Wont Start

[raz]

Do you have a front subframe, hosting the regulator as well as the instruments? Maybe you should check its grounding. That could explain the lot.

[Kiwi_Roy]

The instrument illumination is on another circuit (Fuse 6) with no relay.

No, I'm not talking about the lamps, the drawing definatly shows a connection from 67 of the headlight relay to supply

Generator light

Oil pressure light

Low fuel light

Tacho (not the tacho light)

Headlight Hi/Lo switch

Horn button

Front and back brake light switches.

And to the regulator (what could this be if not a charging reference)

All this is supplied from F5 which appears to be OK because it cranks

If none of the first 7 work I would suspect the relay R2

You could jumper across R1/ R2 direct from the battery to 67 of R2, that will eliminate it. If the lights now go I would check the relay bases.

Another check you can do is unplug R2 and see if yoou get 12V at terminal 30.

Just follow the drawing step by step starting at the fuse F5, R1-30, Put R1 back, R2-30, R2-87 (wrap a short piece of bare wire around the relay terminal so you gan measure it when the fuse is plugged in.

 

I wouldn't suspect the relay at this early stage, you need to take care of the other issues first

 

Kiwi_Roy

[docc]

Sorry, Roy, I misunderstood what you meant by "dash lights." Definitely, the Warning Lights (except for the neutral light) come through Relay 2.

 

I checked my running voltage at 2000 rpm: 13.5vDC. Charging stops when I pull Relay 2 (12.4vDC), so whatever that wire does, it must have voltage from Relay 2 for the regulator to charge.

 

With no horns, headlamps or tach, a problem at Relay 2 would still explain the low charge.

 

All of Raz's and Roy's tests are right on the money, and worth doing. For the simplicity of replacing a relay or repairing its connections, I would certainly try that first, get the lamps on and tach working and recheck the charging voltages.

[Kiwi_Roy]

I checked my running voltage at 2000 rpm: 13.5vDC. Charging stops when I pull Relay 2 (12.4vDC), so whatever that wire does, it must have voltage from Relay 2 for the regulator to charge.

With no horns, headlamps or tach, a problem at Relay 2 would still explain the low charge.

Docc, Thanks for checking that out, I don't have access to my bike at the moment.

I was surprised to see it wired that way, I think it must be to compensate when the headlight is on.

Roy

[Kiwi_Roy]

I have a problem with my charging at the moment, hopefully by the time I get it sorted I will be a whole lot wiser.

Some of the wiring makes me scratch my head, what were they thinking?

[docc]

The two most most mystifying issues for me have been the melting 30 amp regulator fuse and the yellow stator wire that detached itself under the alternator cover.

 

I am preparing to post an FAQ reference on these electrical resources. Yet, I'm waiting for Roy to post "the rest of the story " . . .

[cash1000]

Got bike back from MG dealer.They replaced Rectifier/regulator with an after market one. All go now but its now sometimes not starting due to bad connections in relay block.Any suggestions how to fix?

[lemppari]

Got bike back from MG dealer.They replaced Rectifier/regulator with an after market one. All go now but its now sometimes not starting due to bad connections in relay block.Any suggestions how to fix?

I had the same symptoms in my RM two years back and traced them back to N.o 2 relay and specifically the female connectors underneath. I just bent the middle of the 'spade' inward with a small screwdriver and voilá, no problems with the electrics ever since. (Knocks his head..er..wood)

[Kiwi_Roy]

Got bike back from MG dealer.They replaced Rectifier/regulator with an after market one. All go now but its now sometimes not starting due to bad connections in relay block.Any suggestions how to fix?

Here's how to get the f/m connectors out of the base, I need to fix some of mine as well

The larger ones are quite easy to find in automotive store, they are a universal style, the smaller ones are universal also but harder to find.

You will probably get by just squeezing them a bit. I use petroleum jelly on mine to keep air and water from corroding.

Relays Bases April 24 2010.pdf

[Kiwi_Roy]

The two most most mystifying issues for me have been the melting 30 amp regulator fuse and the yellow stator wire that detached itself under the alternator cover.

 

I am preparing to post an FAQ reference on these electrical resources. Yet, I'm waiting for Roy to post "the rest of the story " . . .

I assume the yellow wire is soldered to the coils, in that case it was likely an electrical overload heating up the wire to a point where the solder melted.

There are two reasons why the fuse would melt, over current or a combination of high current and a loose fuse clip.

I found mine not blown but welded in place and hot to touch. After I squeezed in the clip a bit it has no longer overheated. If the clips are tight it shouldn't get hot before blowing as the fuse link is quite small relative to the contact pins. Of course it will get warm.

Roy

[docc]

Well, the yellow stator wire was broken inside the alternator cover, but had not "de-soldered." It was, however, hard to see and find.

 

No doubt the very small clips (female connectors) in the fuse block are hard pressed to handle the 25+ amps of charging. They only make about 25% contact with the ATC fuse blades (when they're in good shape!).

 

Replacing the charging (regulator) fuse (#3) with a MAXI fuse will be part of the solution.

 

Ah, if only, The Answer were just one thing!

[Kiwi_Roy]

Well, the yellow stator wire was broken inside the alternator cover, but had not "de-soldered." It was, however, hard to see and find.

 

No doubt the very small clips (female connectors) in the fuse block are hard pressed to handle the 25+ amps of charging. They only make about 25% contact with the ATC fuse blades (when they're in good shape!).

 

Replacing the charging (regulator) fuse (#3) with a MAXI fuse will be part of the solution.

 

Ah, if only, The Answer were just one thing!

I wonder if you could jamb some rubber material like part of an "O" ring between the case and outside of fuse clip to give some added tension

[docc]

I wonder if you could jamb some rubber material like part of an "O" ring between the case and outside of fuse clip to give some added tension

I think it is more of a surface area issue. The blades of the ATC fuse are already small, but the clips only grasp about 25% of the blade. What prompted me to change them was the opinion of one the board members (I'd have to go back and look to give proper credit) was the heat cycling will have surely destroyed the tensile strength of the metal. To reiterate, though, I tried an external ATC fuse holder whoch also melted the fuse or burned off the blade.

So far, the MAXI fuse has been 100%.

[lemppari]

After stopping and killing the engine I suddenly remembered I had forgotten to run an errand and switched on again. Follows the familiar priming of the pump sound, follows pressing the start button. Follows....nothing. Not even a click from starter relay. Pull the clutch and push the button.....silence. Pull the bike upright, sidestand in, clutch in....nothing.

 

Switch off and on again a couple of times and basta. The RM starts WITH the sidestand DOWN, clutch pulled.

 

OK, first things first, I'll check the relay base once again, but what then? Incidentally, I didn't have such problems before my moose bang, because the previous owner had dismantled the sidestand switch as well as the clutch microswitch. When rebuilt by the importer's service, they put all the stuff back on. Upside is all new electrics, downside, well....silence.

 

But at least I got the speedo working again.

[Kiwi_Roy]

After stopping and killing the engine I suddenly remembered I had forgotten to run an errand and switched on again. Follows the familiar priming of the pump sound, follows pressing the start button. Follows....nothing. Not even a click from starter relay. Pull the clutch and push the button.....silence. Pull the bike upright, sidestand in, clutch in....nothing.

 

Switch off and on again a couple of times and basta. The RM starts WITH the sidestand DOWN, clutch pulled.

 

OK, first things first, I'll check the relay base once again, but what then? Incidentally, I didn't have such problems before my moose bang, because the previous owner had dismantled the sidestand switch as well as the clutch microswitch. When rebuilt by the importer's service, they put all the stuff back on. Upside is all new electrics, downside, well....silence.

 

But at least I got the speedo working again.

Sounds like R1 not pulling in because of an interlock open

Try putting the bike in NEUTRAL remove R1 and jumper the two large pins by poking a wire in the socket, that bypasses the interlocks and tries to pull the starter solenoid in. If that works look for a fault in R1 coil circuit.

If it doesnt work it's on the contact side.

 

 

http://www.v11lemans.com/forums/index.php?showtopic=15718

One of the contacts in my relay base for R1 wasn't gripping the relay pin at all.

Roy