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Discussion Starter #1
A neighbor bought a 1984 VT700 Saturday. He does not have anywhere to work on the bike, so it is in my shop now. With the bike on the center stand and in high gear, I can turn the motor and feel it come up on compression like it should. The bike sat for over two years with the dead T-battery in it. This positive cable must be replaced.

The former owner had removed the fuel pump and by-passed it breaking the pump inlet in the process. The filter is missing from the air cleaner. The bike came with the broken fuel pump and a new shop manual.

There is a 30 amp fuse on the left side by the battery that is blown. What would cause this fuse to blow? Is it common for the fuse to blow on this model bike? Will the starter crank the motor without this fuse? I’m thinkin’ the fuse may be the reason the bike would not start for the former owner.

Thanks
 

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Assuming no one has messed with the wiring then the 30 amp fuse supplies all the power to the bike except the starter motor (starter motor is fed through the starting relay direct from the battery). From the fuse one wire (red) goes to the ignition switch, the other (red/white) goes to the regulator/rectifier. Could be the corroded positive cable created enough current to blow the 30amp fuse. It would take a pretty heavy short to take out that fuse, possibly a shorted R/R.
 

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Discussion Starter #3
We worked on the 700 today. When I drained the old stinky gasoline out, it had about one tablespoon of water. We now have the new battery cable, fuel filter, fuel pump, new fuel hoses in and out of the pump, new 30 amp fuse, new gasoline, new air filter, and the battery from my Shadow.

The problem now is that the fuel pump will not run. I checked with my old analog voltmeter, the black/blue showed 12 volts. With the voltmeter between the green wire and the battery, it showed 12 volts indicating continuity. Hot wired the new fuel pump and it ran fine.

I got the idea to check with a test light also. The test light is one of those little lights inside a screwdriver like handle with the point on the end. It’s a very small light and should not take much current to light it up. The black/blue still showed 12 volts, but would not light up the test light. I encountered something like this on my John Deere combine many years ago and finally found a corroded connection. Showed voltage, but would not carry any current.

The Clymer manual does a poor job of covering the electrical stuff, like fuses and relays. All it says about the fan fuse is that there is an inline fuse, it does not say where. The fan turns on with the key and we wanted to pull the fuse to shut off the fan.

I’m thinkin’ there may be a problem with the fuel pump relay, but I have no idea where it is and I don’t want to start taking the wrap off the wiring harness.

Can anyone tell me where the fuel pump relay is located on this VT700?

Someone told me that there may be a safety feature that will shut off the fuel pump if the bike goes down. Anyone know anything about that?

A hillbilly friend stopped in for a while and suggested that I wire the fuel pump directly from the taillight circuit. I’m going to have to think about that for a while.
 

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The fuel pump will only run when the engine is running. Voltage from the spark unit is what activates the fuel cutoff relay supplying power to the pump (that's why the pump runs when you jumper it from the battery). As for the fan the thermo switch at the bottom of the rad is probably shorted. Just pull the two pole plug off the switch or unplug the fan until you can get the switch replaced. 'Course if you get it running keep an eye on the temperature.

Dave
 

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Discussion Starter #5
Dave,
Thanks for your help.

I still have a problem getting the fuel pump to run. My neighbor called me and wanted to tinker with the bike again. It was very cold in my shop, but at least it was out of the 40 mph wind.

I hot wired the fuel pump until gas ran out of the drains. Closed the drains and ran the pump to fill the carbs. The bike was reluctant, but it started and ran like it hadn’t run in three years. The longer it ran, the better it sounded. Then after it ran about two minutes it died, so I unplugged the fuel pump and hot wired it again to fill the carbs. It started and ran for about two minutes then died. By this time the motor was getting warmed up and started good when it had gas. I put the test light in the blue/black connector to the fuel pump with the motor running and showed no power to the fuel pump.

We unplugged the fan switch; the fan still will not shut off when the key is on. I’m thinkin’ that either the fan relay is stuck on, or the original owner bypassed the relay, but if that is the case, I have no idea where. I still don’t know where the fan fuse and the fan relay is.

He got a phone call and had to jump in his truck to take a load to Indiana, so we will tinker some more next week. Before he left, he said he will get a fuel pump relay. He did not want to bypass the fuel pump relay after we discussed the hazards of doing that.

Al
 

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Al,
There is no relay for the fan.

As per the diagram 12volts is supplied from the 10 amp fuse to the fan motor and the thermo switch connects to ground running the fan. With the ignition switch off unplug the thermo switch and test the plug for continuity. Maybe someone has shorted the blue and green together ahead of the plug.
Looks like you'll have it running with a new cutout relay. Congratulations!

Dave
 

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That 10 amp fan fuse is "conveniently" located within the nest of wires in the headlight bucket. The Clymer manual is indeed sketchy when it comes to the electrical system. Good luck in resurrecting that vintage Shadow.
 

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Everyone seems to be giving good advice, so I won't comment on that. I will say that the most common "screwdriver" type test lamps have a neon bulb in them, not a standard light bulb. A neon lamp won't light at anything below 70 volts, so no matter what you do on your bike, it won't light. Even if you hook up to the battery, you won't get anything from it. They are handy for checking ignition though, since 20,000 volts is much higher than 70! :wink:

Anyway, keep tinkering, and keep us posted!

--Justin
 

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Discussion Starter #9
Thanks for the location of the fan fuse. We will try taking the fuse out and trace the wiring from there.

The test light I was using is for low voltage, it has a handle like a screwdriver, a wire with a clip, and a point like an ice pick. I know what you mean about the neon type, I have one around somewhere.

After we got the new fuel pump relay in, the bike started and stayed running. While it was warming up, I slide the fork wipers up and cleaned up all the oil I could. Fork seals will be later. I took it for a short ride. It runs a little rough and some fork oil may have gotten on the front brake.

I told Dave about someone who bought a 700 or 750 Shadow that had been sitting several years. We rode about six hours to the horse races in Omaha, his Shadow ran rough and got less gas mileage than my 1100 Shadow on the way to Omaha, but by the time we got back to Kansas, his Shadow was getting better gas mileage and was running much better. So, I told Dave I think we should put a few hundred miles on it and see if the same thing happens.

Now for the part I really don’t want to tell you about… But I will because it may help someone else and you can’t see the sheepish look on my face.
When we put the plastic radiator cover back on, I screwed the screw into the bottom radiator tank. Now that must be fixed also. Taking the radiator off to get the hole soldered will not be a total waste of time, the outside of the radiator could use a good cleaning. The former owner lived on a gravel road and sometimes rode in the mud. I blew out a bunch of dirt already.

The bike still needs some TLC, but should make a great bike for him. Dave is a fairly small person so the bike fits him well, the 700 is all the bike he needs. Last year, Dave was in Atlanta tarping the load on his truck and some idiot in a pickup ran over him. He still has SS screws and plates in his right foot and leg, so he can not even think about putting his bike on the centerstand. Hey, that’s what neighbors are for.
 
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