Donvito

Mine has been pumping into a can a ground level but just to simulate resistance I elevated the can about 4.5 feet above the pump which is about 2 psi and it still pumped into it with no problem. But, thanks for the thought.

Thanks. Just took some readings to test all the fuses and this is what I found. Battery is 12.13, All fuses are between 11.1 and 11.2. The pump relay was at 9.8 while I tested. So, then what you said seems likely being the drop is consistent across all the circuits. How does the ignition switch operate and should I clean it somehow? I will check the main fuse now. Also, I just ordered a new fuse box from skydoc to upgrade the fuses.

Thanks to all for the advice. I am going to start at the beginning and try to find the reason for the voltage drop at the fuse box. I still have the original one. I will also test across the kill switch but I am going to remove the switch and do the maintenance on the switches and cables. Have never done it to the right side so not looking forward to it but the step by step instructions are helpful and I can lubricate the cables while I'm in there. Thanks.

11.3 left and 11.28 right, at battery terminals voltage is 12.3.

I've been troubleshooting an intermittent fuel supply problem to the carbs. Currently, the pump is set to pump into a gas can so all testing has been done without the engine running. So far, I have determined the problem is not the fuel supply, the pump, the relay or the fuel pump power wire, L/B, going from the relay to the pump. When I power the pump through the relay connection, with the relay removed, directly from the battery, it will pump until I remove the power. However, when I apply a jumper from the R/W wire at the relay connection to the pump wire, L/B, it will pump briefly and then stop and the voltage drops to below 10. So, what could cause a 2 volt power drop? I believe it could be the kill switch and I think there is a way to test resistance across it but I'm not sure how or where to do it. Anything else? Any advice is appreciated.

Thanks for the suggestion. I know the pump operates when it's getting 12 volts to it. So, after I drain the tank and check the petcock I'll confirm the pump operation. Since you understand the pump operation, what does it do when the fuel flow is not sufficient due to an obstruction in the supply system?

Yesterday, I was tying to cause the problem so I ran the bike with the fuel petcock closed until it stalled. I wanted to empty the carbs so the pump would operate. After doing this, I forgot to reopen the petcock and had 10 volts at the relay which caused the relay to click and vibrate, which is the same thing it was doing when the bike wouldn't run. When I opened the petcock, the pump operated and the voltage returned to 12. Currently I have 12 volts at the test points. I'm pretty sure I can cause the problem again by closing the petcock and running the bike until it stalls but I don't know if I could cause damage by doing it. Even though I have disconnected the fuel line from the pump and drained fuel at what seemed to be sufficient flow, I think I should drain the tank and check the screens at the petcock in addition to continuing to check the electrical system. I had assumed a restricted fuel flow had no effect on the relay voltage but now I'm rethinking that. What do you think and what should I check next?

OK, I don't have small enough connectors to make a jumper so have to buy some. I did notice something that you may be able to explain. With the petcock closed, the voltage drops 2 volts at the R/W wire at the relay and at the wire going to the pump. This happens whether the engine is running or not. So, if I turn on the key with the petcock closed, the relay will click and the voltage is at about 10. Then, when I open the petcock, after a few minutes, the voltage goes back to normal and the pump operates. Any thoughts? Have to go to work. Keeps getting in the way of working on the bike.

Thank you for the offer. Not sure it's the relay at this point but if everything points to that, I'll take you up on your offer to confirm that's the problem before I buy one. Thanks for the info about the cruise control and, yes, I have it.

I have 12 volts at the plug but only from one of the R/W wires, the other has no voltage. I'm testing with the plug unplugged, the key on and the bike not running. Trying to trace the wires on the schematic, it looks like one goes to the sidestand switch and the other to the ignition coils, is that correct? Why wouldn't there be power to one of the wires? I also tried testing with the start button pushed and the sidestand up and down. Also, currently I have 12 volts at the fuel pump relay and it is operating properly. Thanks.

Yes, still have the glass fuses. Ignition fuse tests 12.25V at left and right side wire terminals. R/W wire at relay 10 V not running. At idle, 13.3 V at fuse, 11V at relay. Thanks. I have to go out for a few hours so will reply next asap. Thanks.

I was just able to test while the problem was occurring. When the relay clicks repeatedly and the pump doesn't operate, the voltage at the relay is less than 10. I tested the headlight also, and that is reading 12 volts. After the clicking stops, it also hums/vibrates briefly. I held it in my hand while this was happening so the clicking IS coming from the relay. I tested the relay at the power supply (R/W) and at the fuel pump wire (L/B) and they are both low. So, sometimes, there is insufficient power going to the relay and, consequently, the pump. The starter will work while the problem is happening and, as I said, there is 12 volts going to the headlight. Trying to trace the R/W wire on the schematic, it seems to supply power to the sidestand relay, flashers and some other components and is fed from the ignition fuse. I suck at schematics so if anyone can help there I'd appreciate it. What could cause intermittent decreased voltage going to the relay?

When the problem first happened, I removed the fuel hose at the pump and drained several pints of fuel because I though it was bad gas. So, I don't think fuel supply to the pump is the problem. I have checked the filter and it's good but I'll remove and inspect the petcock and screen. The rapid clicking is definitely coming from the area of the relay, not the pump. I'm familiar with the pump sound as I've owned the bike since 1987. Once the event is over, the pump clicks and the bike runs fine. Thanks for your advice.

When the problem occurs the engine will start and run until it stalls, Then, after a period of time and turning the key, I will hear the pump click and it will run fine, usually until I turn it off although it did stall one time while running. Every other time the problem has occurred at start up. I know the difference between the pump clicking and the relay clicking and, when the problem occurs, it is definitely the relay clicking. I understand the pump will only pump when the carb requires gas and it is continuously powered while the engine is running but will only pump as needed. When it is operating properly, I can see this on my tester. But, I have not been able to test during the problem yet. As I have been testing it all last week, but running the engine and not riding it, I haven't had the problem. It seems to only happen after a ride. Does that mean anything?

Thank you both for the helpful advice. My understanding, please correct if wrong, is the relay is powered by turning the ignition switch which then sends power to the fuel pump for several seconds before turning off. Once the engine starts, the ignitor determines the bike is running and sends a constant signal to the relay to power the pump which is continuously powered until the bike is turned off or the engine is stopped from another system. As I have experienced problems at start and while the engine is running, what is common to both conditions? I understand the relay and pump are, but, is there something else? I don't think the sidestand switch effects the fuel pump nor the "fall over" sensor other than to stop the engine, which, in turn, causes the ignitor to stop the relay from powering the pump. Correct?

I posted last week about a problem with my fuel pump system so I spent a week testing the relay output at start, while running, hot, cold, with the headlight plugged in, with the relay hanging and installed, and no problems. Put it back together and went for a ride yesterday. Today, I went to start it and the problem occurred. The relay clicks rapidly but no power to the pump. By the time I got it opened to test it was working. Now I can't find a relay to buy even though I'm not sure if that's the problem. When the problem happens, the starter cranks and nothing else seems to be affected. I tested the ground at the relay and it was good but I'm not sure where it's grounded to. Can someone tell me? Also, if there is anything else I can test let me know. It's frustrating when I can't test it while it's happening. Thanks.

Thanks for the reply. Fuel filter was replaced recently. Fuel supply to the pump is good so pretty sure the problem is electrical. I know the pump clicks but the rapid clicking was from the area of the relay which made me wonder if it was going bad. I've searched for new replacements but can't find it. If you have the part number that would help. I just checked it again with the meter on it and still working fine. If I can catch a "bad" start I can definitely identify the problem so I'll leave it apart and continue checking it through the week. Thanks.

I have an 87 VR which just hit 50,000 miles. I need some advice. On a recent 900 mile round trip to I experienced fuel supply issues, no fuel getting to the carbs. It would happen after being stopped usually but it happened one time while I was riding after about 60 miles of running fine. With the help of Steve Crossley (thanks Steve) I checked what I could on the road and determined the problem is with the fuel pump system. I was always able to get it running after some time and continue the ride. Now that I'm home, I removed enough parts to get to the fuel pump relay. I've gone through the tests from the manual and the relay, pump and ignitor unit are all testing proper and the bike is running fine for now. I should mention that when the problem was occurring I heard a rapid clicking from behind the dashboard where the relay is located. I also noticed that the relay is only sending power to the pump for about 2 seconds after turning the key on. I've read that it should be 5 seconds. So, what should I do to the relay and wire connector before putting it back together? How do I tighten up the connections inside the plug? Should I clean the plugs with contact cleaner? Is the relay going bad and is there a replacement? I've searched for the relay part, Omron G86-02Y (can't find the Yamaha number and I haven't been able to find it on the parts diagrams) and I can only find a used one on ebay. Are new ones available? It seems the 5 second cut off is what makes finding a replacement difficult. I know it's a safety feature for a stuck float or fuel leak but it seems to me that it's only prevents a problem with the key on and the bike not running in which case I can hear the pump. If the problem occurred while running, there is nothing to stop the pump as far as I know. Thanks for any info you can provide and thanks for the prior help.

I am the original owner. Thanks for the suggestion but that didn't work.

Can you tell me where the cord is located? Thanks.

Maybe it is the microphones. I don't see a way to open the casing to get to the microphones. I'll try to find someone with working headsets. Anyone in Florida with a set? Are any other bikes compatible with our system? Thanks.

Thanks for the advice. When I adjust the volume with the radio off, I can hear a hum through the headsets which gets louder as I adjust it. BTW the CB also works through the earphones. The music will turn off when I adjust the squelch like it should.

Thanks for the advice I wouldn't have thought of that. Unfortunately, the mute buttons are off and do work to mute the radio through the earphones. Good advice though.

Now that all my major problems are fixed with your help, I thought I would try to get my intercom working again. I have an 87 VR with two 20 plus year old J & M headsets. Both headsets ear phones work and music from the radio or cassette works fine. Only the intercom doesn't work. I have tried switching them to the other plug with no help. Because both sets of earphones work, I am assuming it isn't a problem with the headsets but I may be wrong. Anyone have any advice? I have had both top fairing top covers off recently to replace the speakers which work fine also so not sure if I could have dislodged something. Thanks.

Thanks to Freebird's excellent repair instructions and my brother's soldering skills, I am happy to report my controller is working properly. Thanks to all for your help.