Burning up starter solenoids...why?

CaneCutter79

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I'm on my 3rd starter solenoid right now within the last 2-3 months. I have a '79 Evinrude V4 85hp outboard. My starter is good, the battery should be fine, so why am I having to replace the starter solenoid again for the third time?

I have used a volt meter on each solenoid lead while someone would assist and turn the key (starting the motor) to check voltage readings. I get full voltage to the top of the solenoid for the battery lead (obviously) and full voltage to the bottom where for the lead goes to the starter. (12-13 Volts depending on battery charge)

Here is an assembly picture of the solenoid:
http://www.boats.net/_search/images/parts_brp/41494306.png

There is a ground on the bottom-middle of the solenoid and another lead on the top-middle goes somewhere back to the switch for engaging the solenoid at the key switch. There is also an additional lead on the top "direct to battery" lead that goes back to a rectifier on the opposite side of the motor and the rectifier connects to a terminal lead that goes to the power pack, etc. That's the lead that is back-feeding current up to and over 24v at times. When someone turns the key, everything is fine until they stop turning the key and a backfeed voltage sometimes appears for a split second. Could the rectifier go bad and cause the backfeed?

My battery is an Everstart Max with over 700CCA. I'm not crazy about the battery but it came with the boat. If it works, I'll just continue to use it for a while until I can get a better one. I just want to resolve the issue of the solenoids burning out or whatever is happening to them.

Any help is very much appreciated.
 

tashasdaddy

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Re: Burning up starter solenoids...why?

what do you battery cables look like, they can read 13 volts, and only deliver 2 or 3 amps. thus burning up the solenoid. corrosion on connections and cables get nicked and corrode, reduces the power to the solenoid and starter, creat heat. nicked cables corrode from the inside out, i have found cables with only 3 or 4 strands still good.
 

F_R

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Re: Burning up starter solenoids...why?

Trying real hard to follow your description, it sounds like you are measuring a voltage surge at one of the yellow rectifier leads? Am I right? Telling us the wire colors might help to follow you.

Well, I can't explain what you are seeing or know why you are even looking there. The yellow leads to to the alternator and have nothing to do with the starter solenoid except both are connected to the battery. If I read you right, you aren't seeing voltage spikes at the battery (top post on the solenoid).

Exactly what is happening to your solenoids? Is the primary coil going bad or are the relay contacts going bad?
 

James R

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Re: Burning up starter solenoids...why?

How many batteries do you have connected on the boat? If you have more than one you could be getting 24Volts through a wiring error.
Disconnect the positive switching wire from the solenoid and test for voltage with the the starter key turned. You should have only 12Volts.
 

CaneCutter79

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Re: Burning up starter solenoids...why?

I'll get some pictures that of the actual motor and post them. that will help answer some of the questions to my questions. :D

I'll also look at the cables and connections. Yes, I'm getting over 13volts but I'll check the amp load.
 

Vic.S

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Re: Burning up starter solenoids...why?

There is a ground on the bottom-middle of the solenoid and another lead on the top-middle goes somewhere back to the switch for engaging the solenoid at the key switch
I would not be surprised to see a brief high voltage on this lead when the key switch is released, but it would be of no consequence.

My thoughts at the moment are that you have a very large, in terms of CCA, battery. It may be maintaining a much higher voltage than one with a lower CCA would while the motor is being cranked. This would mean a higher current would be flowing through the solenoid coil. You say 12-13 volts measured at the connection to the starter motor thats significantly higher than I'd expect!

Possible that would be causing the solenoid coils (if it is the coils, but you have not confirmed that) to burn out.

Just a theory but clutching at straws rather.

Fitting good quality replacement solenoids or buying cheapies? Or having to crank for long periods to start?
 

14ftgrumman

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Re: Burning up starter solenoids...why?

Silly question, but are you getting solenoids from a marine dealer that are OMC/BRP or comparable?(Sierra or Mallory) Or are you geting solenoids from the auto parts store and the counter person is giving you starter solenoids made for Fords?
There is a huge difference between automotive and marine everything.
 

McGR

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Re: Burning up starter solenoids...why?

What is the failure mode of the solenoids?

Are the coils going open?

Are the coils shorting?

Are the solenoids actuating (clicking) but not providing a high current path?

Are they mechanically binding?

The is really only three things that determine if a solenoid is working properly - the coil circuit, the high current circuit and the mechanical mechanisms. If you can narrow down the manner in which the solenoids are failing, it will be easier to figure out what is going wrong.
 

Daviet

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Re: Burning up starter solenoids...why?

Just thinking, have you checked your starter draw? High starter draw and cheap solenoid will cause problems.
 

CaneCutter79

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Re: Burning up starter solenoids...why?

What is the failure mode of the solenoids?

Are the coils going open?

Are the coils shorting?

Are the solenoids actuating (clicking) but not providing a high current path?

Are they mechanically binding?

The is really only three things that determine if a solenoid is working properly - the coil circuit, the high current circuit and the mechanical mechanisms. If you can narrow down the manner in which the solenoids are failing, it will be easier to figure out what is going wrong.

WOW! Tons of questions and good information here. I know practically nothing on most all questions!:D

I do not know what coils are in the solenoid. I can't take it apart to see what's failing. All I know is, the choke will click if you push in on the key and I believe you can hear a faint click without the choke. I'd have to check it again to see but it's pretty quiet and doesn't make much noise unless you push the key in to choke the carb. THen you can hear the choke engage.

I am buying OMC parts from a marine dealer, no automotive parts. The last two solenoids I bought have been Sierra 18-5808 which replaces OMC 3954519, 58708 and Mercury 47886.

Sorry if I cannot help give you better info on how I know they are failing. I just know the current path is not getting to the starter post on the bottom.

If I recall, I can get 12.74 volts on the bottom pole to the starter when the key is turned over.


The battery has 700cca and no, I am only using a single battery. My boat mechanic told me the battery was too small but would work. It's not a deep cycle battery and no, there are not long periods of cranking. The motor usually fires up pretty quick even when cold.

I have not checked the pull on the starter because I do not know how. I would be glad to do so if someone can explain how....


Here are some pictures that show the motor.

Solenoid1.jpg


Solenoid2.jpg
 

tashasdaddy

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Re: Burning up starter solenoids...why?

i don't see anything wrong. sorry.
 

James R

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Re: Burning up starter solenoids...why?

Check the integrity of the rubber insulator under the clamp. Had a solenoid problem when the insulator was not fitted correctly. I still don't understand why but when the insulator and clamp were correctly fitted it worked fine. I suspect clamping incorrectly caused distortion of the case.
 

F_R

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Re: Burning up starter solenoids...why?

Let's not get confused by the choke, althugh that is an indication that you at least have power to the key switch.

OK, from what I've been able to gather from your testimony, your starter solenoid is clicking. That means the primary coil in the solenoid is good and all the other wiring up to that point is also good.

If the solenoid clicks and the starter doesn't run, there are only a few possibilities:

1. The relay contacts within the solenoid are bad. That is what you seem to be suspecting. However, that truly is a rare thing to happen, and nothing outside causes it. Well, I suppose a shorted starter could but it wouldn't work after you replaced the solenoid either. Which brings up another possibility:

2. Are you 100% sure the problem isn't the starter and not the solenoid? Have you checked the voltage at the bottom post and/or the starter terminal when it ISN'T WORKING? Checking it when it works doesn't tell us much. If you have somewhere around 12 volts at the starter AND it dosn't crank, the starter is at fault.----OR it isn't grounded. Which brings up another possibility:

3. Grounds. Are you 100% sure you don't have a grounding problem? That is responsible for an awful lot of starting problems and the solenoid mfrs are getting rich replacing perfectly good solenoids.

4. 12.7 volts at the bottom terminal doesn't sound right. Is the starter running when you are seeing that voltage? It certainly should be. If it isn't, see #2 and 3. Something less than 12 volts is the norm with the starter cranking. You have to catch it when it is dead and do your measurements then.

If you can answer these specific questions, I think we can get to the bottom of this.

BTW, intermittant starter problems are common. By that I mean dead today and OK tomorrow. That goes along with high voltage at the terminal when it is supposed to be cranking, but is dead.
 

CaneCutter79

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Re: Burning up starter solenoids...why?

See bold red text below for answers

Let's not get confused by the choke, althugh that is an indication that you at least have power to the key switch.

OK, from what I've been able to gather from your testimony, your starter solenoid is clicking. That means the primary coil in the solenoid is good and all the other wiring up to that point is also good.

If the solenoid clicks and the starter doesn't run, there are only a few possibilities:

1. The relay contacts within the solenoid are bad. That is what you seem to be suspecting. However, that truly is a rare thing to happen, and nothing outside causes it. Well, I suppose a shorted starter could but it wouldn't work after you replaced the solenoid either. Which brings up another possibility:

2. Are you 100% sure the problem isn't the starter and not the solenoid? Yes, the starter appears to be working correclty. When I replace the solenoid, everything works fine. Have you checked the voltage at the bottom post and/or the starter terminal when it ISN'T WORKING? Yes, the bottom terminal did not have any voltage at all when the key was turned over. All other terminals had the correct voltages and grounded. Checking it when it works doesn't tell us much. If you have somewhere around 12 volts at the starter AND it dosn't crank, the starter is at fault.----OR it isn't grounded. Which brings up another possibility:

3. Grounds. Are you 100% sure you don't have a grounding problem? That is responsible for an awful lot of starting problems and the solenoid mfrs are getting rich replacing perfectly good solenoids. I have just cleaned the battery posts, wire connections at the battery, and I have cleanded the wing-nuts that clamp the cables to the battery. I was getting the wing-nuts hand-tight and not super tight with a wrench. I have heard that makes a grounding problem.
4. 12.7 volts at the bottom terminal doesn't sound right. Is the starter running when you are seeing that voltage? Yes It certainly should be. If it isn't, see #2 and 3. Something less than 12 volts is the norm with the starter cranking. You have to catch it when it is dead and do your measurements then.

If you can answer these specific questions, I think we can get to the bottom of this.

BTW, intermittant starter problems are common. By that I mean dead today and OK tomorrow. That goes along with high voltage at the terminal when it is supposed to be cranking, but is dead.
 

CaneCutter79

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Re: Burning up starter solenoids...why?

Check the integrity of the rubber insulator under the clamp. Had a solenoid problem when the insulator was not fitted correctly. I still don't understand why but when the insulator and clamp were correctly fitted it worked fine. I suspect clamping incorrectly caused distortion of the case.

Good idea. The rubber insultator is thin and dry. Not in the best shape. I have used a rubber shim to help secure the solenoid.

I assume I need to replace the rubber insulator correct?
 

tashasdaddy

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Re: Burning up starter solenoids...why?

piece of bicycle inner tube works well. best to get rid of the wing nuts, and use regular hex nuts.
 

F_R

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Re: Burning up starter solenoids...why?

OK canecutter, in light of your red-lettered answers I have to conclude you are indeed going through an unreasonable bunch of solenoids. I have no explanation as to why. But your details show that it is the relay contacts that are burning and there is no logical outside reason for that. Are you just an unlucky guy? Hey, just kidding.

I still say that 12.7 volts at the starter while cranking is remarkable. Dang good battery and starter and super-low voltage drop!!!! That's good.
 

johnny 30

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Aug 14, 2009
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Re: Burning up starter solenoids...why?

hello canecutter:At this point I would remove starter and check brushes, not a big job.If motor at any time was hard to start or bendix gear was sticking in the up poisition while cranking motor,the resistance would go up on the brush wires and burn them up.If brushes need to be replaced,use a putty knive with notch cut out of it to hold brushes in place while reassembling so armatue can seat against brushes.Your motor is 30 years old it's time for new ones
 
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