Engine Wiring

[JohnnyDeere]

Ok Gents,

I have reached the point of throwing a tantrum in my shop so I need help. First I tried putting the supplied Engine Oil pressure sensor (Platinum Gauges) in my BP 347 and the sensor is two large to allow me to thread it in, not the male portion but the actual sensor is too big and hit the block before I can get the threads in.....What should I replace it with?

Secondly where do the remaining wires go....I got the EFI harness hooked up pretty straight forwards, but what am I plugging into the.....

ELEC Send Unit harness
1. Water temp sensor? I am assuming the blue water temp wire?
2. Oil Pressure sensor? Same thing the Grey oil pressure wire?
3. All the grounds in this bundle what should I do with them as the directions state the threaded sensor is the ground?
4. Elec choke wire beige where does this go?

EFI Crank Bundle (not from blue print but the one that cam with the RF harness)
1. I connected the orange wire correctly to the coil
2. The purple TACH wire should that connect to the grey wire that is not connected to anything on the front of the engine below the distributer?
3. Speed sensor wires Green, Grey, what should these hook up to?

I would post pictures to make this much easier but that has stopped working all together and I don't need my blood pressure to go up any more.

Appreciate any help from you fine gentlemen.

[narly1]

I think I can help you re the oil pressure sensor to block fitment question.

It sounds like you need a Scott Drake C2OZ-9B339-C extender, you can get one from Summit.

Earl

[OSU Cowboy]

I had to do that on my own 347 ... not a big deal at all once you figure it out. I guess we can say that about a lot of things can't we?

[Pete&Scott]

Ok Gents,

I have reached the point of throwing a tantrum in my shop so I need help. First I tried putting the supplied Engine Oil pressure sensor (Platinum Gauges) in my BP 347 and the sensor is two large to allow me to thread it in, not the male portion but the actual sensor is too big and hit the block before I can get the threads in.....What should I replace it with? Get the Oil Sending Unit Extension fit for 1965-1973 FORD MUSTANG 260 289 302 351W. I found one on Amazon.

Secondly where do the remaining wires go....I got the EFI harness hooked up pretty straight forwards, but what am I plugging into the.....

ELEC Send Unit harness
1. Water temp sensor? I am assuming the blue water temp wire? Yes
2. Oil Pressure sensor? Same thing the Grey oil pressure wire? Yes
3. All the grounds in this bundle what should I do with them as the directions state the threaded sensor is the ground? I bundled all the grounds to a ring terminal and attached to a existing threaded hole on the rear of the intake manifold
4. Elec choke wire beige where does this go? I pulled that wire out of the bundle and used it to power my USB outlet I installed under the dash

EFI Crank Bundle (not from blue print but the one that cam with the RF harness)
1. I connected the orange wire correctly to the coil
2. The purple TACH wire should that connect to the grey wire that is not connected to anything on the front of the engine below the distributer? No it should attach to the negative side of the coil.

Speed sensor wires Green, Grey, what should these hook up to? For my autometer, the Green wire hooked up to the Speedometer and the gray wire goes to ground.

I would post pictures to make this much easier but that has stopped working all together and I don't need my blood pressure to go up any more.

Appreciate any help from you fine gentlemen.

See comments in line above.

[PMD24]

If BP supplied your 347 with a Holley Sniper2 EFI, along with a coil, take a look at post 196 in my build thread. There I detail each wire connection. Try the oil pressure sensor supplied with your gauges, not the one supplied by FFR, and it may screw right in. Mine did. Your water temp sensor should be installed by BP already and connected to the EFI.

I didn't use the grey tach wire near the distributor. I took the tach wire directly to coil (-). You can also feed your tach from the small 6 pin I/O harness of the EFI. Don't recall which wire, but it's labeled in your EFI documents provided by BP.

I didn't use the sending unit wires in the Ron Francis harness. Instead, I used the wiring and plug-in connectors provided with my Speedhut Vintage gauges, and tore out all of the wires associated with the RF sending harness. I'm not familiar with the gauges you mention but if they came with sensors and cables, you can use either, your decision. For me personally, it made more sense to use the wiring provided with the gauges.

If your speedo gauge uses GPS, you will not use the green and grey speedo wires. I repurposed those wires for a neutral safety switch in place of the clutch switch.

Take it one circuit at a time and ask questions here. Lots of help available.

Pat

[JohnnyDeere]

If BP supplied your 347 with a Holley Sniper2 EFI, along with a coil, take a look at post 196 in my build thread. There I detail each wire connection. Try the oil pressure sensor supplied with your gauges, not the one supplied by FFR, and it may screw right in. Mine did. Your water temp sensor should be installed by BP already and connected to the EFI.

I didn't use the grey tach wire near the distributor. I took the tach wire directly to coil (-). You can also feed your tach from the small 6 pin I/O harness of the EFI. Don't recall which wire, but it's labeled in your EFI documents provided by BP.

I didn't use the sending unit wires in the Ron Francis harness. Instead, I used the wiring and plug-in connectors provided with my Speedhut Vintage gauges, and tore out all of the wires associated with the RF sending harness. I'm not familiar with the gauges you mention but if they came with sensors and cables, you can use either, your decision. For me personally, it made more sense to use the wiring provided with the gauges.

If your speedo gauge uses GPS, you will not use the green and grey speedo wires. I repurposed those wires for a neutral safety switch in place of the clutch switch.

Take it one circuit at a time and ask questions here. Lots of help available.

Pat

Thanks Pat, I will take a look at your thread, my gauges are the base model from FFR so they did not come with any wiring I have to use the RF harness which is not a big deal….i am using the supplied sensors that came with the gauges I bought the extension just now from summit that was listed above thanks for that!

I again have not looked at your thread so when you say the water temp sensor was already installed by BP I am curious what I am looking at. I took the one supplied with my gauges and removed the plug in the engine thermostat housing and put the sensor there, if that’s wrong I guess I am totally lost.

[phileas_fogg]

Hey JohnnyDeere,

EFI gets its own water temperature sensor, which is almost certainly already installed (by BP) at the front of your intake manifold above the #5 cylinder. You need a second sensor for your water temp gauge, which is the one you've put in the thermostat housing. Many folks will tell you that the t-stat housing isn't the optimal place, because if the t-stat fails, your gauge won't register temperature accurately. However, lots of folks use the t-stat port, including me. You just have to make sure to look at the gauge about 5 minutes after start to make sure the gauge is showing the temperature come up. If you don't see the gauge going up, you know you've got an issue (and need to abort your drive).


John

[JohnnyDeere]

See comments in line above.

Excellent guys!!! huge help, with the green wire speed I do have that connected to my speedometer just wondering where the other end of it is connected to? It runs into the engine bay with the other wires but not sure if there is a sensor or what. Also what about the EFI-Crank wire which is also in the small bundle of wires.

I knew you guys would get me out of trouble.

[JohnnyDeere]

Yes I should have clarified these sensors are for the gauges

[PMD24]

Johnny,

Here's a photo of the water temp sensor that BP installed for the EFI. I've pulled the connector plug off the top to move it to the other port shown in the photo. You won't need to move it unless you have a heater. Not sure what engine you're dealing with but these are the only water two ports on a 302 based engine.

Coolant ports 1 lr.jpg

Regarding the t-stat port, I agree with everything John said. T-stat port isn't ideal, but ok for a gauge if you don't have other ports. Some folks install a T in the port above where I mentioned the heater would connect, and re-install the sensor in the T, or put the gauge sensor there. That's not ideal either because if the heater valve is closed there would be no flow though the T, so readings wouldn't be reliable.

Good to hear you're making progress.

Pat

[JohnnyDeere]

Made some good progress today based on everyone's help. Only a few wires left that I have questions on,

1. Light Blue- EFI Crank wire? What does this hook up to?
2. Green - Thermo Fan SW wire?

Thanks again guys.

[PMD24]

Still don't know if your 347 was supplied with the Sniper 2 EFI, but if so, the Crank wire is not used, and the green fan wire gets connected to the black with yellow stripe wire coming out of the 6-pin I/O harness of the Sniper harness. That allows the Sniper to control your fan. The green fan wire up near the radiator is not used. It's a second lead off the same fan wire. Cut and cap.

If you do have the Sniper and connect the black/yellow for fan control.... WARNING - do not start the engine until you have done the setup wizard and turned on Fan 1 and set the on/off temperatures. If you don't do this, the fan will not come on and the engine will overheat.

You'll want to unplug your fuel pump while messing with the setup using the handheld screen. That way you aren't pumping any fuel while going through the setup.

Pat

[phileas_fogg]

Pat nailed it.

A little more information for those that find this thread later:

The light blue EFI CRANK is hot only when the key is in the START position; I am not aware of any Holley EFI system that uses EFI CRANK (there may be one, so read your EFI documentation!).

The fan comes on when the green fan wire is connected to ground. Most EFI computers have a control wire for the fan, and most of those control wires go to ground when the computer wants the fan to come on. Again, read the EFI documentation to verify that its fan control goes to ground. If so, connecting the Ron Francis green wire to the EFI fan control wire allows the EFI computer to control your fan.



John

[JohnnyDeere]

Pat nailed it.

A little more information for those that find this thread later:

The light blue EFI CRANK is hot only when the key is in the START position; I am not aware of any Holley EFI system that uses EFI CRANK (there may be one, so read your EFI documentation!).

The fan comes on when the green fan wire is connected to ground. Most EFI computers have a control wire for the fan, and most of those control wires go to ground when the computer wants the fan to come on. Again, read the EFI documentation to verify that its fan control goes to ground. If so, connecting the Ron Francis green wire to the EFI fan control wire allows the EFI computer to control your fan.



John

Thanks Pat and John!

I have enjoyed this process very much but the wiring has not been my Jam. I just hope that when the time comes there is not blue smoke…..

[JohnnyDeere]

I am sheepishly back again.....I am stuck on the Speedo, I have the TKX transmission and I found that it has the electronic Speed sensor already installed and I found conveniently a plug from the wiring harness right there and mated the two (they do say speed sensor on the green and grey wires going into the plug)....I assumed that was easy, but now I am holding the mechanical speed sensor in my hand from factory five and looking at the directions and am lost. My speedo gauge (AutoMeter Platinum) says its designed to work with an electrical speed sender so do I not need the mechanical sender that came with the kit? and assume my original harness plug into the already installed sensor is correct? Does this also void the need for the two additional wires green and grey that say speed sensor that were bundled with the EFI-Crank wire?

Thanks again gents...you are making the process possible.

[Papa]

Looking at the new TKX, it looks like there is a built-in electronic speed sender that may work with your gauge.



I also found this post from Paul that may help: https://thefactoryfiveforum.com/show...l=1#post523560

You may need to find the proper plug if your gauges didn't come with one, and you'll need a cover for the mechanical speedo port.

[PMD24]

I'm not familiar with your gauges but the grey and green e-speed wires from the connection on the PS of the TKX run through the rear harness to behind the dash. There they connect to the dash harness. In the dash harness you will find the same grey and green wires available to connect to your speedometer, if your speedometer uses that type of source.

The FFR mechanical speed sensor isn't used unless your speedometer is of the type that uses that format (unlikely). The connection point for that sensor is on the DS of the TKX and will be covered with a small plate and one bolt.

If your speedo is GPS based you won't use the mechanical or the e-speedo.


Pat