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- #101
He’s alive. Just need to polish up the wire harness and then do the cooling system 
Build 12HT into a 55
- Thread starter CenTXFJ60
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- Thread starter
- #102
Hey Pat @dogfishlake , when you get a chance could you help me identify which wire on the 55 harness connects to the temp sending unit on the 2F motor? Thanks. Jimmy
Yep. Will go look shortly.
Ok, so this may only be half-arsed helpful but the wire on the sender is either a tan color or off white and I don't see an identifier stripe on it (first pic).
The second picture is where the harness comes out of the firewall. I can't tell if it is connected to the yellow with green marker or the yellow with black marker.
The second picture is where the harness comes out of the firewall. I can't tell if it is connected to the yellow with green marker or the yellow with black marker.
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- #105
This should help Pat. Was out all day yesterday but should have some barn time today .
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- #106
So our harnesses are a bit different. This being a 73 does not have as many wires as you show on that pigtail. Does not have the clip either
If you hook up a test light clip to your ground and check the leads you suspect are for your temp sending unit and have someone watch the gauge with the key on it should be pretty quick to narrow it down.
The bulb in your test light should have enough resistance to move your gauge.
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- #108
This is a great suggestion. So I’m a bit ignorant on electrical testing etc. I don’t have a test light (will get one). However I do have a multimeter that I use to check current and to ohm a wire etc.
I will follow your directions and see what I get. At the airport heading out for work, but will be back in the barn on Saturday. Thanks again. Jimmy
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- #109
So a few updates...I pulled the tank and it was in great shape. The rubber filler neck hose was dried and cracked. Found a 60 degree 2 1/4” and made it work. Also, swapped in a new Bosh primer. Now the motor pulls the fuel through and we are free of leaks.
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- #110
And a huge call out to Pat @dogfishlake. He donated a 55 radiator core and helped by getting it to and from a local radiator shop for rebuild. Then the packaging job was the best I’ve ever experienced. I could keep going on and an, but every experience I’ve had with Pat is this way. We are fortunate to have folks like Pat in this business
Thanks buddy. It is like @Pigeaten said to me when he GAVE me the trim for my 55 roof, "one big family here".And a huge call out to Pat @dogfishlake. He donated a 55 radiator core and helped by getting it to and from a local radiator shop for rebuild. Then the packaging job was the best I’ve ever experienced. I could keep going on and an, but every experience I’ve had with Pat is this way. We are fortunate to have folks like Pat in this business
I'm enjoying the build and learning from it so I am way happy to help.
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- #112
Dropped the radiator off at a local shop so the inlet and outlet can be modified. The bottom inlet needs to be moved out as far as possible on the passenger side and a 45 degree added. The outlet needs to be swapped to the passenger side as well. If you don’t run AC then it can be left as is and flip the thermostat housing. This was an oversight on my part and if I’d had figured it out earlier could have been done at the same time Pat had it rebuilt. So always learning along the way .
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- #113
Got the VSV working tonight. Will clean up all the vacuum lines with new ones etc. just getting it to function and will tidy things up.
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- #114
This video was for the owner of the truck. The first one I sent him the cold idle relay was engaged. That’s why I’m explaining how I bypassed it.
What was your source for new filler neck hose?
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- #116
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- #117
Had to re-work the inlet and outlet to accommodate the 12HT. Should have realized this and had it done while Pat had it rebuilt up north. Regardless, came out great and the stock 12HT hoses work with the stock 55 radiator. This video is a bit long as it’s an update I’m sending to Parrish who owns this truck.
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- #118
Oil and fuel gauges work. Temp gauge does not. I followed the 3 tests in the service manual and the OHM test failed. Should hit 25 and the highest I got was mid teens. Will post pics tomorrow, but looking for a good electric gauge to replace the mechanical aftermarket one already installed. I’d use it but the probe is huge and interferes with the thermostat if installed in the OEM location. Therefore I’d like to go electric.
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- #119
Was able to get the mechanical gauge to work. Ran the truck for 40 min and hit 160 degrees. Gonna see if I can find a possible mounting location for the diesel tach.
