84 mercury 115 6 cyl temp gauge

[davidstill1]

recently purchased a 15 foot tidecraft with an 84 mercury 115 6 cyl. two stroke the only gage installed is a speedometer.
I would like to add a tach and a temp gauge.I downloaded a manual for the motor and figured out the tach.I need to find out if i can connect a temp gauge to this motor.I do not see any sending unit and i have not found the wires that would connect to sending unit.if i cant add a temp gage then what should i use to make sure the motor is running at the right temperature.Any help will would be appreciated thnx

 

[frankenmerc]

Re: 84 mercury 115 6 cyl temp gauge

I find the best way keep it running cool is to change the water pump at least once a year at minimum,but if you want to run a guage there should be a brass plug on the front cover you would have to remove the plug and install a sending unit there then run your wires and guage.
Good luck

 

[Texasmark]

Re: 84 mercury 115 6 cyl temp gauge

if you want to run a guage there should be a brass plug on the front cover

What front cover, where? I have installed them in the water jacket cover that the plugs stick through. If you don't have a tapped, plugged hole made for it, make your own. Drill and tap a hole to suit the sending unit. As I recall, there were no plugs years ago before the newly designed "lost foam" castings associated with the cylinder count reduction which has one. I have had/have both engine models.

Mark

 

[frankenmerc]

Re: 84 mercury 115 6 cyl temp gauge

What front cover, where? I have installed them in the water jacket cover that the plugs stick through. If you don't have a tapped, plugged hole made for it, make your own. Drill and tap a hole to suit the sending unit. As I recall, there were no plugs years ago before the newly designed "lost foam" castings associated with the cylinder count reduction which has one. I have had/have both engine models.

Mark

Cylinder Block Cover! where your spark plug holes are, if your model has the tapped hole with the plug in it it will accept Mercury Quick Silver Part #12415 sender this is what i have done on mine and had to run a wire from the sender to the guage worked for me.
I have 6 / I L -6 engines from 1974-86 and most if not all have the tapped hole on the cylinder block cover.
hope this helps

 

[Chris1956]

Re: 84 mercury 115 6 cyl temp gauge

Most inline 6 motors do not have a thermostat. You will therefore get wildly divergent temps. I would recommend a water pressure gauge instead. Install the brass pressure nipple in the same spot recommended for the temp sender.

 

[davidstill1]

Re: 84 mercury 115 6 cyl temp gauge

Thanx everyone for helping another newbie.I found the plug in question.Since the motor is New to me I went ahead and ordered a new water pump just to be safe. I am gna go with the pressure gauge instead of temp . Does anyone know what sending unit or kit I should get.

 

[oldman570]

Re: 84 mercury 115 6 cyl temp gauge

Fiara makes a pressure gauge and a installation kit that will fit most all motors. A gauge that reads from 0 to 30 PSI is the best as a water pump will only push about 4 or 5 pounds at idle with a new impeller and around 15 to 18 when at WOT. A temp gauge can also be instaled by using a 1/8" pipe nipple and T and placing both the pressure and temp sender in the T. That way you can have both gauges. There are several places to buy the gauges on the net as well as here on Iboats. You should be able to wire a hi temp warning light to the sender on a exesting sender also. Check the Faira website for more info. JMO
Oldman570