IXLR8 Posted March 25, 2011 Share Posted March 25, 2011 I went to start my RT today after it has been sitting all winter. Engine turns over fine, no start. I don't hear the fuel pump and there is no reading on the fuel gauge. I vaguely remember something like this from years ago, did a search and didn't find anything. After a little trouble shooting, it seems the fuel pump relay is engaging for about 2 seconds after key is turned on, then it shuts off. There is power to the relay, but EKR line from the Motronic unit seems to be the culprit. It goes low for about 2 seconds after key is turned on then it floats high, low is needed to activate relay. Any idea's what the Motronic is looking for to bring this line low? Nearest dealer I trust is 120 miles away, any help would be appreciated. Thank you Link to comment
dirtrider Posted March 25, 2011 Share Posted March 25, 2011 Afternoon Jim Your pump ONLY runs for 2-3 seconds at key on, then it goes off UNTIL you start cranking the engine over. If your pump doesn’t run but the relay triggers for 2-3 seconds at key on then your problem is either an open between the pump & relay, no power to the B+ side of the pump relay, or your pump is stuck (more than likely a stuck impeller in the pump from sitting through storage) Added: with no fuel gauge working it could also be a high resistance or open ground. Check the pump connector for having power AND ground. You will only have pump power available for 2-3 seconds at key on (should have power all the time during engine cranking though) Also make sure the side stand is up. Also check fuse (6) as that supplies power to the pump control side of the relay (relay has two power inputs, one from ign switch for pull-in coil control, and B+ from fuse (6) for pump motor operation. Link to comment
IXLR8 Posted March 25, 2011 Author Share Posted March 25, 2011 Afternoon Jim Your pump ONLY runs for 2-3 seconds at key on, then it goes off UNTIL you start cranking the engine over. If your pump doesn’t run but the relay triggers for 2-3 seconds at key on then your problem is either an open between the pump & relay, no power to the B+ side of the pump relay, or your pump is stuck (more than likely a stuck impeller in the pump from sitting through storage) Added: with no fuel gauge working it could also be a high resistance or open ground. Check the pump connector for having power AND ground. You will only have pump power available for 2-3 seconds at key on (should have power all the time during engine cranking though) Also make sure the side stand is up. DR Thanks, I have power to the + side of the relay, I jumpered the relay contacts and no activity to the pump. Further troubleshooting shows the power to the injectors is also on for only those 2 seconds. I haven't checked to see if power is on while it is cranking. I was assuming that since the engine was cranking over.. the side stand switch was good. Sounding more like pump issues... how much work is it to pull the pump? Is it just the tupperware on that side... or does the tank need to come off? Thank you. Link to comment
Boffin Posted March 25, 2011 Share Posted March 25, 2011 Afternoon Jim Your pump ONLY runs for 2-3 seconds at key on, then it goes off UNTIL you start cranking the engine over. If your pump doesn’t run but the relay triggers for 2-3 seconds at key on then your problem is either an open between the pump & relay, no power to the B+ side of the pump relay, or your pump is stuck (more than likely a stuck impeller in the pump from sitting through storage) Added: with no fuel gauge working it could also be a high resistance or open ground. Check the pump connector for having power AND ground. You will only have pump power available for 2-3 seconds at key on (should have power all the time during engine cranking though) Also make sure the side stand is up. DR Thanks, I have power to the + side of the relay, I jumpered the relay contacts and no activity to the pump. Further troubleshooting shows the power to the injectors is also on for only those 2 seconds. I haven't checked to see if power is on while it is cranking. I was assuming that since the engine was cranking over.. the side stand switch was good. Sounding more like pump issues... how much work is it to pull the pump? Is it just the tupperware on that side... or does the tank need to come off? Thank you. The pump is inside the tank. Tupperware off, drain tank, tank off and turn over. There you will see a circular plate that holds the pump. At this point you really need a manual - removal of the plate needs care as the low-fuel level float is also on the assembly. The o-ring for the plate will have swollen and will need drying out before it will go back - I always fit a new one. Andy Link to comment
dirtrider Posted March 25, 2011 Share Posted March 25, 2011 Afternoon Again Jim It does sound like the pump but with that gauge also not working might point to a tank ground issue. OR, maybe corrosion at the tank to main harness connector (right rear of tank) I guess before actually removing the tank and pulling the pump I would access the tank to harness connector and check that for problems or being loose, then verify 12v power to that connector with enough current to run the pump, then verify the ground to the pump connector can handle the pump current. If you determine it IS the pump that is stuck you can pull the pump out, remove the fuel pick-up sock , then squirt something like WD-40 into the pump and pump armature area then use something like a dull dental pick to reach in and give the pump impeller a spin to break it free. Link to comment
Jim Moore Posted March 26, 2011 Share Posted March 26, 2011 If the fuel pump is coming on for a few seconds when you turn the key on, it's working properly. You say the guage reads zero. You have gas, right? What other indications do you have in the RID? Link to comment
dirtrider Posted March 26, 2011 Share Posted March 26, 2011 If the fuel pump is coming on for a few seconds when you turn the key on, it's working properly. You say the guage reads zero. You have gas, right? What other indications do you have in the RID? Morning Jim He (the OP) clearly states in his first post above that he didn’t hear the fuel pump run and in follow up post when he jumpered the pump relay supplying power to the pump it still didn’t run. Link to comment
IXLR8 Posted March 26, 2011 Author Share Posted March 26, 2011 Yup, fuel pump relay activates for 2-3 seconds but I never hear the pump even when I jumper the relay. Circumstances dictate I won't be able to work on it until next Wed at the earliest. I will start by finding the connector to the fuel pump/gauge sensor and make sure all looks good there. If that doesn't sort it out.. then pull tank and pump/sensor unit. I just changed the air filter and found a mouse had been making a home in there... this leaves me with a BAD feeling about the wiring. Link to comment
Jim Moore Posted March 27, 2011 Share Posted March 27, 2011 Got it. I misunderstood. So the relay clicks but the pump doesn't come on. Weird! Link to comment
IXLR8 Posted March 30, 2011 Author Share Posted March 30, 2011 I pulled the tupperware and found the connector for the fuel pump/gauge. I disconnected and re-seated it several times. Fuel gauge now works but pump still does not. I pulled the tank and removed the pump/gauge assembly. I removed the screen filter and the pump. With a small screwdriver I was able to manually turn the pump. I found that if I hooked the pump to power and manually gave the pump a push... it would run. If I disconnected and reconnected the power, it would not restart. I moved the pump manually a few times and hooked power up after each try... sometimes it would run, sometimes not. I called the nearest dealer I will do business with.. they have pump in stock $351. They are shipping it out Thursday to arrive on Friday... in the middle of a snow storm with a forecast 6-8" . At this rate I won't be riding until summer. Link to comment
dirtrider Posted March 30, 2011 Share Posted March 30, 2011 Afternoon Jim Sure sounds like a possible pump issue. I guess before spending all that money on a new pump verify that your pump is getting full voltage. Low supply voltage or a high resistance ground can make a pump real lazy like yours is acting. Link to comment
IXLR8 Posted March 30, 2011 Author Share Posted March 30, 2011 Afternoon Jim Sure sounds like a possible pump issue. I guess before spending all that money on a new pump verify that your pump is getting full voltage. Low supply voltage or a high resistance ground can make a pump real lazy like yours is acting. I had the pump sitting on a bench hooked directly to a 10A battery charger as a power source. I hope that is good enough. Link to comment
dirtrider Posted March 30, 2011 Share Posted March 30, 2011 Evening Jim Maybe yes maybe no. Really depends on the battery charger output and charger’s charging algorithm. Some chargers will others won’t. I guess I wouldn’t trust a battery charger to supply enough current to run that motor without using a battery in the circuit to force a steady output. Also a caution: that little motor is designed to be fuel cooled as fuel passes through it’s armature area to cool it. It only takes a VERY short time to burn one up if bench run when dry. Link to comment
IXLR8 Posted March 31, 2011 Author Share Posted March 31, 2011 Evening Jim Maybe yes maybe no. Really depends on the battery charger output and charger’s charging algorithm. Some chargers will others won’t. I guess I wouldn’t trust a battery charger to supply enough current to run that motor without using a battery in the circuit to force a steady output. Also a caution: that little motor is designed to be fuel cooled as fuel passes through it’s armature area to cool it. It only takes a VERY short time to burn one up if bench run when dry. DR- I knew the pump depended on the fuel for cooling, I didn't run it for long when it did run. But thanks for the caution. The pump was still full of fuel when it did run... as the puddle of fuel sprayed on my bench top proved. The other reason for thinking pump was not good was that it didn't turn very freely when I moved it manually. I will try it again tomorrow with a direct battery hookup to see if that makes a difference. Link to comment
IXLR8 Posted March 31, 2011 Author Share Posted March 31, 2011 This morning I hooked the fuel pump to a battery. Sometimes when I connected the battery the fuel pump clicked, sometimes not. Sometimes there was a spark when I connected the wire, sometimes not, it never did run. I had ordered a new pump from MAX's BMW in New Hampshire at 5:15 Wed afternoon, to be shipped UPS ground, it was delivered Thurs at 11:00am. Thanks MAX. I put in the new pump, it made all the correct noises when I turned the key on. When I tried to start the bike.. it fired right up. Now to put everything back together and wait for the snow to go away, we are forecast to get 8-12 inchs tomorrow. Thank you to all for the guidance and support to get this problem solved. Link to comment
bluesguitarboy Posted April 1, 2011 Share Posted April 1, 2011 $351.00 for a pump try this link. http://www.beemerboneyard.com/16141341231rk.html $145.00 is much better. Link to comment
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