No crank, no click

If the thermoswitch is a 2-wire, connect the wires with the key on to test the fan. If a 1-wire, ground it with the key on.

Here is something I recently typed up to install a toggle and preserve original functionality:

I believe the 1000R Thermoswitch is a 2 wire, so you complete the circuit to turn on fan. Each lead going to the switch needs to be split into two leads, one continuing on like stock, and one going to the toggle. I usually try and preserve original wiring using OEM style connectors and then splitting after, but the cap-style connector for the thermoswitch makes it hard. You will likely have to cut the harness before the plug.

If a Thermoswitch is 1 wire, then you ground the wire to turn on fan. So split and one continues on as stock, and one goes to the toggle. The other side of the toggle goes to ground. On a one wire system, there is a way to use a on-off-on toggle without cutting anything. One "ON" to let the Thermoswitch control when to kick on, and the other "ON" to turn the fan on manually.

Use the same 2 wire principle to install a parallel toggle for the Fuel Cut Relay also. It is a potential life saver out on the road and makes priming the fuel system after storage a breeze, without having to crank forever.

 

Thanks! I'm about 90% sure it's a 1 wire from what I remember, so that makes things very easy on that front.

The charging system is what's been giving me nightmares. I should just trailer it to my house instead of having to drive 15 minutes one way to my dad's every time I want to work on it. I really need a bigger garage lol

 

^ everyone needs a bigger garage.

test stator with r/r unplugged. measure AC volts between each combination of yellow wires at idle and at 5k rpm. at idle expect 8-10 volts and at 5k it should be about 55-60 volts. if stator checks ok and you have low charging then it's a bad r/r.

bikes don't like idling for long periods, and you should have probably have shut it down earlier to avoid overheating. fan switches often fail on older bikes.

 

Yeah I should have shut it down sooner, but I wasn't sure what to expect. Where on the gauge should the fan normally kick on?

 

fan should kick on at about 2/3 of the scale.

 

You really need to follow the drill to check the stator.

To TEST the fan just run an earth to the neg side.
Almost put money on it will run...

When the temp sensor reaches X it switches to allow the earth to pass which then turns the fan on (as it has power at all times)

If you don't ensure that their is zero air in the system first then you may get erratic results on the thermo switch.

 

Good news (mostly) and bad news...

Both the stator and R/R test good. At the stator I'm getting 0.5-0.7 ohms on all wire pairs. While running I'm getting consistent voltages across all pairs, 20v at idle and 70v at 5k RPM. All the diodes test good on the R/R. The weird thing is, not much has changed at the battery. I finally installed the new wire harness for the starter solenoid which I'm sure helped things a little. I'm now getting 13.1v at idle and 12.9v at 5k RPM. Is this normal? The electrosport flow chart says it should be above 13.5v at idle and lower than 14.8 at 5k RPM. BTW all the links I found for the flow chart here seem to be dead. It now lives at https://cdn.shopify.com/s/files/1/1091/5694/files/fault-finding-diagram.pdf?235929069374954073

I think the cooling system is fine. When I was looking at the fuses I thought there was only 1 fuse on the left side and all the other slots were labeled spare. Well, they weren't all spares and the one I took for the starting fuse was for...the fan. I put a 30a in temporarily and was able to get the fan to turn on by grounding the connector that goes to the temp sensor. I was unable to test if the fan actually comes on by itself because....

This bike was a firebomb waiting to happen. The gas tank is apparently leaking at the bottom where some random bare wire is soldered directly in to the tank (see pictures). The heat shield on the under side of the tank was completely drenched in gas and it ran down the side on to the exhaust pipes while it was sitting the last couple days. When I started it up today I saw the pipes has some smoke coming off them and assumed it was oil from just oiling the chain and taking it for a test ride the other day. After I was testing the stator and gas dripped on my hand I found out real quick what it was and that ended the running tests. I don't understand what the wire going in to the gas tank is for...it makes no sense to me. There is no fuel level sensor on the bike. The connector on the other end of the wire was plugged in to the wire ahrness under the seat. It looks like this has leaked before because there was some semi soft goop all around the wire. You can still kind of see it a little. So what do I do to fix this? As long as the charging system is ok and the fan comes on I think the gas tank is the last of my issues.

 

HOLT SHIT! WTF?! Wow, that's some fucked up home engineering right there.

I suppose you could have a plate properly welded and then seal the bottom of the tank also. Good tanks are hard to find. Well... reasonably priced tanks, that is.

 

there is a fuel level sensor which turns on a red light when fuel is low.

 

Where is the low fuel light? I must have missed it somewhere. I thought there was only the reserve switch on the 86?

So what is that wire? Can I just remove it and weld the hole shut? I can't see any scenario where a wire going in to the bottom of a gas tank would ever be liquid tight.

 

on an '86 VFR 700 that light is on the panel with turn and neutral lights iddin it ? and the sensor is mounted above a rectangular plate about 3" across.

look at the wiring diagram to find the wire from the sensor illustrated, and check the fsm on page 20-6 for more info clearly showing the fuel sensor location. somebody fucked with your tank b4 you bought it.

 

Those voltages look very bad to me....
70v will screw everything on your bike....

Bear in mind they probably removed the fuse due to your wiring being screwed due to the voltage issue.

Good catch - always better to find this before needing the fire brigade...

 

It's possible I'm completely blind. I looked at the lights and thought for sure there was none that said fuel. This pic says otherwise https://i.ebayimg.com/images/g/AokAAOSwFiZeuVfn/s-l640.jpg I'll look when I'm down there again in case it's not the stock unit but everything else looks correct.

I found a pic of a sensor https://cdn.shopify.com/s/files/1/0709/8407/products/5704_large_2x.jpg?v=1470611779 I'm hoping that there are bolts under that putty stuff and I can just get a whole new sensor.

Someone can correct me if I'm wrong, but I think that's normal. The R/R should bring that down to the correct DC voltage.

That was just me being an idiot and not reading lol

 

are these the voltages before the RR ?

If so, then what's the voltages after?

What are the voltages at your battery - 20v at idle will fry it, 70v at 5000rpm will destroy it.

This is why so many people put a volt meter in the system of the older bikes.

 

Yes, that is the voltage coming out of the stator.

I actually didn't think to disconnect and check what was coming out of the R/R but I was getting 13.1v at idle and 12.9v at 5k RPM on the battery terminals.

After looking online a bit I bet that mess I peeled off was JB Weld putty. I'll see if I can get the rest of it off to get a better idea of what is actually going on there and if it doesn't look like I can get a new gas level sensor I guess my only option is to go back to JB weld or get it actually welded.

 

If you can get back down to the mount studs and a clean seat for the o-ring, just get a used sending unit. Even if the sensor doesn't still work, with a new o-ring it will be the best long term solution.

Some HACK probably starting gooping JB-Weld when the o-ring failed or the soldered rivet on the sending unit starting weeping from corrosion.

 

12.9V at the battery @ 5K is too low. You should be seeing high 13s to low 14s.

 

thought that also depends on where you take the reading from?

 

At the battery. Eventually numbers like that will leave you flat.