60Patrol

Well, while you all jacked my thread and chit-chatted the day away, I made some more progress on the project:

1) Operational clutch: check.
2) Operational starter: check.
3) Brakes: Check
4) Exhaust: Check
5) Working hand parking brake: check
6) Working marker lights and turn signals: check
7) Windshield: check
8) Headlights and High Beams: check
9) Engine runs... CHECK:

Robert, you are an animal. That sounded really good! Started right up. Pro job.

So what should we talk about next.

Looking and sounding great, Robert! Great video!

Well, the weekend left me with a Patrol that starts, revs, and idles... I dropped it in gear and confirmed that the speedo works, but the multi-gauge gave me fits.

Fuel gauge worked, oil gauge registered nada (I have to figure out if it's the guage or the sender, because my mechanical shop pressure gauge says the truck is making 40psi at idle, and 60+ under revs)

Temp gauge worked in reverse (as Faux40 and others have noted before- It spikes from 0 to 212 when power is applied, and then drops down to about the 3/4 mark as the engine warms up... then back to zero when the truck is turned off

My shop temp gauge says the truck never climbed above the 160 degree thermostat ( not bad considering I ran it for nearly an hour while I set the timing and idle, on a hot 105 degree Arizona day... )

When comparing to my 62 Patrol, I did notice that the gauge on that truck (which has screw post connectors on the back) sits at 212 when the truck is off, then drops to zero when you apply 12v. The gauges (and wiring harness) on this truck (both of which came from the red Patrol donor) must be the later style- it uses spade connectors, and the temp sits at 0 when off, and jumps to 212 when you apply 12v.

hmmm, I think that when this truck was green, that it used an earlier gauge with the post connectors as well ...

Maybe that voltage regulator that is used with the dash on 68-later Patrols is a voltage inverter that feeds the temp gauge -12 volts?

But I don't have any "extra" unused wires in the dash harness that would imply that I'm missing some component behind the dash and I don't recall the red Patrol ever registering hot on the temp gauge back when I used to drive it...

Might also be a bad ground- I do recall that the dash cluster is only grounded via the 4 screws that attach it to the firewall- maybe I'll add a jumper wire to give it a better ground

I'll figure it out.. should be pretty basic Ohm's law stuff. Just add time, voltmeter, and aggravation...

The gauge regulator the late model does feed the fuel and temp gauges. When my wasn't working the gauge had no voltage, obviously. I finally tweeked it and got it to work. It uses a bitmetallic arm wrapped with thin wire so that the points open and close as the arm is heated by the coil of wire around it. I adjusted the timing of mine to get about a 60% -70% close time; aiming for an average of about 9 volts. I think the purpose of the regulator was to prevent the gauges from tracking the voltage off the alternator which varies up to 13 or more volts depending on engine speed. It is a very simple device but I don't see how it could invert the voltage (it just switches the 12 volt on and off). Its just a set of contacts that open and close. When applying full voltage you are probably over driving the gauge. ??

Incidentally, the fuel gauge on the newer Patrol is way different than the old one. It also uses a simple bimetallic arm to show fuel level as opposed to some mechanism involving a coil.



Why nine volts? Well there was a Datsun site I found that made that recommendation. Interestingly, they also had a solution for building a simple regulator from IC chips, which should be right down your alley, if it turns out that is what you need. I had purchase those chips but never used them. They may still be lying around somewhere.

So, OCD can sometimes be a challenging companion to go through life with...

I spent all day yesterday trying to get some work done, while the back of my brain stewed about my Patrol gauge dilemma... After reading Plateaucal's very informative post about the regulator, I decided that wasn't related to my issue...

As soon as I found a breaking point from work at about 4pm, I changed into my grubby clothes, and went out into the heat to start tearing gauges apart...

The oil gauge was simple- it was the sender- I swapped in a different one, and it started reading oil pressure.

for the temp gauge, I was flummoxed... I have 2 early-style temp gauges, and both of them peg to the high side when they are off, and I have 2 later-style temp gauges, and both of them peg to the low side when they are off. I searched through images on the forum, and old brochure pics, and yup.... that's how they are supposed to be.

Then I re-ran my harness, looking for any trace of the leads for a 68- later gauge regulator, but nope- nada. I hooked up one of my older temp gauges to the Patrol, to test the temp sender, and when I powered up the truck, the needle dropped to 0, then climbed as the engine warmed up, just as I expected. If I could have simply screwed the early style temp guage into the later style cluster housing, I would have been DONE at that point, but naturally, the gauges only fit in the cluster that they were originally designed for

So, I sat there and stared at it, thinking to myself "This would be working just FINE, if I only had a later style temp gauge that defaulted to the high side when the truck was off..."

and then it hit me- the oil gauge defaults to 0 when the truck is off. if I took an oil gauge, and flipped it over to the other side of the cluster, it would be "upside down", so the needle would default to the top when the truck was off, and the tick marks would be right in the same location as they are with the temp gauge... Could it really be THAT easy...????

so I started checking impedance.. and wouldn't you know it: The oil gauge and the temp gauge, and both senders are all IDENTICAL, 36-38 ohm impedance when cold, and about 60 ohms when activated... (remember I'm using the early style senders that were already on this truck when it was green- not sure if later senders will have different impedance values)..

so, I went back into my spare parts looking for another later-style oil pressure gauge, and YES- I had 2 of them, which emboldened me to make one of them my sacrificial lamb in the next phase of this little experiment...

VOILA... when I hooked up the "oil pressure, turned temperature gauge" and fired up the truck, the needle dropped to 0, then tracked up the scale right along with my shop temp gauge as the truck warmed up.... it behaved exactly like the older-style temp guage

so, I removed the little "psi" label from it, and added an 'F', and bolted it into the cluster... in the truck, it looks like a "correct" early style gauge cluster, but more importantly, everything works...

Some of you will probably think this is the biggest hack of all time, while others will be wondering why I would stay up past midnight on a Monday, just to fiddle around with gauges...

But me- I'm just glad to have a fully-functional cluster, which allowed me to finally bolt the gauge panel into the truck....

side note- even though my issue wasn't related to grounding, I did add a ground jumper from the gauge panel to the firewall, and it did have the benefit of making my gauge backlights shine a little brighter.

also- check out my turn signal and high beam indicator lights- those are Dorman LED indicators that I found online. I think they look very similar to the originals, (aside from the one being red instead of orange), and they work great.

oh wait, I almost forgot:

1) Operational clutch: check.
2) Operational starter: check.
3) Brakes: Check
4) Exhaust: Check
5) Working hand parking brake: check
6) Working marker lights and turn signals: check
7) Windshield: check
8) Headlights and High Beams: check
9) Engine runs: check:
10) WORKING GAUGES: CHECK (woo-hoo )

Good job on those gauges! I enjoy those kind of projects. Much more fun than sanding,etc.
Do you happen to have the Dorman part numbers for the indicator lights? Mine look very scuzzy.
Also, looking at your cluster, I’m reminded that the fuel level gauge on our Patrols read Full to the left and Empty to the right. This is hard on my old brain.
Mild Bill

very nice dash and gauges...

Flaggoni wrote: Do you happen to have the Dorman part numbers for the indicator lights? Mine look very scuzzy.

Hi Bill- Here you go:

red: Dorman - Conduct-Tite 84926
green: Dorman - Conduct-Tite 84928

since these are LED, you will need to add a ground wire for each one, but the 12v positive lead can be connected right to the factory wires that power the OEM indicators