Engine alarm sounds when both engines are running

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Louky
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Engine alarm sounds when both engines are running

Post by Louky »

Yesterday I started both engines, flipped the engine alarm switch and it went off. I looked at the tach's and both were running. Does anyone know what I should check first?

Thanks for any help.
Louky
1987, 32' Marinette Fisherman
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Roger2
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Re: Engine alarm sounds when both engines are running

Post by Roger2 »

My first step would be to get a mechanical oil pressure gauge & make sure you have oil pressure on both.

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tundrarules
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Re: Engine alarm sounds when both engines are running

Post by tundrarules »

Look at both oil press sending units for corrosion. Take one wire off at a time to see which swith is bad. Hopefully u don't have a grounded wire..I don't think so since your oil press guage is working. Let us know what u find.
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Fastjeff
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Re: Engine alarm sounds when both engines are running

Post by Fastjeff »

You need to remove ALL of the alarm connections (Oil pressure and temp switches) on both motors. Then, with both running, put them back on one at a time until the alarm goers off.

Pain in the tush, but that's the best way.

Jeff

PS: All 6 of my temp switches use automotive style quick disconnects to make this task easier. I also separated the two motors alarm system so I can run either one alone (without the low oil pressure alarm on the other setting the alarm off). This required two simple relays and a bit of wiring. If anyone is interested, I can post photos and the schematic.
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Louky
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Re: Engine alarm sounds when both engines are running

Post by Louky »

A friend who seems to know engines helped me troubleshoot it. He disconnected the engine contacts, checked some fuses and grounds. At this point he thinks it's the alarm itself going bad. I've ordered a new one which will be in soon. I'll post the results.

Thanks so much for the replies. Very helpful.

Louky
1987, 32' Marinette Fisherman
Col. Angus
Louisville, KY
Twin Chysler 360's
Louky
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Re: Engine alarm sounds when both engines are running

Post by Louky »

Jeff, separating the alarm systems sounds like a good idea and would be great info to have on the forum. Please post the how to if it's not to much trouble.
Thanks!
Louky
1987, 32' Marinette Fisherman
Col. Angus
Louisville, KY
Twin Chysler 360's
Fastjeff
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Re: Engine alarm sounds when both engines are running

Post by Fastjeff »

No problem. I use a couple of simple relays I go on eBay (about ten bucks).

Here's the wiring diagram.

Jeff
Attachments
Alarm Relay Schematic.JPG
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Louky
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Re: Engine alarm sounds when both engines are running

Post by Louky »

Thanks Fastjeff for posting the diagram. That looks like a good project for the future.

As it turns out, it wasn't the alarm itself. After installing a new one the problem was still there. I disconnected all the leads as suggested and found that it was the alarm sender on the port engine. Super easy to replace and it now works as it should.

Problem solved. Sorry it took so long to get back to this post.

Thanks all
Louky
1987, 32' Marinette Fisherman
Col. Angus
Louisville, KY
Twin Chysler 360's
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