Merc trim solenoid - potential hack for longer life?

Bondo

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I'm actually a mechanical engineer

Ayuh,....... That explains it,........

My 1st thought readin' yer thread was Neat trick, wish I better understood electronics,......

My 2nd thought was, But Why,..??..??

My ole tinbarge has had the same trim pump, Complete, solenoids included, for the last 20 Years,.....
ain't replaced None of it,.....
'n it's been swimmin' several times,..... :rolleyes: unlike starters, this thing is still screamin' along,....
 

achris

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May 19, 2004
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Ayuh,....... That explains it,........

My 1st thought readin' yer thread was Neat trick, wish I better understood electronics,......

My 2nd thought was, But Why,..??..??

My ole tinbarge has had the same trim pump, Complete, solenoids included, for the last 20 Years,.....
ain't replaced None of it,.....
'n it's been swimmin' several times,..... :rolleyes: unlike starters, this thing is still screamin' along,....

Yep, mine are the same. But I have a couple of customers who I know don't use the trim switch nearly as much as me, and they seem to pop those things regularly.

I'm an electronics tech, specialising in computers and underwater robots, and I do a little weldering on the side (and boat engine repairs and maintenance).... I like things like this (diode fix) that lengthen the life of a product. Really gets my goat the current 'throw it away and buy a new one' mentality! :mad:

Chris........
 

AShipShow

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Yep.. I bet the solenoids I pulled off this 96 bayliner would have functioned just fine (did when I bought it last year). The multimeter I tested them with only supplies a few volts thru the leads... not enough to break thru the carbon buildup and oxide. So I was getting kOhm ratings across the solenoid (should be only a couple ohms)

no doubt these things last, but they are being abused electrically, and for a couple dirt cheap diodes, why not potentially make them a part that you will never replace. (Maybe lol)
 

AShipShow

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Not sure if anyone cares, but just posted the video on my youtube channel of the actual test/process...

 

Mischief Managed

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Ayuh,....... That explains it,........

My 1st thought readin' yer thread was Neat trick, wish I better understood electronics,......

My 2nd thought was, But Why,..??..??

My ole tinbarge has had the same trim pump, Complete, solenoids included, for the last 20 Years,.....
ain't replaced None of it,.....
'n it's been swimmin' several times,..... :rolleyes: unlike starters, this thing is still screamin' along,....

For me, the key to this is to prevent inopportune failure. The last time one failed on my boat, I was in a busy area where wakes are massive. Having the inability to trim down to get on plane after slowing for big wakes really sucked. I ended up laying on top my hot engine while bobbing around like crazy and shorting the terminals on the down solenoid to get the drive down.
 

AShipShow

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Nothing on boats fails at a convenient time lol...

Last time I was out boating, a guy was loading at the ramp, and couldn't get his drive to go up (believe it was a volvo). The way his boat was layed out, there wasn't any access to the trim pump without disassembling his interior... He didn't have a choice but to drag out and grind the skeg to a nub...

By the time I got there was too late to tell him to remove the rams, but anyways... just tryin to prevent myself from that situation.
 

achris

More fish than mountain goat
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May 19, 2004
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Added my 'solenoid savers' today... :D

Thanks Mad Props

Chris...........


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Easy to make. Any electronics shop will sell 1N5404 (400v, 3A) for pennies. A couple of 1/4" (6mm) ring connectors, a 'joiner' and a short length of wire..



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.Assemble it all and crimp the connectors.... (managed to push the diode all the way into the crimps. Adds mechanical strength and also help stop moisture getting in ;))



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Installed on the starter slave solenoid...



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And the trim pump. (I have my 'solenoid bypass switch' added, and just hooked them to the switch terminals)..
 
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AShipShow

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Nice! looks nice and clean! Hopefully those are the last solenoids your boat ever needs :D
 
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