Perkins 4.108 Formosa 41 Oil Sender Unit

[Alan B]

Hi All,
I have just finished rebuilding the Perkins 4.108 engine on a 41 foot 1973 Formosa boat and have a question about the oil sender unit before I start the engine for the first time.
My boat has an oil pressure gauge in the dash which I have wired to the oil presuure sender unit just besides the starter motor. It's about 2 inches in diameter.
In front of that going towards the oil filter there is another sender unit about 1 inch in diamater which I'm not sure what it is. I'm assuming it's a sender unit for an oil lamp. There is no provision in the dash for an oil lamp though.
I traced one of the wires and it just stops in the loom unconnected.
Does anyone know if it is for an oil light.
If it is then I'll just buy a dashboard lamp and wire it up.
Did these boats have an oil lamp and an oil gauge?
Any help is appreciated.


Regards
Alan

[Hampus]

We have pretty much the same boat and the same engine. Ours isn't wired either. There are cables for it but no light and no alarm. I'll connect it to an audio alarm when I find the time.

/Hampus

[r.furborough]

I think you will find one is the sender for the gauge, the other is just a switch for the low oil pressure alarm & lamp. If you also have a temperature gauge you will normally find the same set-up.

[Maddog]

Originally Posted by r.furborough

I think you will find one is the sender for the gauge, the other is just a switch for the low oil pressure alarm & lamp. If you also have a temperature gauge you will normally find the same set-up.

This is correct, you cannot run the gauge and an alarm off the same sender. They need to be seperate. On mine the oil senders are on a "T" fitting to seperate them. For the engine temp, there are (x2) .5" senders in different locations in the head. Hook up the alarms (audible), as well as the gauges. Don't ask me why I know this.

[shakey doug]

Alan,
As previously posted the other sender is a light circuit To use as a alarm circuit use a low current [milliamps] draw piezo type siren as supplied by tandy, there will be no need to use a relay system with this type of siren. To test sender use a multimeter or probe light while granking or running engine to confirm correct operation an alarm ciruit can be set up to incorparate a light and isolating switch.

Shakey.