I would like an over-temp alarm. What is it going to take?

series60

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Title pretty sums it up. I would like an over-temp alarm. What is it going to take? I'm running a high mileage, saltwater 305 and would like to install an over-temp alarm. Have no idea what to look for. Boat in question in sig file.
 

tpenfield

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Re: I would like an over-temp alarm. What is it going to take?

The mercruisers have them . . . but perhaps your engine is before they were standard equipment.

It will take the sender switch and a buzzer at the helm. The sender switch goes into the thermostat housing opposite the temp gauge sender.
 

series60

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Re: I would like an over-temp alarm. What is it going to take?

Thanks for the quick come back. This ole' 305 has the temp sender in the manifold. The are two brass plugs in the thermostat housing which might accept a sender switch. I'll do some research.
 

Don S

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Re: I would like an over-temp alarm. What is it going to take?

Radio shack 12V buzzer and a Normally open temperature switch that closes at 200? to 210? and some wire.
Which thermostat housing do you have. A picture would help.
 

series60

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Re: I would like an over-temp alarm. What is it going to take?

Thanks Don, on my way to RS.
 

Failproof

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Re: I would like an over-temp alarm. What is it going to take?

Go to a napa or such. Look for a sender from something like a 60's or 70'st car that had idiot lights - the sender grounded out, the light came on. In your case, the buzzer comes on. Have them look up the specs on it, it will say what it is. Normally open, normally closed, what trigger temp etc.
 

Failproof

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Re: I would like an over-temp alarm. What is it going to take?

And if you already have a low oil alarm that is negative controlled, then you need not the piezo buzzer. Tie into it, it will sound with overheat or low pressure. Heck if you dont have oil alarm, now would be time to add it. Make sure your getting normally open senders, and check the trip points are what you want.
 

scarpint

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Re: I would like an over-temp alarm. What is it going to take?

Not to high-jack the thread, but I have this alarm on my boat and I cannot find the sender unit in any of the documentation. I need to replace mine, and perhaps the temp gauge sender unit as well. I can see both on the thermostat housing, and can find the gauge sender in the microfiche but not the hi-temp sender.

Any ideas?

Thanks!
 

Don S

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Re: I would like an over-temp alarm. What is it going to take?

Not to high-jack the thread, but ..............Any ideas?

Then start a new thread and ask your question, seems to be just as easy as hijacking someone elses thread.
 

scarpint

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Re: I would like an over-temp alarm. What is it going to take?

You'll forgive me if they seemed just mildly related.

Sheesh.
 

Silvertip

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Re: I would like an over-temp alarm. What is it going to take?

Mildly related is not the point. This is not a "mildly related thread". Every thread on this and the other iBoats forums are intended to be specific to the problem stated in the original post. By jumping in with unrelated questions makes staying on track with the original problem very difficult. Imagine what it would be if there were five or six "mildly related" comments thrown in. Put yourself in a mechanics shoes. You are talking to a customer about HIS problem and another person ambles up and begins bending your ear about his problem while a third person also does the same thing. Tough to stay focused on the original issue.
 

thumpar

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Re: I would like an over-temp alarm. What is it going to take?

Title pretty sums it up. I would like an over-temp alarm. What is it going to take? I'm running a high mileage, saltwater 305 and would like to install an over-temp alarm. Have no idea what to look for. Boat in question in sig file.
Neat idea. Let us know how it turns out and how much trouble it is. I might have to dig in to this also.
 

wellcraft-classic210

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Sep 22, 2010
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Re: I would like an over-temp alarm. What is it going to take?

You may want to look into this --- Sierra MP41400 Audible Engine High Temperature and/or Low Oil Pressure Warning Kit

Its availalbe for less than $40.00.

I added this to my boat and have been happy with it.
 

rock doc

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May 29, 2011
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Re: I would like an over-temp alarm. What is it going to take?

You may want to look into this --- Sierra MP41400 Audible Engine High Temperature and/or Low Oil Pressure Warning Kit

Its availalbe for less than $40.00.

I added this to my boat and have been happy with it.

Perfect...I'll be needing on of these. Had a very close call last weekend. I'll have a closer look this weekend and see if it is compatible with my 1990 merc 4.3l.
 

artificialreef

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Feb 21, 2009
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Re: I would like an over-temp alarm. What is it going to take?

Or on this site for 28.44$ And you will be supporting this great resource and keeping it on line.
 
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