RX3 Fuel Pump Fix

jodellus · 08-08-2019, 11:16 PM

Tried starting my RX3 after sitting idle for several months and it just cranked but did not start. Did not hear the fuel pump after turning the key.

The first thing I checked was the fuse and it was good. The next troubleshooting step was to pull the wire from under the tank and check the voltage when the key was turned on, it showed ~10v. So then I removed the tank and pulled the fuel pump out.

The first thing I saw is that the fuel strainer had just crumbled apart. Appears any fuel with Ethanol will eat away this filter. Will try to use only Non-Ethanol fuel from now on. I do this on all my bikes with carbs but thought that fuel injected bikes would not have an issue with standard Regular Unleaded that typically has Ethanol.

Tried putting some alligator clips on a battery and connecting the fuel pump motor and it was a no-go, did not hear anything. Had read elsewhere that tapping the motor sometimes can knock whatever is freezing up the motor. Tried some light taps and still a no-go. As a last ditch effort I slammed it pretty hard on the concrete, connected the battery again and it whizzed up like it should. Did several more tests and the motor spun up up like it should. Note that I had removed the motor from the plastic part of the fuel pump to test.

After I reassembled the pump, still needed to replace the fuel strainer. Found one at Advance Auto that was close and filed down the plastic nipple on the pump to fit into the new fuel strainer.

After putting the fuel pump back in the tank I plugged everything back in, added some Non-Ethanol fuel and tried to start. The fuel pump whizzed as normal but it still just cranked but did not start.

Just to check I pulled the plug and it had good spark. Then I tried pulling the fuel injector to see if it had a good spray when cranking. The injector spray was very light, not nearly enough to start. Then I removed the fuel line from the injector and tried cranking and it was barely dripping. Just to check I lifted the tank found that the fuel line from the tank was folded over, once I fixed the kink, fuel started flowing out of the line I removed from the injector.

After putting the fuel line on the injector I tried cranking again it had a good spray. I was just putting the injector in a jar to see the spray. After putting the injector back in the throttle body tried cranking and it started right up.

Not sure how long the motor in the fuel pump will last but I have used the bike several times since putting the fuel pump back and the bike has started without any issues.

Hope this helps, I did not see many posts on removing and working on the RX3 fuel pump.

08-08-2019, 11:16 PM	#1
jodellus Join Date: Feb 2016 Posts: 3	RX3 Fuel Pump Fix Tried starting my RX3 after sitting idle for several months and it just cranked but did not start. Did not hear the fuel pump after turning the key. The first thing I checked was the fuse and it was good. The next troubleshooting step was to pull the wire from under the tank and check the voltage when the key was turned on, it showed ~10v. So then I removed the tank and pulled the fuel pump out. The first thing I saw is that the fuel strainer had just crumbled apart. Appears any fuel with Ethanol will eat away this filter. Will try to use only Non-Ethanol fuel from now on. I do this on all my bikes with carbs but thought that fuel injected bikes would not have an issue with standard Regular Unleaded that typically has Ethanol. Tried putting some alligator clips on a battery and connecting the fuel pump motor and it was a no-go, did not hear anything. Had read elsewhere that tapping the motor sometimes can knock whatever is freezing up the motor. Tried some light taps and still a no-go. As a last ditch effort I slammed it pretty hard on the concrete, connected the battery again and it whizzed up like it should. Did several more tests and the motor spun up up like it should. Note that I had removed the motor from the plastic part of the fuel pump to test. After I reassembled the pump, still needed to replace the fuel strainer. Found one at Advance Auto that was close and filed down the plastic nipple on the pump to fit into the new fuel strainer. After putting the fuel pump back in the tank I plugged everything back in, added some Non-Ethanol fuel and tried to start. The fuel pump whizzed as normal but it still just cranked but did not start. Just to check I pulled the plug and it had good spark. Then I tried pulling the fuel injector to see if it had a good spray when cranking. The injector spray was very light, not nearly enough to start. Then I removed the fuel line from the injector and tried cranking and it was barely dripping. Just to check I lifted the tank found that the fuel line from the tank was folded over, once I fixed the kink, fuel started flowing out of the line I removed from the injector. After putting the fuel line on the injector I tried cranking again it had a good spray. I was just putting the injector in a jar to see the spray. After putting the injector back in the throttle body tried cranking and it started right up. Not sure how long the motor in the fuel pump will last but I have used the bike several times since putting the fuel pump back and the bike has started without any issues. Hope this helps, I did not see many posts on removing and working on the RX3 fuel pump.
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