SMX Exhaust Heat Alarm Install

[Patrick Mangum]

In the process of installing the SMX exhaust heat sensing switches on my exhaust elbows.  I had intended to place the switches further up on the elbow but I was having trouble getting the sensors to sit flush on the elbow surface.  Currently have them at the bottom of the elbow with the hose clamps on the edge of the exhaust hose.   Are they ok where I currently have them placed? 

For the wiring, does it matter which tab is connected to ground and which goes to the alarm panel?

Topic

[Clark Leighs]

Yes, the snap switch must be mounted metal to metal.    The hose will be an insulator and will delay any reaction of the switch to mounting heat.  Maybe long enough to negate its effectiveness.

[Tom Jerome]

Moved

I posted the photo of the engine and moved it up to the exhaust elbow. Thermal conductivity of the metal elbow would be better imho. And a early warning. If im wrong let me know, thanks

[Tom Jerome]

I have it connected on the rubber part between elbow and muffler now which i assume it needs to be moved up to the exhaust elbow on the metal.

[Rob Schepis]

Post some pics of your setup.

[Tom Jerome]

i guess you would also call it the muffler, the fiberglass exhaust. On my setup there is a rubber hose between the exhaust elbow and the fiberglass muffler. My current setup has it on that hose and these were installed when I purchased the boat. They are not SMZ brand and their setpoint is 200 deg F. I guess I should move it up to the exhaust elbow?

[Rob Schepis]

Rubber hose at exhaust manifold?  Did you mean muffler?  No, the temp sensors designed for the wet exhaust hose are at a lower set point temp. 

[Tom Jerome]

thanks for photo

so the sensor must go on the exhaust elbow metal part? Can it go on the rubber hose part between the elbow and the exhaust manifold?

[Patrick Mangum]

Understood.  Thanks guys 

[Rob Schepis]

Wiring orientation does not matter, it’s just an open switch that shorts to ground at preset temp.

[Tony Athens]

As long as it the sensor  bottom  and elbow surfaces touch each other, it looks good to me…

[Author]

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