1980 intruder 440 starts and runs but dies after 15min

[Robodave]

I have a 1980 Kawasaki intruder 440 F/C, with electric start, I have been trying to get it going and am at the point where it runs pretty good, it does not have as much power as the other intruder I have but I think that 's because it needs bigger jets and some tuning. But I can't get any farther because it runs for 15 min and than I experience a loss of power and it stays in place bogging and than dies. I have some experience working on these things but have never heard of something like this, if anyone has any ideas let me know.

[mswyka]

Good morning.  A couple of questions:

1.  Does it start right back up?  Or does it take some time before it starts again?
2.  Is the tank vent clear?
3.  How is your compression?

[Interceptor398]

Welcome to the site!!  What is the condition of the gas line all the way from the one in the tank to the carbs?  I have seen the plunger style primers leak air and cause those symptoms. There will be air bubbles moving in the gas lines if the primer is leaking air.  Go with the simple stuff first.

[Robodave]

I can't get it started after it dies, I pulled it like a hundred times, and the engine would barely catch, after a few hours it starts up again.
I checked the tank and no debris, I didn't see a filter on the end of the hose though. It was just a metal weight. I do have an inline filter before the fuel pump though and it seemed clean. I don't know what the compression is and I don't have a tester, but the top end gaskets were done about two years ago.
I will also try to get it started and look for bubbles in the line, also the fuel line from the fuel pump to the carbs looks new, it is possible that the line is the wrong size. What is the correct size for fuel line?
 

[Robodave]

Ok I went out and it started first two pulls, it idled at 3000rpm when it was cold, and it ran great. After I drove it around for 5 min and it had warmed up fully it started to lose power and started to bog, it also idled at 2000rpm after it was warm, it was not to the point of bogging and dying but it had just started to lose power, and the longer I ride it the worse it gets until it dies. I did not see any bubbling in the lines it looked clear to me, but I did notice that when I prime it fuel comes out of the top of the primer. Should I continue to ride it and continue to check for bubbles until it dies again? also it has a regular style primer not a plunger style one.

[Robodave]

Ok so I figured out what the problem was. The primer was broken and was dumping fuel into the carbs through the primer nipples, causing it to flood and die. So I had a new primer from the invader project that I am working on, put that in and it ran like new. thanks so much for steering me in the right direction, I never would have thought to look at the primer for engine problems.

[Interceptor398]

Va hooo!!

[MillerTime4242]

Mine does the same thing! I’ve never messed with the primer. Can I just clamp the line and see if that helps?

[gixxer6]

Mine does the same thing! I’ve never messed with the primer. Can I just clamp the line and see if that helps?

Yes.