Wiring a Johnson temp guage.

[nutgunaspu]

Hi Guys, I'm after a bit of help. Finally got around to wiring up the instruments that came with the '92 140hp Johhno I bought on Ebay. The OMC temperature guage has 3 connections. +, - and a tan wire to the temperature sender on the motor. Question is ....where do I connect the tan wire. I've followed the wires from the two tempersture senders on the block and they dissapear into the CDI unit. I'm not too keen to go connecting to any of the terminals on the CDI because I know how easy it is to stuff them up.
Any ideas???
Thanks
Nutgunaspu

[BM]

The senders in your heads are actually temperature switches. These ground out if the engine overheats and short out the ignition system to prevent engine failure.

Usually to install a temp guage you need an adapter kit which has a metal bracket that is held in place by one of the waterjacket bolts and the temperature sender screws into it.

Cheers

[FNQCairns]

That wire and sender looking part is actualy a thermistor, that is triggered only at over heat.

You need another part, the sender that suits the guage, it will fit into an entirely different part of the head which may be plugged atm but will screw out and the sender screw in it's place. look for the plug.

cheers fnq

[nutgunaspu]

Thanks guys. The gauge was installed on this motor in its previous boat, so I should be able to just reconnect the wire to the motor once I find where. I have also fitted an aftermarket high temperature warning alarm, the sensor for it just goes under one of the head bolts. It works well, actually giving a digital readout of the motor temperature. Handy for knowing at what revs your engine is running its hottest.
Heres the link
http://cgi.ebay.com.au/MARINE-ENGINE-TEMPERATURE-GAUGE-SENSOR-ALARM_W0QQitemZ130228065356QQihZ003QQcategoryZ2645 1QQssPageNameZWDVWQQrdZ1QQcmdZViewItem