1 Flooding, injectors open but not pulsing, Solved. Tue Mar 28, 2017 9:57 pm
Lucky
active member
Hi all,
I thought I'd share my experience in trying to get my K100rs started in the hope that it may help others down the track. I trawled through heaps off threads on this forum and others in trying to gather info and found that a lot of threads were never solved or maybe they were and some forgot to update their thread.
When I purchased my bike I knew it would not start. It is a good clean bike. Only 44,000km. Hardly used. I thought it can't be too hard to get it going. It had been sitting for 8-10 years I estimated after looking at the date on the tyres and the state of the inside of the fuel tank. The bike looked great on the outside but inside of the tank was terrible! The fuel pump was gummed up with gunk and it didn't even have a vibration damper around it anymore. It had disintegrated into a gooey mess on the bottom of the tank. The strainer was also shot.
I got stuck into cleaning the tank. Replaced fuel pump, vibration damper, strainer, all fuel and breather hoses. I had the injectors serviced and found 2 of the 4 were not that great and further testing found a third not playing the game all the time. It was on the way out. So I started researching injectors and reading lots of threads here again. I ended up running with injectors out of a Hyundai.
So with a fresh Motobatt battery, spark plugs, fluids and filters it was all systems go. Time to crank her over for the first time.....
Well that didn't go to plan....
She seemed to start for a second or so and then cut out. I tried again. Didn't want to start at all this time....Hmmmm. I then noticed fuel dripping out the end of the header pipes. This isn't good. Out came the spark plugs to dry everything out. Next day I did the same and the bike behaved the same. There was way too much fuel being delivered.
I studied the forums some more and subsequently cleaned all electrical connections and ordered a new fuel pressure regulator as I didn't have the testing gear to test mine. Given there had been stale fuel in it for years I thought it was possible that the FPR had been damaged. It was the only part of the entire fuel line I overlooked when replacing it all. I whacked the new FPR on and got all excited ready to start her up. Hit the starter and the same symptoms as before were still present. She'd start for a second and then flood. Bugger....
Next came testing the coolant temperature sensor. Many threads spoke about this being a problem along with ground/earth issues and electrical connections. The coolant temperature sensor tested ok but I purchased another one just incase and it tested the same (I now have a spare). Rechecked and cleaned all connections and earth/ground wires. checked coils and leads and tested for spark. All good. I got all excited again and hit the starter. Still the same symptoms. Backfired and flooded. Damn you bike!!
I pulled the injectors out but still attached to the fuel rail to see if the injectors were pulsing. I could almost guarantee that they weren't given the amount of fuel dripping from the header pipes after a couple short starts. Yep, the injectors open for the full 1.5 seconds or so while the pump was working after hitting the starter. There was no pulsing. Heaps of fuel! It was dumping in! Ok what next I thought....
Back to the study ...
The ECU is getting a wrong signal from somewhere or the ECU is shot. The ECU was a quick and easy test so that was what I tried first before the next on the list, the Hall sensor and air flow meter. I called a mate of mine and asked to try his. Plugged it in and got everything ready for a start. Well I got the shock of my like when it started up with what felt like a half press of the start button. WOW!!!! I couldn't believe it. There wasn't even that much smoke. No where near what I was expecting. I'm up and running. Ended up being a very easy fix.
Just goes to show that even though it may not be common for an ECU to fail....they do. A simple test may save a bit of time and money....
All the reading and study has equipped me well for any future problems I suppose....
I thought I'd share my experience in trying to get my K100rs started in the hope that it may help others down the track. I trawled through heaps off threads on this forum and others in trying to gather info and found that a lot of threads were never solved or maybe they were and some forgot to update their thread.
When I purchased my bike I knew it would not start. It is a good clean bike. Only 44,000km. Hardly used. I thought it can't be too hard to get it going. It had been sitting for 8-10 years I estimated after looking at the date on the tyres and the state of the inside of the fuel tank. The bike looked great on the outside but inside of the tank was terrible! The fuel pump was gummed up with gunk and it didn't even have a vibration damper around it anymore. It had disintegrated into a gooey mess on the bottom of the tank. The strainer was also shot.
I got stuck into cleaning the tank. Replaced fuel pump, vibration damper, strainer, all fuel and breather hoses. I had the injectors serviced and found 2 of the 4 were not that great and further testing found a third not playing the game all the time. It was on the way out. So I started researching injectors and reading lots of threads here again. I ended up running with injectors out of a Hyundai.
So with a fresh Motobatt battery, spark plugs, fluids and filters it was all systems go. Time to crank her over for the first time.....
Well that didn't go to plan....
She seemed to start for a second or so and then cut out. I tried again. Didn't want to start at all this time....Hmmmm. I then noticed fuel dripping out the end of the header pipes. This isn't good. Out came the spark plugs to dry everything out. Next day I did the same and the bike behaved the same. There was way too much fuel being delivered.
I studied the forums some more and subsequently cleaned all electrical connections and ordered a new fuel pressure regulator as I didn't have the testing gear to test mine. Given there had been stale fuel in it for years I thought it was possible that the FPR had been damaged. It was the only part of the entire fuel line I overlooked when replacing it all. I whacked the new FPR on and got all excited ready to start her up. Hit the starter and the same symptoms as before were still present. She'd start for a second and then flood. Bugger....
Next came testing the coolant temperature sensor. Many threads spoke about this being a problem along with ground/earth issues and electrical connections. The coolant temperature sensor tested ok but I purchased another one just incase and it tested the same (I now have a spare). Rechecked and cleaned all connections and earth/ground wires. checked coils and leads and tested for spark. All good. I got all excited again and hit the starter. Still the same symptoms. Backfired and flooded. Damn you bike!!
I pulled the injectors out but still attached to the fuel rail to see if the injectors were pulsing. I could almost guarantee that they weren't given the amount of fuel dripping from the header pipes after a couple short starts. Yep, the injectors open for the full 1.5 seconds or so while the pump was working after hitting the starter. There was no pulsing. Heaps of fuel! It was dumping in! Ok what next I thought....
Back to the study ...
The ECU is getting a wrong signal from somewhere or the ECU is shot. The ECU was a quick and easy test so that was what I tried first before the next on the list, the Hall sensor and air flow meter. I called a mate of mine and asked to try his. Plugged it in and got everything ready for a start. Well I got the shock of my like when it started up with what felt like a half press of the start button. WOW!!!! I couldn't believe it. There wasn't even that much smoke. No where near what I was expecting. I'm up and running. Ended up being a very easy fix.
Just goes to show that even though it may not be common for an ECU to fail....they do. A simple test may save a bit of time and money....
All the reading and study has equipped me well for any future problems I suppose....