Hi, I got my D100 with a slant 6 and 3 on the tree. Happy as can be. I am dialing everything in and am having trouble with the temp gauge not working.
I grounded the wire after disconnecting from the sensor and the gauge goes to the mid-point which I think means that it is working correctly. I put a new TS17 sensor in with a 1/4" to 1/8" brass bushing and even added an extra ground from the sensor to the body, but it is not registering on the gauge. I put the sensor in almost boiling water and it did register. Does this mean that I need a sensor with a different resistance?
This is what I have from the engine:
Casting: 2463420-11
Engine Id: TT 22 3 07 2
I will be pulling the head in a week or so and get those numbers.
I have much anticipation for the enlightenment that I will receive.

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Cheers, Bill.
Smoke em if you got em.

if the old sensor did not require a bushing to get it to screw in, but the new one does,, that would be a flag to me that
the two sensors operate at different resistance levels.

I checked on the RockAuto site and they show the TS 17 sensor being compatible with a 1966 D100 and fitting slant motors from
1963 to 1987,, I do not believe that is correct. I would look for a sensor with the thread size of the one that you removed.

For the cast in block numbers'
are you sure it is not 2463430,, those show for the 61 to 67 model years and the 67 to 74 model years.
I could not find a 2463420.
at one time I knew of a site that decoded the stamped numbers, but I have not been able to relocate it.

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Doo Ron Ron and the Duke of Earl are friends of mine.....
https://www.youtube.com/watch?v=uX8Nj8ABEI8

Thanks for your reply. The block is actually 2463430-11, sorry. Th sensor I took out also did not register. I will test the difference between it and the TS17. Also, I replaced the thermostat with a Stant 45358 180 degree and I ran a new wire to the gauge with the same results of no movement from sensor, but half way with direct ground.

_________________
Cheers, Bill.
Smoke em if you got em.

Grounding the sensor wire should peg the gauge.

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Joshua

Could this then be an issue with the voltage supplied to the gauge?

_________________
Cheers, Bill.
Smoke em if you got em.

Most dash gauges on vintage vehicles operate on 5 volts. Typically there is a voltage reducer either on the back of the instrument panel or built within one of the gauges that does that function. When the voltage limiters fail, they typically fault to no voltage, or to full 12 volts. The full 12 volts will quickly fry the gauges that it is supplying power to. If it is a limiter issue, there are modern solid state limiters available.
Or it could be that one gauge has failed. To troubleshoot, a wiring diagram for your vehicle and a multimeter would be useful.

_________________
Doo Ron Ron and the Duke of Earl are friends of mine.....
https://www.youtube.com/watch?v=uX8Nj8ABEI8

Check your bulkhead wiring connectors on both sides of the firewall for corrosion. The sensor wires usually hold up well but the main power wires get corroded. Also check the wiring harness ground behind the dash. I can't remember specifically where it grounds on your truck but alot of mopars ground to the steering column. Also, make sure the braided ground cable from the firewall to the back of the head is still there and in good shape. If not just make a new one from some 12 ga. Wire. Lastly, make sure the wires are tight to the ammeter in the dash. All the current from the alternator goes through it. If if gets loose it can catch the cab on fire.

Joel

I will be checking all of the voltages and connectors as suggested as soon as I get the engine back together and the battery hooked up. I do have the WSM and a multimeter and have been testing other various connections and verifying wire sizing.
The intake manifold heat sink to exhaust manifold gasket was halfway gone with rust creating major leakage and the timing chain cover was leaking oil, so I pulled the radiator, harmonic balancer, etc apart to repair. Number 2 cylinder is low compression at 90, 1=100, 3-6=105, hope it is the valves, hence pulling the head. Is it interesting that the valve springs are green?
The casting number on the head is 2206035-2 which indicates 62-65 and is consistent with the TT engine ID indicating a 63 block. Does anyone know why the temp sensor hole would be 1/4" instead of 1/8"? Is there a part number for the 1/4” sensor?
All of the support here is much appreciated.

_________________
Cheers, Bill.
Smoke em if you got em.

Your getting the correct answers. I've had two of these trucks and have three /6 in the shop.

The TS17 is correct but, it doesn't use a bushing. I recheck the 63 engine tomorrow.
The voltage regulator for the gauges is in the fuel gauge and is tied to the temperature gauge.
Grounding will peg the gauge if it is good. "Midpoint" means bad regulator or ground. Is you fuel gauge working?
Bad ground on engine or instrument cluster will cause inaccurate readings.

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I'm going to attempt to fix this project and not make it any worse.

I did indeed need to add engine to cab, engine to frame, and frame to bed ground straps.
I’m a thinking that my 66 D100 head is from a 63 Dart or Valiant as they have a 1/4 npt sensor - SMP TS52 according to RockAuto. The gauge # 2507114 looks to be original. I don’t think that the TS52 and TS17 have the same resistance range based on a post from SlantSixDan http://www.slantsix.org/forum/viewtopic.php?t=27531 , so I have left the TS17 installed with a bushing.
The fuel gauge seems to be fairly accurate and the voltage regulator in the fuel gauge seems to be working, but may be a little high.
I built the Texas Instruments 7805 chip hack from AllPar https://www.allpar.com/history/mopar/electrical2.html and it is putting out a solid 5 vdc. This makes the gauge climb to the first hash with direct ground as opposed to halfway from the fuel gauge connection. Just for grins I hooked up a 9 volt battery and the gauge went full with direct ground. So my mad plan is to get a TI 7808 and see if 8 vdc will make it work. Otherwise I guess I will need to get a new gauge.
Please let me know if anyone has a madder plan and I will be glad to try and implement.

_________________
Cheers, Bill.
Smoke em if you got em.

So the great lapse in responding was all of the engine work that I did. I think that I spent way too much time painting, haha.
It is running great now! Attached is how it looks. Off to the far left are the headlight relays, thanks for the pre-made harness SlantSixDan.

_________________
Cheers, Bill.
Smoke em if you got em.

Yellow engines run better. Scientific fact!

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

looks great, does that truck have two firewall mounted master cylinders?

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Doo Ron Ron and the Duke of Earl are friends of mine.....
https://www.youtube.com/watch?v=uX8Nj8ABEI8

One for the brakes…one for the clutch.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

The mad plan worked!!! The needle is moving as the truck warms up into a reasonable position on the gauge. I have only driven it once, so it could still go kaput, haha.
Although along with the 8vdc chip I needed to open up the gauge and tweak the dielectric bracket with a pair of needle nose pliers. I probably just got lucky that I didn’t trash the gauge, but I always say that I would rather be lucky than good.

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Cheers, Bill.
Smoke em if you got em.