Thread: carb problem
10-20-2007, 01:41 AM #1
hi guys just wondering if anybody has had a problem like this if i let my ski sit on the beach after a ride, if it sits for more than 15 - 20 minutes the ski will start no worrys pull half throtle no worrys but if i hit full throtle the ski bogs like its not getting enough fuel. After riding for 30 sec to 1 min ski runs awsome and wont miss a beat till next time it sits on the beach for a while. Now i fitted a new fuel filter checked fuel pumps replaced 2 creased clear disks in the pumps cleaned the filters in the cars and did a compresion test 150-145. Ran the ski last week same problem now it is doing my head in only thing i can think of is maybe leaking needle and seat anybody had this problem before
10-20-2007, 07:58 AM #2
check the check valve on top of the tank. make sure it only flows 1 way, and that the hoses attaching it aren't kinked.
10-20-2007, 10:41 AM #3
Definitely sounds like you are losing pressure. How are your carbs set-up on the side draft?
10-20-2007, 11:38 PM #4
I will try the valve later on to see if there is a problem with it. My carbs are on a riva sidedraft manifold pumps towards the front 1.5 n+s, 115 grm springs, 100 primary jets 1turn out, 120 main jets hi set 3/4 turn out. removed carbs and needle and seats they have slight wear marks where the needle sits on the seat but thats all i have found so far.
10-21-2007, 12:03 AM #5
Do a popoff test this will tell you if it is leaking, and be sure and check the o-ring around the seat too
10-22-2007, 09:40 AM #6
needle and seat checked out ok so i tested the check valve blew one way easy flow tryed the other way and could not blow. But still i wasnt satisfied so i tryed again but this time put the valve in a glass of water as i blew and bubles came out the other end very slightly. So that slight leak might explain why it only plays up after sitting on the beach for 15-20 minutes well i hope so anyway. I orderd a new one and will try it on the next hot day.
10-22-2007, 12:30 PM #7
What does your piston wash look like.
At first I was thinking a minor air leak but I think you might be overly rich.
To much fuel not to little.
Do you have chokes removed if so what does a few squirts of the primer do.
01-06-2008, 09:59 AM #8
you guts were know your stuff check valve on the fuel tank solved the problem. sorry i took my time but broke my ski before i had a chance to test it. cracked the block rear r/h cyl between the water jacket and the transfer port result water in the rear cylinder . tryed to weld the block with no success so picked up a second hand block and went with even biger port work, decked top reboared and fited new rings. so far run in the ski now need to tuned up and see if it will kick a$#.
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