Start circuit problem related to cut-off / turn signal relay

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Akatora

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Hello again,

After having most starting and ignition related sockets apart (for getting the pins checked and treated with corrosion prevent spray) there occurred two very interesting problems. The problems were not so special, but the solution (same for both problems!) sounds almost like healing by holy smoke...
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Problem 1- starter did not work.
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All the electricity was available and when pressing the start button, no effect other than the oil level warning light and the headlight disappeared just to return when the start button was released.

Checked the starter motor by shortly connecting the battery cable into the starter motor cable. Motor was proved fine. Then checked the starter relay action by having the battery lead in place and connecting the blue/white wire to the ground. Result was ok (provided "click"). Proceeded into checking the start button switch operation by measuring the continuity inside the switch (blue/white - black), also ok. Then checked the continuity between the blue/white wire inside the start button switch and the other end of the same wire (located in the pin 9 of the starter circuit cut-off relay/turn signal relay socket). Result ok. Then checked the continuity between the blue/white wire in the pin 8 of the same socket and the other end of the same wire (located under the saddle, where it is going into the starter relay). Continuity was ok. Therefore the only possible cause was the starter circuit cut-off realy itself.

Now the solution... Took the multimeter, set it to the 2M ohm scale and connected it between the both blue/white wires (pins 9 and 8) in this cut-off relay. Then switched the ignition on and pressed the start button in order to see whether the relay created contact between these two wires that have to make full circuit until the starter relay. Well, the action of the starter returned during this measurement. It also stayed good afterwards.

Now we had the starter back in life - but the engine did not start, no matter how much let the starter to turn. This is not normal, as the Max should start easily IF the starter works. So... after slightly opening the fuel draining screws on each carburettor and confirming that fuel reached all the carbs...

Problem 2 - no spark in any cylinder.
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I had perfect voltage coming through all of the ignition HT coils' primary side. Therefore no reason to suspect the pick-up coils (which were by the way just renewed a while ago). Checked also the fuse for safety's sake. It was ok. In this case, the only suspect was the TCI unit or it's connections - especially because there were NO SPARK IN ANY OF THE CYLINDERS. Then considering the previous problem with the relay that has similar kind of connection socket...

- the natural solution: Yes, applying the same method I first measured the continuity between the red/white (power) wire in the TCI socket and the frame ground (ignition switched into OFF position). There was continuity. Then measured the continuity same way between the black (ground) wire in that socket and the frame ground to make sure... Also existed continuity. Then switched the power ON and measured the voltage from the red/white wire in this TCI connection socket. It showed about 10,5 volts or something like that. Immediately after that pushed the start button to see whether the sparks were back - and yes they were!
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Conclusion:

It seems that rust preventive spray (I used CRC) can create problems like this. Note that when reading the measurements with the multimeter I did not unplug the sockets anymore - or make any kind of mechanical adjustment, just let the multimeter to pass small test current through them. Sounds like fixing the problem using flashlight, but as it fixed two similar kind of problems (that both developed themselves during the treatment - they worked before) it seems however reasonable. Considering that the CRC spray maybe creates a very thin coating there it could be possible. But the problem was noticed only in these two cases. I checked the turning signals and they were ok. This could be related into the amount of current passing through. If the current is bigger, it just rushes through small preventive things like the coating. But smaller currents might not be able to do the same.
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I think this theory can now be confirmed after following happened:

I had carbs off and fuel pump disconnected for some v-boost movement range and jetting adjustment. Max worked perfectly normally before disassembly (except the need for setting). After putting the parts back - however - it did not turn the starter motor. For safety's sake, even if I was almost sure about the problem, I just connected the starter relay "wake-up wire" to the ground via jumper wire. Starter worked normally, but after this test the start button did not cause action.

Then connected jumper wire between the previously mentioned two blue/white wires in the cut-off relay and pushed start button. Fired up immediately. After taking the jumper wire away and trying to start the engine normally from the button it was fine. So good idea to include some jumper wires into the tool bag. Small thing, big action.

Further, I do not believe that the relay is actually bad as it works ok if no special action is taken. For some reason it seems that it "falls into sleep", but now I got the waky-wake means...

Previously I suspected the corrosion prevent spray to be the root cause, but this might not be the case.
 
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