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Just a quick pic of the installation.

 

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Right now I just have a short hose going from one outlet to the other.

As far as hot spots. There are two kinds of heat valves. One just closes in one or the other lines to the core. The other is a double valve that sends the flow back to the engine. I have the latter on my DD 90' Bronco because of hot spots you mention. (I suspect you know all this) The other style valve is on the older Broncos. (Like 70's)

Years ago, I asked on this forum which style should be used on the 4BT. I was told by several people that just a shut off is all you need. (No need to flow) While I have the loop right now, I will be installing the heat system shortly with an old style valve. I know that a loop valve won't hurt the engine, I like the quality of the old style.

So, my question now is, have you something official that says I need to let it flow? Please let me know because I'm literally looking to do this in the next couple days.
It appears I was mistaken. Apparently a heater coolant loop is not necessary on the B series engine, as no mention of it was made in the installation guide and it was not shown as being necessary for engine dynamometer testing. It seems the internal bypass allows enough flow without the coolant loop. Now, having said that, a shutoff isn't necessary for warm weather operation. I run my engine in 115°+ ambient with a bypassed heater core loop which is restricted only by the 1/4" (or 3/16") hole specified in the install guide and the engine stays completely cool. So, the heater loop can be either shut off or bypassed it seems. In any case, make sure the fitting coming out of the head to the heater core has the restrictor in it.

Can you quote the B series manual?
You mean the Install Guide? Bob S. has it in the Technical Topics sticky under Installation Considerations. The pertinent posts start here. That said, they are jpegs that are of a fairly low resolution, rendering some of the smaller print in some of the images unreadable. For a limited time only, I will offer my personal higher resolution pdf of the guide for download here. Maybe Bob will see it, download it, and use it to replace the low-res jpegs.
 

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1k ohm is too much resistance to excite the field. 500 ohm is much more reliable. Unless you have a reversion problem.

A 2 amp diode can be used instead of a resistor or light. It's by far the best method if you don't have a light. As it full fields the alt on start and prevents reversion.

Nominal pulley ratio on a 4bt outfit is 2.8. Which means that the alt is spinning at 2.8x the crankshaft speed.

The 22si is a workhorse. It's a mature design that is dialed & parts for it are cheap. CS-144 is basically the same alt but it's regulator is meant to be driven by a PWM signal from a computer. The 22si regulator is old school linear.

22si use conventional diodes where as the CS-144 uses avalanche diodes.
 

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So, the heater loop can be either shut off or bypassed it seems. In any case, make sure the fitting coming out of the head to the heater core has the restrictor in it.
Reading the guide, it appears the restrictor is so the pressure in the heater core doesn't get too high. Kind of strange, but who am I to judge? My next thought is do I have one? is it just a washer with a hole in it welded to bottom of the fitting? If I pull the top hose and look down the fitting, will I see it easy? Why wouldn't mine have one stock?
 

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is it just a washer with a hole in it welded to bottom of the fitting? If I pull the top hose and look down the fitting, will I see it easy? Why wouldn't mine have one stock?
On my '85 it was plastic washer about 1/8" thick. It is not attached to the fitting just trapped by it and rests on the bottom of the hole.
 

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Reading the guide, it appears the restrictor is so the pressure in the heater core doesn't get too high. Kind of strange, but who am I to judge? My next thought is do I have one? is it just a washer with a hole in it welded to bottom of the fitting? If I pull the top hose and look down the fitting, will I see it easy? Why wouldn't mine have one stock?
Heater cores can't handle the pressure that the water pump can generate at high RPM. If you pull the hose, the restriction should be visible. I don't recall what my engine originally had. Right now it has an aluminum -10 male AN to pipe fitting screwed into the head for the heater supply. I machined a piece of aluminum bar stock to press into the fitting and then I drilled a 1/4" (or maybe 3/16"?) hole through it to give the needed restriction. My heater returns to the bung on the supply side tank on the radiator, same as it did with the original gas engine. I chose to keep the heater return going to the radiator tank because it does a much easier, faster job of eliminating air trapped in the system.

Anyway, I've peeked into the tank while the engine was running and the water level was low enough that the heater return was uncovered. At idle, plenty of coolant flows through the circuit. Rev the engine to 2000 RPM and water flat blasts out of there. There is definitely a lot of pressure in the block when the engine is running at speed.
 
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