV between the pump and hull, and there is dried sealant under the coupler inside the hull. There is also a newer gasket under the PTO side cylinder. This owner sold (according to the guy who bought it from him) because he installed a single carb setup and was not able to tune out a high idle and poor performance.
I purchased it this past weekend barely running and obviously having been worked over by the most recent previous owner. This owner had replaced a single carb with correct dual square carbs from ebay. He had also "fixed" the fuel line routing. He said that he ran the ski in the water (still on the trailer), but it wouldn't stay running. The symptoms when I purchased it were that (on the trailer out of the water) it would run for about about 1 second unless nursed with the throttle, and then it might make 3-5 seconds.
I split a Mikuni carb kit (not including needles/seat) between both carbs rebuilding the pump side of the MAG carb, and the diaphram side of the PTO carb. Most of the soft parts looked good and the passages cleaned up, though the carbs were very dirty internally, and the internal filter was missing from the MAG carb. The MAG carb flowed fuel through the pump and out the nipple to the PTO carb. Until I got kind of aggressive with adjusting the Needle Valve Lever, I couldn't get fuel to flow through the PTO carb, though. Now it will flow through the PTO carb outlet nipple, but not very fast (which I think may be due to the "internal orifice").
I learned that one of the POs had routed the Supply line from the tank->switch->filter->PTO carb exit, and the Return line was on the inlet to the MAG carb. I also learned that one of the POs had connected the pump coolant line directly to the head, so the tuned pipe was getting no water.
To date, I have:
-Rebuilt the carbs (though I have a mediocre success rate with small engine carbs)
-Routed "ON" fuel lines as follows: Tank->switch->filter (cleaned, but not replaced)->MAG carb->PTO carb->Tank "Return"->
-Routed "RES" fuel lines as above
-Routed "Vent" to a short bit of fuel line that vents to atmosphere
-Corrected cooling water routing from pump->tuned pipe (split to two nipples on the pipe). Nipple on top of pipe goes down to a lower point on the pipe. Nipple on top of head goes to "pisser." Large nipple on rear of head goes to port that appears to exit behind the pump. Larger nipple on rear of head goes to exhaust port
-Tested compression using old tester that I don't trust too much, and only finger tight. It reads just over 125 on both.
After this work, the ski will start and idle on the trailer (usually w/o choke as it's 90F+). From about 1/3 throttle, it missed and ran poorly, but I believe that is my high speed screw. I had it out to replace the o-ring, so the 1/4 turn index is shot. It's at about 1/2 turn out now. My low speed screw was set at 1 1/4 turns out. I had planned to set the idle, slow speed and high speed screws in the water, but once in the water, it will not run. No combination of choke or throttle (or adjustments to the low speed screw) made it run in the water. I poured pre-mixed fuel in each chamber to get it running. Then I could usually keep it running for 30-60 seconds with the throttle, but then it would shut down only to not start again. The plugs before adding fuel directly, were slightly damp, but not flooded wet.
I have some fuel lines securd with zip ties, but when I pressurize the fuel tank, I don't hear any leaks when my finger is over the vent tube. Even keeping my finger on the vent tube after pressurizing the tank wouldn't keep the ski running in the water. It runs fine up to 1/3 throttle on the trailer with the open vent tube.
I'm charging the battery after a failed lake test. Any ideas?
I was trying to have a toy for the family to play with at the lake for a long weekend vacation starting tomorrow...
This is my first ski, but not my first small engine. I've rebuilt mowers, but I am far from infallable. The short version is that it runs on the trailer, but not in the water.
Two owners ago (as far back as I have even a verbal history) claims to have replaced the pump and wear ring, rebuilt the motor's PTO-side top end, and replaced the fuel lines. There is plenty of blue RTV between the pump and hull, and there is dried sealant under the coupler inside the hull. There is also a newer gasket under the PTO side cylinder. This owner sold (according to the guy who bought it from him) because he installed a single carb setup and was not able to tune out a high idle and poor performance.
I purchased it this past weekend barely running and obviously having been worked over by the most recent previous owner. This owner had replaced a single carb with correct dual square carbs from ebay. He had also "fixed" the fuel line routing. He said that he ran the ski in the water (still on the trailer), but it wouldn't stay running. The symptoms when I purchased it were that (on the trailer out of the water) it would run for about about 1 second unless nursed with the throttle, and then it might make 3-5 seconds.
I split a Mikuni carb kit (not including needles/seat) between both carbs rebuilding the pump side of the MAG carb, and the diaphram side of the PTO carb. Most of the soft parts looked good and the passages cleaned up, though the carbs were very dirty internally, and the internal filter was missing from the MAG carb. The MAG carb flowed fuel through the pump and out the nipple to the PTO carb. Until I got kind of aggressive with adjusting the Needle Valve Lever, I couldn't get fuel to flow through the PTO carb, though. Now it will flow through the PTO carb outlet nipple, but not very fast (which I think may be due to the "internal orifice").
I learned that one of the POs had routed the Supply line from the tank->switch->filter->PTO carb exit, and the Return line was on the inlet to the MAG carb. I also learned that one of the POs had connected the pump coolant line directly to the head, so the tuned pipe was getting no water.
To date, I have:
-Rebuilt the carbs (though I have a mediocre success rate with small engine carbs)
-Routed "ON" fuel lines as follows: Tank->switch->filter (cleaned, but not replaced)->MAG carb->PTO carb->Tank "Return"->
-Routed "RES" fuel lines as above
-Routed "Vent" to a short bit of fuel line that vents to atmosphere
-Corrected cooling water routing from pump->tuned pipe (split to two nipples on the pipe). Nipple on top of pipe goes down to a lower point on the pipe. Nipple on top of head goes to "pisser." Large nipple on rear of head goes to port that appears to exit behind the pump. Larger nipple on rear of head goes to exhaust port
-Tested compression using old tester that I don't trust too much, and only finger tight. It reads just over 125 on both.
After this work, the ski will start and idle on the trailer (usually w/o choke as it's 90F+). From about 1/3 throttle, it missed and ran poorly, but I believe that is my high speed screw. I had it out to replace the o-ring, so the 1/4 turn index is shot. It's at about 1/2 turn out now. My low speed screw was set at 1 1/4 turns out. I had planned to set the idle, slow speed and high speed screws in the water, but once in the water, it will not run. No combination of choke or throttle (or adjustments to the low speed screw) made it run in the water. I poured pre-mixed fuel in each chamber to get it running. Then I could usually keep it running for 30-60 seconds with the throttle, but then it would shut down only to not start again. The plugs before adding fuel directly, were slightly damp, but not flooded wet.
I have some fuel lines securd with zip ties, but when I pressurize the fuel tank, I don't hear any leaks when my finger is over the vent tube. Even keeping my finger on the vent tube after pressurizing the tank wouldn't keep the ski running in the water. It runs fine up to 1/3 throttle on the trailer with the open vent tube.
I'm charging the battery after a failed lake test. Any ideas?
I was trying to have a toy for the family to play with at the lake for a long weekend vacation starting tomorrow...
