hello
i am new and hoping to find some help.
I have a 2510 mule and my fuel pump is only getting about 5.87 volts.
So i go to the relay, mine has 3 wires. With only the blue/black wire disconnected volts are about the same ,the other 2 wires are showing 12 volts.

I am thinking that the blue/black wire is the one that is hot to the fuel pump , and that it should be about 12 volts.Can anyone tell me for sure how to test the relay,thanks in advance for any help.

 

Jamescr I will check in manual 2mrw at shop and get back to you saturday...Thanks.

 

Now 'ats pretty nice right there.

 

Sorry jamescr it got busy at shop an 4got..... Please forgive me man.....I try to remember monday man! im so sorry.......

 

Hey guys, I have a 2510 with the exact same issue as jamescr. Both inputs to the fuel pump relay are 12 volts with the key on, but the output (i.e., to the pump) is 6 volt, even with the engine running. Is the pump a 6 volt unit? There is no label on the pump with a rating.

If I wire the fuel pump directly to the battery, I can run the engine. Will a 6 volt pump run (at least for awhile) with a 12 volt input? If the pump is 12 volt, it's odd that the relay would "fail" and still provide an output of 6 volts.

Normally, I would just swap out the relay and see what happens, but the relay is a $70 part. Don't want to blow $70 if the relay is supposed to output 6 volts. Thanks much.

 

FWIW, someone who knows auto electrical systems told me that measuring the voltage output of the relay with a volt meter connected between the output and ground might not tell the whole story. He said that it might be necessary to connect a working pump to the relay and measure the voltage drop across the pump terminals when the pump is operated.

I had been running the pump direct from the battery, so I knew the pump was operating o.k. So rather than take the time to test the voltage drop, I simply reconnected the pump to the relay. Surprisingly, the pump operated satisfactorily, although the rate of flow at 0 psi (i.e., free flow)was slightly less than when the pump was connected directly to the battery. I bet the pressure is less as well when connected to the relay than when connected directly to the battery, but because I didn't have a pressure gauge, I couldn't check it.

Anyway, the thing runs now, so it seems that my problem isn't a bum relay. However, when I first hooked the pump directly to the battery, it did not run immediately. I had to tap the body of the pump a few times with the handle of my screwdriver to get it to operate. After that though, the pump operated immediately each time I connected it directly to the battery.

This mule was operated for several hours without a fuel filter, so perhaps some debris from the gas tank got into the pump and caused it to not operate intermittently. I have since run the pump for a little while in free flow mode in the hope of flushing out anything that might have been causing it to stick intermittently. The pump is fairly new (replaced just last year) so I'd hate to come out of pocket another $140 if I don't have to. If I run into a fuel starvation problem again though, the pump is the first thing I will replace. For the time being, I'll clean out the carburetor next chance I get to make sure no debris from the gas tank is affecting it either.

 

Ok guys! I have an manual in front of me right now so here we go....first hook 12 volts to pump to see if pumps work... blk\blu to pos. and blk\yell to neg. if pumps works than do next test....relay internal resistance.test lead neg.blk\wht and pos.on blk should be invitinty, and next with neg. leads on blk\wht and pos. leads on blk\blu. is invitinty, and next with neg.leads on blk and pos. leads on blk\wht is invitinty, next with neg. leads on blk and pos. leads on blk\blu is invitinty,next test is neg. on blk and pos.leads on blk\blu is no more than 10 k ohms. if test fail than bad relay, if test good than you hook system up take an test light probe into blk\blue wire at pump and push starter button and it should light up test light when engine is turning over, relay works off the pulse of igniter[ ignion box]. so see if your pump is getting this signal,if pump isn,t getting this signal than blk wire to relay is from igniter see if signal is before relay the same way with engine turn over.... if not than bingo igniter leg to relay not working...Good Luck hopes this helps guys.... sorry so long.....

 

jariddle the pump has breaker points in the tailend under the plastic cap... so when you tapped on pump you could have jarred the points working again, you could try to remove the single screw in rear of pump and try sanding points to see if thats helps....Good Luck....

 

Definitely worth trying before I sink another $140 into replacing a virtually brand new pump.

 

Thanks much. The relay and pump are working again (at least for the time being), but I'll print and keep this in case they act up again.

In the meantime, I am going to try and hunt down a reasonably priced (used perhaps) service manual for this old (but still serviceable) 2510.