Starter Woes

[AllenGrant]

Hi<br />I have read all the threads and need some advice.<br /><br />I have a 1990 Evinrude 175 XP. It ran great (always a hard starter, but not bad) until last week. The starter seemed to have a lack of power, i.e it can barely turn the flywheel. So, I did all the troubleshooting, including a hookup to my truck battery and decided to have the starter rebuilt. New brushes, bendix assembly, etc. The starter guy says it is good to go. Same problem--seems to lack power, can't spin the flywheel much at all. I took out the plugs and it spins fine without load--blew a bunch of fuel out of the cylinders, replaced plugs, and I still have the starter bogging down on the motor. Is this a compression problem or a starter problem? How can I determine? Many thanks. I am getting frustrated!

 

[Seasport]

Re: Starter Woes

Starter problems can be hard to diagnose. It doesn't take much to upset correct operation.<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. There could still be a problem with a shorted armature winding or worn bush (although unlikely if you have had it serviced & checked out).<br /><br />If the voltage is less than 9.5V you are dropping volts somewhere else (more likely). 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 perferably 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.

 

[R.Johnson]

Re: Starter Woes

Check your battery cables at there connectors', and the ground connector at the engine. Jump the battery straight to the starter, and see what happens.

 

[AllenGrant]

Re: Starter Woes

Hi, when jumping straight to the starter from my truck battery, I have the same problem. I will rerun the volt tests in the AM. I am still thinking that this could be a compression issue. Any way of telling if the motor has too much compression, such as from fuel or water in the motor?

 

[Seasport]

Re: Starter Woes

You have to be a bit careful about jumping to conclusions when using jumper cables, as you can easily drop volts in the jumper cables & connections. It doesn't take much when you're drawing 150A plus. Better if you can substitute the truck battery for the boat battery.<br /><br />It's conceivable that you still have a starter motor problem. Can you turn the motor over by hand (without sparkplugs)?

 

[AllenGrant]

Re: Starter Woes

ok--will try. with the plugs removed, the motor starter will spin the flywheel, but bog down after two of six plugs are in place.

 

[AllenGrant]

Re: Starter Woes

Hi again<br /><br />Here is what I have. battery leads are 12.80, and 11.12 under load. when i check the load voltage on the top of the selenoid, I am at around 8.5, same 8.5 or so on the selenoid pos output to the starter. This indicates to me that my pos cable from the battery is suspect. I replaced the ground, but not the pos--so, I'll shorten up with new cables for the next test and will let all of you kind folks know what happens.<br /><br />Allen

 

[AllenGrant]

Re: Starter Woes

starting to get some spin now after replacing the positive wire! I am still going to clean up the selonid contacts, and work on getting her started agin.

 

[Seasport]

Re: Starter Woes

Sounds like you are on the right track. You shouldn't be getting anything like 2.5V drop in the +ve cable. I think you'll be away now.