Help...wires on my 425 ripped by a stick

[Homebrew]

I was brush cutting in the woods, backed up and a large stick wedged up into the engine compartment and pulled apart some wires. The PT immediately stopped and I got nothing when I turned the key. After I got the stick removed, I saw that a connector had been pulled apart as well as a wire to the fan and perhaps another wire. Got the connector back together and it started and got it back to the garage. I know where the fan wire goes....I turned the key on and touched this wire to the connector and the fan started. THe problem is that it looks like there's an additional wire with a connector on it that I can't figure out where it goes. Maybe it goes to the taped wire in the picture. Anyone know if this wire is supposed to be connected to anything or is for diagnostic purposes? The picture shows arrows to the two wires in question (the one with a connector and one taped up). It sure doesn't look like the one with the connector pulled out of the one with the tape.

[MossRoad]

I have a few extra wires on my Kohler. Perhaps you have some on your Robin?

[Tim_in_CT]

On my PT 422, in the back right corner there is a wire bundle (with the fan connector, ignition switch ground wire?) , which also had an extra connector which is wired to the pressure switch on the engine. I suspect that it is the same on your engine. Check for continuity with ground with the engine stopped (should be zero resistance) and running (should be infinite).

Apparently the robin engine comes with a wiring harness, but the wire from the pressure sensor is not used by Power Trac. That spare connector is now wired to a Sonalert alarm buzzer, which should be a stock arrangement, IMHO.

[BobRip]

Originally Posted by Tim_in_CT

On my PT 422, in the back right corner there is a wire bundle (with the fan connector, ignition switch ground wire?) , which also had an extra connector which is wired to the pressure switch on the engine. I suspect that it is the same on your engine. Check for continuity with ground with the engine stopped (should be zero resistance) and running (should be infinite).

Apparently the robin engine comes with a wiring harness, but the wire from the pressure sensor is not used by Power Trac. That spare connector is now wired to a Sonalert alarm buzzer, which should be a stock arrangement, IMHO.

Tim, I did the same thing but also added a light. So at low oil pressure or engine stopped I get a Sona alert and a light on the dashboard. This wire was originally not connect on mine either. A 422 of course. You can trace this back to the engine mounted oil pressure sensor.

[Tim_in_CT]

Assuming you have the 25HP Robin engine, it probably has the same wiring arrangement. You can look in the service manual (pg 44) at Robin Suburu, which has the color coded wiring diagram. On my PT422, the oil pressure switch is a gray wire (Robin22 wiring diagram below).

Subaru Robin - Service and Support

I did the same thing as Bob... sonalert buzzer with a cut-out toggle switch and a warning light.

[TheBigHeadKid]

Tim

I'll have to agree... that should be standard equipment. Where did you get those gauges? What model ? ...etc

Is there a thread about your modification that I have missed?

The schematic you attached... I do not see where you tied in the Sonalert.
Dave

[Tim_in_CT]

On the upper right side of the schematic is the oil pressure switch. Power Trac doesn't connect anything to this gray wire... their is an unused bullet socket connector in the aft right side of the engine compartment.

I ran a wire from this to the sonalert, and another wire from the ignition switch to through a cut-off switch to the sonalert. I put a warning lamp wired around the buzzer/switch, so the light will always glow even if the buzzer is cut-out.

The oil pressure switch is grounded when it sees no pressure, and is open-circuited when the engine is running.

Some mention of it here:
http://www.tractorbynet.com/forums/p...x-cooling.html

I bought the gauges here (there were on sale atthe time for about $50 each):
R6859R - ISSPRO EV Marine - Red Pointers: Transmission Oil Temp. Gauges - Towing - egauges.com

I bought the sonalert buzzer from ebay for about $10. I don't remember the model number, but it isn't hard to figure out which one you want from mallory's website.

[cqaigy2]

Originally Posted by Tim_in_CT

On my PT422, the oil pressure switch is a gray wire (Robin22 wiring diagram below).

I did the same thing as Bob... sonalert buzzer with a cut-out toggle switch and a warning light.

Wow, nice job on the panel and schematic!!
Hm is seem to say wow a lot in this forum.

[J_J]

Tim,

Are the oil temp senders pretty standard? The reason I am asking, is how does one calibrate the oil temp sender to the receiver? Years ago, while working as a Navy electronics technician I made up a thermistor assembly hooked up to a meter and put the sensor in the dipstick tube, but you had to calibrate the meter for it to read accurately. One way to check for accuracy would be to use a calibrated temperature meter, put it in the oil or hydraulic fluid and compare, if it is not accurate enough, maybe a variable resister could be added to the circuit.

[ponytug]

Mostly they fall into a couple of standard types. In general, it isn't an issue because you are putting a ford diesel sender in a- gasp- ford diesel-, but around here it is a reasonable question.

Thermistors have also gotten better since then. If you buy a 10k, it is really 10k. I haven't calibrated a thermistor in decades.

All the best,

Peter

Originally Posted by J_J

Tim,

Are the oil temp senders pretty standard? The reason I am asking, is how does one calibrate the oil temp sender to the receiver? Years ago, while working as a Navy electronics technician I made up a thermistor assembly hooked up to a meter and put the sensor in the dipstick tube, but you had to calibrate the meter for it to read accurately. One way to check for accuracy would be to use a calibrated temperature meter, put it in the oil or hydraulic fluid and compare, if it is not accurate enough, maybe a variable resister could be added to the circuit.