Hard start - no start problem

Just starting having a problem with my 1995 - K75. Started it up just fine and pulled it out of the garage to warm up while I got my gear on. When I got on and gave it throttle, the motor died. Would not start back up. After trying to start it for about 10 minutes, it fired right up and ran great. When I got back it would not start again. The next day it still would not start , but after 10 - 15 minutes it started and ran fine. Took it to the dealer and was told that the fuel pump fuse was blown and to come get it. It started right up and I took it to fuel up. After fueling was hard to start, but started after about 5 minutes. After about a 50 mile ride and really kicking it in the gut, the bike ran great. I got home and turned it off - started right up twice - the third time it would not start and has not started since. Any help would be greatly appreciated!

hard to start

had that problem with an 86 k75--was a loose wire under a relay in the relay box

Gonna be a tough one to troubleshoot by remote control. Especially since it's intermittent (when it breaks for good - then it's easy to find..)

Things that come to mind:

1 - Why was the fuel pump fuse blown? I'd be looking at the wiring going to the tank (right rear side) and making sure no bare wires, nothing pinched.

2 - Do you HEAR the fuel pump when cranking it (I assume it does crank.. dunno for sure since that isn't clear in your writeup)?

Engines need 5 things to run:

1. Air - to use the oxygen to support combustion
2. Fuel - to burn
3. Ignition - to fire off the burning mixture
4. Compression - to put all the mixture where it will do some good
5. Exhaust - someplace for the results to go

Since the K75 is noted for fouling sparkplugs if it doesn't start immediately - and not starting at all until the wet plugs are removed/replaced, I'm making a WAG that your problem is fuel related.. but we want to check this:

Next time it fails to start - remove a plug and check if it's wet. You can prepare for this by removing the plug gallery cover at home, and carrying a plug wrench and pliers to pull the spark-plug-cap off the plug.

• If the plug is wet - your problem is #3 - no ignition. We can start checking ignition parts - probably looking closely at the HES since it's the most common failure part.
• If the plug is dry - your problem is #2 - no fuel.
  
• If no fuel - that's when you want to know if you hear the fuel pump running when you press the starter (put your ear against the tank..)
  
  • If you DON'T hear the fuel pump - then we have to troubleshoot the fuel-pump wiring.
  • If you DO hear the fuel pump - then further diagnostics at the injector wiring is needed.

Oh - one thing to try - and this is flailing a bit - disconnect and reconnect the big connector to the ECU L-Jetronic box under the seat a few times. Make sure it clicks firmly into place. More than once this has cured this sort of intermittent - the contacts get dirty, and connecting/disconnecting them wipes them clean.

Thanks for the reponse. The latest is that I just went to the garage and hit the switch - started right up. The bike has not been moved or touched in a day since it would not start. How strange is that.

dr010459 said:

Thanks for the reponse. The latest is that I just went to the garage and hit the switch - started right up. The bike has not been moved or touched in a day since it would not start. How strange is that.

Click to expand...

Not strange at all if the ignition switch is flakey.

Flakey ignition key will not allow the starter to crank the engine over. My understanding of the problem is - (and I could be all wrong here) - the engine cranks buy doesn't start.

The engine cranks over easily everytime I hit the switch. The battery is strong. When it doesn't want to start I do get the fant smell of fuel coming from the exhaust. Thanks

It amost seems like one of the injectors gets stuck open after running a little while and is allowing too much fuel into the cylinders when I try to restart the engine. But, as I said earlier, the bike runs great once it starts, never stalls and never hesitates, solid throttle through all gears and all rpm's.

Although it's not consistant with fuel odor in the exhaust, I have seen a few fuel injector relay failures lately on some early K bikes. Intermittant and otherwise.