Thursday, August 1, 2013

Electric Starter System Troubleshooting Part 1: Learning How to Drain Engine Oil Among Other Things

I've been reading through the manual to troubleshoot why the starter switch might be causing the relay to go nuts. The ZX600RC1 manual referred to a Base Manual for going through the starter motor removal in detail (which thankfully was updated on this forum 12 days ago).

After reading through the base manual, I found some possible scenarios which may be causing the symptoms it's having. A winding on the starter motor might be open (having infinite resistance) which would make it very difficult for the current to make the starter motor turn. Also, if there's a short between the commutator and the shaft, that would indicate that the armature has a short and would cause weird things to happen to the starter circuit relay. (The starter circuit relay is different than the starter relay, because it's behind the starter lockout switch. The starter lockout switch ensures that the vehicle is in neutral and the clutch is engaged - the clutch handle is out - in order to prevent the bike from being started in gear. The starter relay is what directly controls current to the starter motor).

This picture will help explain:

The recommended fix for these problems is replacing the whole starter motor (mostly because if these problems occur, the motor is old and should be replaced anyway). Dash said he has the same bike sitting in his yard, and offered to scrounge it's starter motor. Hopefully that's the problem and I can replace the starter motor with Dash's motor.

Now that it's 1:25 AM (morning of July 31, 2013), it would be ridiculous to remove the motor tonight. I will tackle this problem tomorrow.


First I tested the relay with a multimeter before ripping apart the starter motor.

Starter Relay
I disconnected the big battery and motor leads from the relay.

As instructed by the base manual, I measured the resistance across the battery and motor leads with them disconnected. If the relay clicked and the multimeter read 0 ohms, then it would be in good shape. However, the relay didn't click at all, and it didn't read 0 ohms. I got approximately 1 Mega ohm until I realized that was the electrical resistance of my body (from left hand to right hand). So, no resistance reading and no click; the manual says the relay is dead. It may be right it's probably right, but I still think the starter motor is at fault. I'll try another test that bypasses the relay to isolate the starter motor.

Conclusion, starter relay most likely needs replacing.

The relay is there to make all the switches regulate when the starter motor gets current. So I just bypassed the relay and all the logic with the Engine Stop Switch, Ignition Switch, Neutral Switch, and the Starter button. To bypass the relay, I just shorted the Battery lead (B) and the Motor lead (M) together. This should supply current to the starter motor and make it spin; there shouldn't be any sparks because it's basically just wiring up a motor to a battery.

The result: The battery and motor leads sparked when I first touched them. This makes me think the starter motor is shorting inside itself somewhere which would cause such a big spark where it shouldn't have.

The black smudge on the right nut resulted from the spark (basically shorting a 12V lead acid battery).

After shorting them for more than a split second the starter motor sounded as if it were trying to turn but couldn't. It is definitely shorting somewhere inside the motor, but maybe only on one winding (which would explain why it sometimes makes the relay unhappy and sometimes spins). The problem may be a combination of both the starter motor and the relay. But this test confirms that I need to disassemble the starter motor and see what's inside. Time to get a little messy.

The starter motor is hidden behind an oil line and a coolant hose. I wonder why they designed it this way!? It sure would've been nice to be able to remove the starter motor without draining the coolant system and engine oil.

Oh, the engine is full of oil, and if I removed the starter motor, all the oil would drain out the starter motor hole. But why the coolant system? Maybe it needs to be replenished more often than fixing the starter motor. So, if the starter motor breaks, then it's probably a good time to cycle the coolant system. Maybe it's a good design after all...

Draining engine oil: It's pretty simple actually. Unscrew the engine oil drain plug and drain it into a pan. Finding a grungy pan was the hardest part. This instructable explains how to drain oil from a motorcycle engine. Important note: If the engine is hot (i.e. the oil is also hot), then the oil drains much better than if it were cold. So, run the engine for a little while before draining the oil.

Ever wonder what oil labels like 10W40, 10W50, or 20W40 mean? The different numbers basically indicate how viscous the oil is and how "pumpable" it is at certain temperatures. Certain systems require different types of oil (e.g. smaller engines that have smaller hoses would need a less viscous oil to ensure that it flows well).

Draining the Coolant System: Note to self... Make sure to check the coolant from the reservoir tank and not the radiator cap. The radiator cap opens up the air tight coolant system and lets air in. Therefore, by simply opening the radiator cap you're dooming yourself to bleeding the coolant system of air. Air in the coolant system isn't super bad, but it lowers the efficiency of your cooling system and its ability to take heat away from the engine.

The coolant is NOT just water. It's about a 50/50 mix with a green liquid called ethylene glycol. It's basically the sweet pink antifreeze that you would put in the water system of a motor-home to keep the pipes from freezing in the winter - hence "antifreeze".

Unlike draining engine oil, it's best to drain the coolant long after the engine has run when it's at room temperature.

Ran over to the Sunoco gas station near MITERS
Coolant is a mixture of water and ethylene glycol antifreeze; there aren't any variations like with oil. So anything with ethylene glycol in it works fine. However, one thing to keep in mind, motorcycle coolant is not the same thing as coolant used in cars! So don't even think about using the same stuff for both vehicles. You can buy stuff premixed, but your half of what your paying for is slightly overpriced water. You could also mix it yourself, but be sure to use distilled water. The minerals and ions in tap water can cause corrosion to internal engine components, which isn't very good. I'm sure you can use tap water (as some people do and their engines run "fine") but it limits the life of the engine and may will cause more problems in the long run.

Over the weekend, I'm traveling up to Wilkes-Barre, Pennsylvania to pick up the Kawasaki KLR650 that my Dad rode down when I was heading to school. I don't want the motorcycle to sit without oil over the weekend, so I will drain all its guts when I get back. (Though, it would have been nice to figure out what the problem with the starter motor is and buy replacement parts if need be so they can be shipping while I'm away).

Next things to do:

  • Drain engine oil and coolant. 
  • Remove the starter oil and check its bearings, coils, brushes, can for anything that might be preventing it to spin. 
  • Fix the problem (order any necessary components) and replace oil and coolant fluids. 
  • Tighten up loose bolts around the frame (seat arm and shifting lever). 
  • Long term: Carbon fiber fairings! :)

Mikuvan and *.mtrcl. Vehicles destined to remain gas guzzlers.

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