Starter Relay problem

[jdm9123]

Hi guys. Something weird is happening with my bike. I thought my relay was bad because I wasn't getting battery voltage to the tower that connects right to the starter so I bought a new one. The same thing is now happening with this relay. What I do know is I am getting battery voltage to the first tower on the relay. I have power at the starter switch and if i cross the towers with a screwdriver the starter motor spins over. Also, one of the fuses gets hot when I turn the ignition switch on. Could this tie into the engine stop switch? It just seems like the relay isn't transferring the power after its magnetized and I don't know why. Thanks in advance.

 

[retiredgentleman]

The starter relay has 2 small wires on its operating coil. When you turn the key on, you should measure battery + voltage at the red/white wire terminal. The other wire, blue/white, needs to have a ground from the start push button. You can test this by using a spare piece of wire as a jumper wire, and connecting the blue/white to a good ground or to battery -ground terminal.

The start push button gets its ground from the handlebars. Check with an ohmmeter to see if the handlebars are in fact grounded.

If your bike has points, there is the possibility that one set of points is closed. With the key on and if the kill switch is in the "run" position, then there will be current flow to one ign coil. This can cause a fuse to heat up, as well as heating the ign coil. Don't leave the ignition switch on unless the engine is running, or if you do, then select the kill switch to off.

If you still have the original 4 position fuse holders (glass fuses), they are worn out and can cause the fuse holder/fuse to heat up due to high resistance. Replace with blade type fuse holders.

 

[MaxPete]

This is an old thread I know - but yup, I've got exactly the same issue in August of 2016 with my '76. At one point I discovered that the handlebar was not grounded very well, but I though I had fixed that issue. I then changed the solenoid to a known good one and wah-la - it worked perfectly for a couple of days - until this morning when it refused again. I am getting tired of bashing the inside of my right knee on that squarish corner of the RH side cover.
I guess I'll go back to the ground for the handlebar and check it again. Dang! This thing seems to be haunted.

 

[retiredgentleman]

With starter motor problems, the first thing to check is the battery. How old is your battery? Does it normally hold a charge or do you have to sometimes use an external charger?
Here's a simple test. Fully charge your battery with a bench charger. Connect your digital VOM to the battery terminals, to read voltage (20 volt scale) . Now push the start button (key on) and watch the battery voltage at the same time. The voltage should stay at 10 volts or greater as it attempts to crank the engine. If you see a quick drop to 9 volts or less, chances are your battery is worn out.

 

[MaxPete]

Thanks Gent : but the battery is new this year and holds a charge just fine. It also does fine on a load test.

Nope, it is either the handlebar ground - OR - this thing is haunted.

 

[retiredgentleman]

Thanks Gent : but the battery is new this year and holds a charge just fine. It also does fine on a load test.

Nope, it is either the handlebar ground - OR - this thing is haunted.

It should be simple to do a few tests. I see 3 possibilities. No ground coming from the starter push button, or no + 12 volts coming from the Safety Relay, or the starter relay (solenoid) itself is defective. .
If no ground comes from the push button, either the button itself is failing or no proper ground connection to the handlebars.

I would put a temporary jumper wire on the blue/white wire terminal and ground it to the battery negative terminal.Then turn on the key to see if it works. Test the other way by connecting the red/white terminal to battery positive terminal and then using the push button.

 

[MaxPete]

OK - I think I've got it. The handlebar ground is intermittent and so I have taken quite a few steps to improve it and NOW the danged starter seems to work everytime....until the next time it chooses to not work. Then, I'll be back to bashing my right inner thigh on the side cover. Thanks so much to everyone who wrote and offered suggestions.

Hmmmm.

 

[MaxPete]

Well, another frustrating day. Just as I thought that the issue was handlebar grounding, it turned out that it wasn't. I went on a ride with some buddies and the starter failed to work after a fuel stop. Of course, it should have been obvious that the handlebar was properly grounded because the horn works perfectly and it also uses the handlebar as a ground. If the handlebar ground was bad - the horn wouldn't work, along with the starter.

Nope...that wasn't the problem.

It turns out (I'm 97% sure) that the problem all along was the starter safety relay (SSR) That's the little domed boxy thingy inside the RH side cover just under the starter solenoid. It has a R-W wire and a 3-terminal plug coming,out of it. The SSR is there to prevent you from engaging the starter motor while the bike is running - thus, it protects that fragile and expensive starter gears. It does this by preventing 12 volts from getting to the primary windings of the starter solenoid IF the bike is running and the alternator voltage is above about 6 volts or so.

After much though all day about what the he!! is going on with this starter circuit I finally pulled off the SSR (two large JIS screws), disconnected the R-W wire and the 3-terminal plug and took off the domed cover (two small JIS screws). Wow - what a mess inside! The innards of this thing were corroded and dirty and there was a layer of mung on the little contacts of the armature. Once I cleaned it up with some electrical cntact cleaner and a toothbrush, the darned thing worked perfectly.

BTW - there are all sorts of postings on the web about ditching the SSR and running without it - but I wouldn't do that. If you eliminate the Starter Safety Relay and then accidentally hit that starter button while tooling down the road, you could do A LOT of damage to the starter gear train and possibly wind up with metal debris floating around in the crank bearings etc.

Anyhow, I think I've got it - but the proof will come over the next few days if that danged starter keeps on working.

Cheers and again, thanks so much for all the helpful suggestions and advice.

Pete

 

[Wingedwheel]

I don't know about your starter problem Pete but I can offer a suggestion to remedy the haunted part. A Guardian Bell works great for keeping those pesky little road Gremlins that you can pick up while riding off your bike. LOL.

 

[TwoManyXS1Bs]

Do they do the Guardian Bell thing in GB?

 

[retiredgentleman]

Yes, the Safety Relay corrosion sure could cause problems......................good detective work!

 

[MaxPete]

Thanks! I sure have learned a lot through all of this - but as mentioned earlier, the REAL proof will be whether the darned thing keeps on working.

Cheers,

Pete

 

[MaxPete]

Hi All:

Well, its now been just under two weeks and the starter has not yet failed to crank the bike, so...it does appear that the Starter Safety Relay was the problem. In conclusion, if your starter button makes the oil pressure light come on - BUT - it doesn't commence any action from the starter motor - AND - you have a good battery and good ground connection on the handlebars, try the following 15 minute job:

1. remove RH side cover and the two large JIS (looks like Philips) screws which attach the Starter Safety Relay (SSR) to the frame of the bike;
2. remove the electrical connectors so that you can take the SSR to the workbench;
   
3. remove the very small JIS screws that secure the relay cover to the base (these little guys are really small - don't drop them!);
4. GENTLY clean everything you see inside the relay cover with electrical contact cleaner and a toothbrush (including passing a business card between the two relay contacts to clean off any crud in there);
5. reassemble and see if things work better.

Once again, I would not eliminate the SSR, as others may suggest. The relay prevents the starter from being accidentally engaged while the engine is running and so it protects the complex, expensive and difficult to repair starter gears from being ground to a pulp. The relay is a simple device and it should be reliable - but after 40-odd years, it may simply need to be cleaned - mine sure did. Also, you can check the handlebar ground connection by simply checking to see if the horn works. If you get a good loud "beep" - you've got a good handlebar ground.

NOTE: this Starter Safety Relay problem is not related to the well-known XS650 Bendix drive gear issue - if you've got that problem and you hear a horrible grinding sound when you hit the button, you will need to do an entirely different repair involving removing the RH engine case (clutch cover) and replacing the final drive gear and spring clip. There is tons of info and several videos on how to do that job.

Pete

 

[glennpm]

Hi,

Hoping to get some wiring help with a non-stock setup.

I have trouble starting my bike when warm and decided to put my starter back into service on my presently kick only setup on my 79 XS650 . I have the starter installed now and have been looking at the stock wiring diagrams and do want to use the Starter Safety Relay, SSR. The yellow wire is what I'm not sure about since I have a PMA and not the original alternator.

Is it safe to use any of the PMA output wires to the regulator? The reason I ask is that I've seen mention that to test the SSR is to not apply anything over 6V. I could reduce the voltage source for the SSR is I used the output from my regulator but then I would need a diode and tap the yellow wire between it and the regulator otherwise I would always have 12V battery voltage.

"
Safety Relay Operation
Copyright 2001 Ken Maxwell

The purpose of the safety relay is to isolate the starter circuitry once the motor is running to prevent starter gear grinding. On the early model 650's there is only the safety relay located under the right side cover just under the starter solenoid. This type controls only the starter circuitry and has nothing to do with the head light circuitry. On later model 650's (79 up) there are actually two relays. A Safety Relay (SR) that controls power to the starter, and a lighting relay (LR) that controls power to the headlight and lighting system. They can be identified by their distinct two humps.

When the ignition switch is turned on, current flows through the safety relay's normally closed relay contact to the starter solenoid. Current is stopped at the LR by it's normally open contact. When the engine is started, voltage produced by the alternator sends current through the SR, LR coils. The relays turn on and their contacts change state. The SR contact is now open and breaks the circuit to the starter solenoid. This prevents the starter from accidentally being engaged while the motor is running. Note that the SR's operating voltage is rated ONLY about 4-6 volts. You can burn it up with 12 volts. Use 6 volts (battery charger) when testing. The LR contact is now closed and feeds voltage to the headlight and instrument lights by way of the reserve lighting module"

Appreciate help with this.
Glenn

View attachment 161412 View attachment 161414

 

[glennpm]

I believe I found confirmation that I can splice into any of the three yellow PMA wires.

http://www.xs650.com/threads/safety-relay-yellow-wire.22578/

Glenn