Is my start motor dead?

[river_bouy]

Hi Guys,
I have a 1984 Suzuki DT50 which although an old engine has always run pretty good. However, I went out today and had two major dramas.

First, I had very little power at full RPM which I believe was caused by only one cylinder firing. When I took the engine cover off, only one spark plug was warm the other was cold. Was able to drive around but only at a very slow speed. Is there a way to check the trigger voltage traveling down the wire the spark plug?

Secondly, my starter motor began not turning. I hooked a voltmeter up to the battery and it read a full 12.76 volts. I then connected it to the starter relay, and when I turned the key I can hear it click and the voltmeter reads 12.7 volts. I then hooked the voltmeter up to the + and - terminals on the start motor itself. When I turned the key the reading jumped up to 5volts. However, motor does not turn over. So I think current is getting to the starter motor right but it doesn't seem to turn. Is there a way to test/confirm this before buying an expensive new starter motor?

Thanks in advance guys.

 

[JB]

Re: Is my start motor dead?

Very likely a poor connection in the high current circuit to the starter, rb.

Go to the Engine FAQs forum and check out the troubleshooting of starter circuits in "Outboard won't start".

Let us know what you find, and good luck.

 

[river_bouy]

Re: Is my start motor dead?

Thanks JB.

Hoping it is just a connection, not a dead starter motor. I will investigate and post back what I find.

 

[cousinabe]

Re: Is my start motor dead?

remember, it's amps, not volts that matter when there's a load on the battery.
Make sure your battery amperage is still good. Autozone or any other part store can load test your battery.
A poor connection would do the same thing.

 

[river_bouy]

Re: Is my start motor dead?

Can i test the start motor by jump starting it?

I was thinking of disconnecting the current battery, and then getting auto jumper leads and attach to a known good battery, the attach cables to + and - points on the starter motor.

Would this work?

 

[river_bouy]

Re: Is my start motor dead?

Okay,
To rule out bad wiring, i bought new battery cables and connected the black - straight from the battery to the ground on the start motor (after cleaning up the connection).

Then when I connected the red + directly to the terminal on the starter, it would spark but the starter motor would not budge.

I also recharged the battery and tried with a second battery.

So, I figure replacing the starter is the only option left?

THanks

 

[JB]

Re: Is my start motor dead?

Do the steps in the article, rb.

 

[Les MacDougall]

Re: Is my start motor dead?

Only 5 volts on your Battery?

Bad Battery,

Les