Starter Problem?

[FlatFenders]

I recently bought a 1957 Johnson Seahorse 35hp motor. I rebuilt the carb and can get it to run for a couple seconds by using the rope starter. This process is very tiring and I would like to be able to use the electric motor. The starter motor will spin the motor very fast with both spark plugs removed as expected but with the plugs in, can just barely turn it over even once before the motor gets hot and starts to smoke. I suspect the starter motor is bad but have no experience with what the normal operation characteristics are and hate to stick more money into this starter motor if I am unable to get the outboard to run. I find it odd that the starter motor will turn the same direction regardless of the polarity of the battery cable I jump to it. Is a good fuel mix 32:1? Is a good starting point for the low speed jet 1-1/2 turns? What should the high speed be set to for starting?

 

[JB]

Re: Starter Problem?

Howdy, FF.<br /><br />Welcome to iboats. <br /><br />Just to confirm, that should be a model RDE-19.<br /><br />First, the fuel mix. Use 24:1 for that engine.<br /><br />It is normal that a series wound DC motor turns the same direction regardless of polarity. To reverse direction you must reverse the armature/field relationship.<br /><br />Get a voltmeter and measure the voltage from the hot terminal to the case of the starter motor when it is engaged. It should exceed 9.5 volts for normal operation. <br /><br />If it does not, go to the Engines FAQs for Outboard wont start and troubleshoot the circuit. <br /><br />You may have a bad starter, but it is much more likely that you have a bad connection, a bad solenoid or a weak battery.<br /><br />Good luck, and let us know what you find.

 

[FlatFenders]

Re: Starter Problem?

I tried jumping from a known good battery, still in a car with the motor running directly to the terminals on the Johnson starter motor. In most cases, it will make almost 1 revolution, then hesitate and if I remove the jumper cable and then touch it again, it will repeat. It acts like there is too much compression for the starter to turn it over. I can start the motor with the rope but it also takes quite a bit of effort to do that. The compression release linkage seems to be working properly. I will try measuring the voltage on the starter when it is cranking but that might be hard to do since it will not continue to turn over unless I take the spark plugs out.<br /><br />Thanks for the reply, Dennis

 

[MCM]

Re: Starter Problem?

In your first post you said the motor got hot and smoked, were you refering to the sarter motor?<br /><br />that something their not supposed to do.<br /><br />If you've got an auto parts store near by, autozone, etc. you can take it in and have them run a test on it. You don't neccessarily have to buy one<br /><br />Mike

 

[Seasport]

Re: Starter Problem?

The starter motor, battery, cables & connections all need to be in good order for your starter to operate. Starter problems can be hard to diagnose. It doesn't take much to upset correct operation.<br /><br />There's a big difference in starter motor turning effort for a motor with and without spark plugs. So even a poor starting system will turn over a motor without plugs.<br /><br />I presume you have access to a voltmeter. If so, I suggest you start by measuring the voltage directly across the starter motor during cranking under load, i.e. between the starter motor +ve terminal and the case of the starter motor. If this is greater than about 9.5V suspect a starter motor problem (as JB says).<br /><br />If the voltage is less than 9.5V you are dropping volts somewhere else. Any resistance in the circuit will lead to voltage drop (and heat build up) and take power away from the starter motor. Check and clean all of the connections from the +ve battery terminal to the starter solenoid and from the solenoid to the starter motor. (As a clue, any bad connection should get warm when cranking).<br /><br />Check & clean also the -ve battery terminal & earth connections and also the earth connection from the starter motor to the engine.<br /><br />If this doesn't fix the problem, you may have a bad solenoid. If you have access to a voltage meter you can use the following tests to isolate the problem. Measuring from a good earth or preferably directly from the battery -ve terminal, work through the starting circuit and measure the voltage at each point in the circuit while cranking the motor under load: battery +, solenoid battery side, solenoid starter motor side, starter motor +ve terminal and starter motor case. The difference between these measurements will tell you where the volts are being dropped and hence where the high resistance is.<br /><br />Also make sure your battery is in good shape. The battery voltage shouldn't drop below about 10V when cranking.<br /><br />If the starter motor is turning over very slowly, the voltages will also go up and down slowly. Just take a consistent set of readings.<br /><br />Note that taking a voltage reading even if the starter motor is hardly turning will tell you how many volts are being fed to the motor. Say it's 10V at the starter motor and it's hardly turning, then you've probably got a problem with the starter motor<br /><br />Note that jumper cables can give variable results. It's easy to drop a few volts in a poor jumper cable connection.

 

[byacey]

Re: Starter Problem?

Make sure the starter bushings / bearings aren't worn. If so, the armature will be dragging on the field pole pieces and will not have a lot of torque. This is evident when you inspect the armature.