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Discussion Starter #201
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I cut into the front clip to help with clearance, I also am going to be using hood pins instead of the good latch so that’s out of there. My PS cooler is on a thermal switch so we will see if it ever kicks on.
 

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Discussion Starter #203
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Got all 4 of the old shock mounts off. Cleaned it all up and re painted. But I don’t think I want to put the new ones on yet until the body is on. The new mounts are home made but modled after James duff dual mounts.
 

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Discussion Starter #204
Someone might laugh at me for this but I need help. I’m trying to get the oil pressure gauge hooked up so that I can test run this engine longer and be confident that I have oil for it. Problem I’m having is every time I hook up the ignition wire it peggs out the gauge. The way I have it wired is one wire to the sending unit which is just a single post. And I have a positive and a ground going right to the battery. I have tried two different gauges and they both max out as soon as I hook up the power wire.
 

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1964 Chevy C10, Cummins ISB170, Allison 1000 5 speed, full float 9”, ECU Tune, 5/7” static drop
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Someone might laugh at me for this but I need help. I’m trying to get the oil pressure gauge hooked up so that I can test run this engine longer and be confident that I have oil for it. Problem I’m having is every time I hook up the ignition wire it peggs out the gauge. The way I have it wired is one wire to the sending unit which is just a single post. And I have a positive and a ground going right to the battery. I have tried two different gauges and they both max out as soon as I hook up the power wire.
The sensor is the ground connection. You should only need a positive and the sensor wire. Have you taken an ohmic read from the sensor post to the engine block with the oil sensor wire off the post, this will see if the sending unit is good.
 

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Blaster,

Nice build. You still in Utah? And I'll second Fxsu... You should have the positive hooked up to one side of the gauge - the other connection on the gauge goes to the sensor.

Cj
 

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You might also get the same result if your "pressure sensor" is actually an oil pressure switch - The oil pressure switch is a direct short to ground at zero PSI oil pressure.

QUICK EDIT: Most electric oil pressure gauges are 3 terminal devices
+12 Volts
Ground
S - wire to the sender
 

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Discussion Starter #208
Blaster,

Nice build. You still in Utah? And I'll second Fxsu... You should have the positive hooked up to one side of the gauge - the other connection on the gauge goes to the sensor.

Cj
Yup still in Utah, two of my brothers also have bronco’s.
 

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Discussion Starter #209
You might also get the same result if your "pressure sensor" is actually an oil pressure switch - The oil pressure switch is a direct short to ground at zero PSI oil pressure.

QUICK EDIT: Most electric oil pressure gauges are 3 terminal devices
+12 Volts
Ground
S - wire to the sender
Yes these gauges I have are that way. But I don’t have ground straps or anything hooked up. So this basically is like starting the engine on a stand. The battery is on the floor. But I’m not sure if it’s a sender or switch like you say. This was a generator motor.
 

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... But I’m not sure if it’s a sender or switch like you say...
The electric oil pressure gauge MUST be used with a sender that has a matching resistance range. A quick Google search returned a few resistance ranges.
240 to 33 ohms
0 to 90 ohms
73 to 10 ohms
0 to 30 ohms
16 to 158 ohms
There are others - NOTE: Some resistance ranges are reversed from the others.

RECOMMENDATIONS:

1. If you have the oil pressure sender that came with the electric oil pressure gauge, install it on the engine.

or

2. Buy a mechanical oil pressure gauge and install it (no electrical gremlins)
 

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Discussion Starter #211
The electric oil pressure gauge MUST be used with a sender that has a matching resistance range. A quick Google search returned a few resistance ranges.
240 to 33 ohms
0 to 90 ohms
73 to 10 ohms
0 to 30 ohms
16 to 158 ohms
There are others - NOTE: Some resistance ranges are reversed from the others.

RECOMMENDATIONS:

1. If you have the oil pressure sender that came with the electric oil pressure gauge, install it on the engine.

or

2. Buy a mechanical oil pressure gauge and install it (no electrical gremlins)
Makes me wonder what a stock bronco range is. I also wonder if I can take the oil pressure sending unit off my old 302. If the treads are the same.
 

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Discussion Starter #212
It actually looks like the only difference might be 1/8 inch NPT to 1/4 NPT. And I’ve been entertaining the idea of putting some sort of T adapter in there so that I can run a mechanical gauge as well as the electrical gauge.
127392
 

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4bts sometimes came with both a pressure sender and a switch. Fairly common on industrial applications but was also found on engines in the delivery vans. Typically, the sender was located on the passenger's side of the block and the switch was over on the oil filter plate. However, my industrial 4bt manual shows a switch on the driver's side. Threads are listed as 1/8 x 27 NPTF.
 

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Discussion Starter #214
4bts sometimes came with both a pressure sender and a switch. Fairly common on industrial applications but was also found on engines in the delivery vans. Typically, the sender was located on the passenger's side of the block and the switch was over on the oil filter plate. However, my industrial 4bt manual shows a switch on the driver's side. Threads are listed as 1/8 x 27 NPTF.
So I don't have another one on the passenger side. This one on the right in that pic came from the driver side but I couldn't see a part number on it. The on on the left is the original bronco sender. So I was thinking I will adapt it to work so I can use the stock oil gauge for the bronco. But it may also be a good idea to have a mechanical gauge pod.
 

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Discussion Starter #215
Well, I adapted the bronco pressure sending unit. It jumped up to 70 and then was bouncing around 100. So I picked up a $20 gauge from AutoZone that is mechanical and this is what it tells me.
127399
 

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In general, the 4bt is very efficient in the heat department. Big radiators and cooling fans are generally not needed. Unless you live in a very hot area or really stress the engine you may never have the cooling fan turn on with that 4 core radiator. In winter months it's sometimes a chore to get it up to temp to warm up the heater. One fan that was popular years back was a 2 speed unit from a '97-98 Lincoln Mk8. Those were only 2225 CFM and one guy commented that when it turned on it knocked the squirrels out of the trees.
 

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Discussion Starter #218
So I have a few questions about how my engine is running. At some point I will bring it to a shop and have it timed properly and maybe have these issues addressed. So first I noticed that when I start this motor it will run for a while then all on its own the RPM's will noticeably increase and will stay elevated. But I don't have the KSB wired up. Second is another RPM issue. If I throttle up, when I let off the RPM's don't come all the way down. Last I tried to kill the engine with the fuel shut off lever on the side of the pump, nothing happened.
 

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Has the fuel screw been adjusted on this pump? Sounds like you may be getting close to the run away point and need to back off on the fuel screw. If it should run away the only way to stop it would be cut off the air supply to the engine. Could get very scary.
 

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Discussion Starter #220
Has the fuel screw been adjusted on this pump? Sounds like you may be getting close to the run away point and need to back off on the fuel screw. If it should run away the only way to stop it would be cut off the air supply to the engine. Could get very scary.
Not that I know of. I upgraded the fuel pin and spring but I haven't done anything other than lower the idle bolt on the outside. This was a supposedly rebuilt pump off ebay. After I bump the throttle and it stays up a little if I shit the engine off and restart it, its back to normal.
 
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