81 pmc ford 351 inboard temp sensor

[boaterjoejoe]

Hello, I have been working on restoring an 81 mastercraft with a pmc ford 351 cooled with lake water.

This weekend I had it out on the lake for the first time.

I need help trouble shooting the Gauges. I checked and they have voltage and good fuses, but I dont know where they connect on the engine side.


Where are the sensors / connections located for the temperature gauge?

Where does the tachometer wire connect to the engine?

Where does the voltage - amp gauge wire attach?

Any help would be great!!!

 

[iqxoqlms]

Re: 81 pmc ford 351 inboard temp sensor

I am almost done with a resto on a 1984 Ski Supreme - same power.

There should be a blue wire that connects to the top of the water temp sensor which is in the intake manifold right behind the thermostat housing.

There should be a gray wire that connects to the tachometer and the negative side of the coil.

I believe the Amperage gauge pulls out of the electrical system...don't believe there is a dedicated wire running to the alternator to run that gauge.

Hope this helps!

Mark

 

[boaterjoejoe]

Re: 81 pmc ford 351 inboard temp sensor

I am almost done with a resto on a 1984 Ski Supreme - same power.

There should be a blue wire that connects to the top of the water temp sensor which is in the intake manifold right behind the thermostat housing.

Hope this helps!

Mark

It surely does help, but, Im learning as I go here so, what does the thermostat housing look like? and where is it located?

 

[haulnazz15]

Re: 81 pmc ford 351 inboard temp sensor

Thermostat housing is right in front of the distributor cap (slightly to the left of it actually.

 

[iqxoqlms]

Re: 81 pmc ford 351 inboard temp sensor

Here is a picture of my engine. The thermostat housing is the deal below the arrow into which the hoses are connected. Immediately behind the thermostat housing is the temp sending unit. It cant be seen in this picture but it is under the spark plug wires.

 

[boaterjoejoe]

Re: 81 pmc ford 351 inboard temp sensor

Thanks for the great Pics!

What is the normal operating temp of a 1980 351 ford pmc?

My gauge is reading warm, but it was reading 100 when the engine is cold 60 degrees from sitting over night. so I am unsure.

I couldnt find the actual temp sensor around here so I put in a different one with a reducer fitting. would that make a difference?

I just put in a new water pump, and the exit side of the pump seemed cool so it should be working. I double checked and it is installe the correct direction, LH engine, drain screw facing in.

Ideas?

 

[iqxoqlms]

Re: 81 pmc ford 351 inboard temp sensor

I have a 160 stat in my motor and it runs 160 to 180 on the gauge.

I don't think using a reduced fitting would cause an erroneous temp reading.