1980 Intruder doesn't want to stay running - Fueling Issue???

[TWIN86GNS]

Gentlemen,

I purchased a 1980 Intruder at the end of last season and didn't get a chance to run it until this season.  It started and ran rough when I purchased it but it did run.  I started it numerous times through the summer and it seemed to run well after it ran for a bit.  We finally got snow this season, I (my son) rode it a bunch and put about 120 miles on it from the time that I purchased it but a couple of weeks ago it quit on my son (11 years old).  He had been riding near the house and had been going slow and he said that "it ran out of gas" but it had lots of gas in it so I put it in the garage and looked at it a few days later.  I figured he had fouled the plugs from running it pretty slow for a while so I figured new plugs and it would be good to go.  Purchased new plugs, went to install them but before I did I tried to start it and it started and ran, I took it up the road and back (very short distance) and it died on me in my driveway.  A few pumps of the primer and it would start up and run a bit and then die like it was out of fuel. 

I looked at it and see the fuel filter looks to be pretty old so I go buy a new fuel filter and some new fuel lines and install the new parts, the sled fires right up, runs for about 1 or 2 minutes and then dies like it is out of fuel.  Prime it, starts again and wants to die in 15 seconds or less.  Will stay running if you keep pumping the primer, any ideas of what I need to check?

I am thinking a fuel pump issue or ?  I need help with this so my son can get back out on this sled and have some fun.  I actually bought the sled to use for myself to go ice fishing but I haven't barely gotten to ride it yet.  The mileage on the sled is 2150 miles now.  I can use any and all ideas / help.

Thanks,

[rminier]

 It sure sounds like you are not getting enough fuel to carbs. Couple easy things to check before fuel pump is the impulse line (hose) that goes from a fitting on the crankcase to the fuel pump and creates the "pulses" that move the diaphragms in the pump. That hose needs to be perfectly leak-free so that the pulses generated are strong. Also might look at the fuel pickup tube that is inside the tank and goes to the intake side of fuel pump. After 35 years, that tube could have collapsed or the screen at the end (inside the fuel tank) could be plugged. Since finding this site a short time ago, I learned that the OEM fuel pumps for Kawasakis had an anti-siphon feature, but I replaced my original fuel pump on my 440 Invader quite some time ago with a standard dual outlet Mikuni pump, available lots of places pretty cheap, and it has worked fine. An air leak from the carb boots or the crankshaft seals could contribute to this problem. Any sled this old probably needs to have both of those things checked out, especially crank seals. Lots of help on this site if you decide to do that this summer. Be careful, if crank seals are bad you could suffer the dreaded piston seizure. Lastly, how clean are the carbs? Float height is probably O.K. since it ran well for awhile, but crud in the carbs could definitely prevent it from running right. Good luck getting the Intruder goin' again!

[rminier]

Oh, if you have not had the carbs apart yet on your Intruder, you should be aware that there is a small o-ring at the bottom of the needle jet and it fits down into the bottom of the float bowl. When these o-rings get old and rotten they leak too much fuel by and you can go crazy trying to get the sled running well. Learned this the hard way many years ago. These o-rings would not be contributing to your current problem, which sounds like a lack of fuel to the motor, but if they look bad when you have carbs apart, you may as well replace them. I found some years ago that fit great, but I don't remember the dimension. Maybe someone on here knows if they are still available from Kawasaki, or somewhere else.

[thomy]

If you do need the o-ring here are some part numbers:

Polaris part number 3130015
Marshall Distributing and Mikuni part number BV32/04
Western Power Sports part number 14-2215

Thom

[kawhead]

some of the earlier sleds had a small nickel sized filter inside the fuel pump that clogged easy.

[mswyka]

Sounds like everyone is on the  right track,  if it runs when primed it is clearly not getting fuel through the  fuel delivery system.  Impulse line and fuel pump are good things to check but I do have to ask  if you disassembled and cleaned  the carbs.  If  there is  crud in the carb bowl it is very easy for a float to stick or for  the  fuel needles themselves to stick.   While this usually only happens to one carb at a time, if not cleaned out, it could be happening on both sides.