Engine Alarms

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Private Nemo

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Hi ,

I have twin 1985 260 Mercruisers. I would like to install some alarms. Such as overheat , stalling etc. How do I do that and where do I get them ?

thanks

Drew
 
Don S

Don S

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Re: Engine Alarms

I just did a post on that exact subject with low oil pressure and overheat, look here http://forums.iboats.com/non-repair...hooking-up-oil-p-water-temp-alarm-589724.html
Low oil pressure alarm will come on if the engine dies and the oil pressure drops with the key still on. Then a quick look at the tach to confirm.

You can get the alarm buzzer at radio shack, the switches you can get from your local auto parts store, or even here at iboats.

Here are the oil and temp switches from here at iboats.

http://www.iboats.com/SWITCH-OIL-PR...5507952--session_id.475239986--view_id.926958 1/2 npt

http://www.iboats.com/SWITCH-TEMP-2...5507952--session_id.475239986--view_id.926935 with 3/8"npt (wrong in the discription, there are no 1/8NPT temp switches.
 
Bondo

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Re: Engine Alarms

Private Nemo said:
Hi ,

I have twin 1985 260 Mercruisers. I would like to install some alarms. Such as overheat , stalling etc. How do I do that and where do I get them ?

thanks

Drew
Click to expand...

Ayuh,.... Overheat, low oil pressure, 'n bilge water levels are pretty easy, just follow don's link...

As far as Stallin',.... Can't you already tell the motor Quit,..??
 
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Don S

Don S

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Re: Engine Alarms

Bond-o said:
Ayuh,.... Overheat, low oil pressure, 'n bilge water levels are pretty easy,
Click to expand...

Just a note on that. DO NOT hook up a bilge alarm on the engine circuit, or the alarm will not work when the key is off.

Plus, it needs to be a different sound so you know if you have engine problems or water in the bilge without having to go look.
 
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Private Nemo

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Re: Engine Alarms

So I have to put seperate switches in the motors from the ones already there?. I cannot tap off the wires that come from them behind the dash ???
 
Bondo

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Re: Engine Alarms

Private Nemo said:
So I have to put seperate switches in the motors from the ones already there?. I cannot tap off the wires that come from them behind the dash ???
Click to expand...

Nope,.. The gauges use Senders, 'n alarms use a Switch...

Senders are varying resistance, 'n Switches just go to ground...
 
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Private Nemo

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Re: Engine Alarms

Thanks for all the replys. They are what I needed. Just one more thing. How do I install an alarm for a stalling motor.?

thanks Drew
 
tazrig

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Re: Engine Alarms

Nemo, when your engine stalls your oil pressure will immediately drop to zero and set off the oil pressure alarm buzzer so you already have one built in once you instal the oil alarm buzzer. Also when you turn your key to the on position and while your are starting the motor and for a second or two after it starts (until the oil pressure builds up) the oil alarm will sound.
 
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Private Nemo

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Re: Engine Alarms

Hi, Now that the weather has finally broke a little , time to get to work.. So I starting to put this alarm , but do not know where to put the oil sender.

Any suggestions are appreciated.

Drew
 
Don S

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Re: Engine Alarms

2 ways to do it, best way is to remove the plug just above the block oil filter boss. Depending on your switch, you may need a reducer to extend the hole out to where the switch can be installed without hitting the block.
Another option, is to tee into the gauge sender fitting back by the distributor. Use steel not brass for the tee and do not use teflon tape, simple gasket sealer works best and still gives you a good ground.
 
Bondo

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Re: Engine Alarms

Private Nemo said:
Hi, Now that the weather has finally broke a little , time to get to work.. So I starting to put this alarm , but do not know where to put the oil sender.

Any suggestions are appreciated.

Drew
Click to expand...

Ayuh,.... There should be a plugged oil port at the base of the distributor, 'n another down low portside aft on the block, by the oil filter housin',...
Or you can tee off the oil pressure gauge sender...

'n yer installin' Switches for an alarm, not Senders, which are for gauges...;)
 
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Private Nemo

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Re: Engine Alarms

Ok , switches. i will check for those spots. I was trying to find a spot for the water Switch , but the only one I see is for the sender unit for the gauge. Is there another spot like where the sender is

thanks

Drew
 
Don S

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Re: Engine Alarms

Should be a pipe plug on the opposite side of the intake from the gauge sender.
 
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Private Nemo

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Re: Engine Alarms

OK, I have climb all over these engines , I do not see any place to put these switches. I looked all around the dist and oil filter. Granted its pretty tight in the bilge. I am open to any suggestions on how to install theses switches . I was really looking forward to having theses alarms.

thanks

Drew
 
achris

achris

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Re: Engine Alarms

Don S said:
...Another option, is to tee into the gauge sender fitting back by the distributor. Use steel not brass for the tee and do not use teflon tape, simple gasket sealer works best and still gives you a good ground.
Click to expand...

Only it's not by the distributor, it's above the oil filter...
 
Don S

Don S

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Re: Engine Alarms

I know Merc put them both down low, but Volvo used them up by the distributor (easier to get to and dryer), and why I mentioned that location. So, am I still allowed to say it?
 
Bondo

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Re: Engine Alarms

achris said:
Only it's not by the distributor, it's above the oil filter...
Click to expand...

Ayuh,.... There Is in fact a pressurized oil port, with a plug in it, at the base of the distributor,...

even if Merc uses the port by the oil filter...
 
Bondo

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Re: Engine Alarms

Private Nemo said:
OK, I have climb all over these engines , I do not see any place to put these switches. I looked all around the dist and oil filter. Granted its pretty tight in the bilge. I am open to any suggestions on how to install theses switches . I was really looking forward to having theses alarms.

thanks

Drew
Click to expand...

Well,... We've told ya where to Look,...

Short of flyin' over, 'n puttin' a finger on 'em, ya gotta Look closer...

Btw,... For the water temp switch, there should be a port opposite the temp sender, Or, in the water runner in the intake manifold, just ahead of the carb...
 
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