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Hello all. I am new here I have an 86 F150 with a 300 i6 “With” EEC iv. I read a similar thread that was informative and had helpful folks, but I still have a few questions. PO had vaccums lines looped, cut, or running to nowhere. I am waiting on an hei distributor, and cleaning up the engine bay in the meantime. Will my carb work with the “new” setup. And what needs to be capped and plugged where.
Thanks for the photos, it helps.
I had a fresh overhaul carb, my hot air choke tubes were in good shape and working as they should. I also did a lot of testing and decided I would not get an increase in gas mileage, so I never did change it out. It wasn't cost effective for me. Do you have a C6 auto transmission?
Others on this site have different results, opinions will vary.
One thing that's important is that this is a 2 step process. The carb is step 2. Get it running and drive it a little before you decide to buy a new carb.
If your hot air choke tubes are missing or not connected to the manifold, you might misdiagnosed a carb problem, when it's really a choke problem.
Good luck, Jim
I agree on the 2 step process. I also see the EGR valve is missing. Isn't that what covers those two large square holes under the carb? That will need to be addressed before it will run. Put the EGR back on with a block-off gasket or make a plate to cover those holes with a gasket.
Scope out your original coil. You should have a white/lightblue wire going to the coil. Take this wire and cut it, and extend it so it will reach the new distributor, that will be the power for your new HEI.
I have found if you find the computer under the dash, unplug it, and take the large wiring plug and turn it sideways and push it through the hole, you can take everything that is connected to this plug out of the engine compartment. I have found this is the easiest way to get rid of the stuff you do not need. Anytime you come across a component connected to this wiring plug,, you can take it out and if it has a vacuum line to it, cap this line.
Thanks for the photos, it helps.
I had a fresh overhaul carb, my hot air choke tubes were in good shape and working as they should. I also did a lot of testing and decided I would not get an increase in gas mileage, so I never did change it out. It wasn't cost effective for me. Do you have a C6 auto transmission?
Others on this site have different results, opinions will vary.
One thing that's important is that this is a 2 step process. The carb is step 2. Get it running and drive it a little before you decide to buy a new carb.
If your hot air choke tubes are missing or not connected to the manifold, you might misdiagnosed a carb problem, when it's really a choke problem.
Good luck, Jim
Thanks for the reply Jim. I will hang on to that carb while I get everything sorted and if it runs well with it on, I’ll just keep it.
I agree on the 2 step process. I also see the EGR valve is missing. Isn't that what covers those two large square holes under the carb? That will need to be addressed before it will run. Put the EGR back on with a block-off gasket or make a plate to cover those holes with a gasket.
Scope out your original coil. You should have a white/lightblue wire going to the coil. Take this wire and cut it, and extend it so it will reach the new distributor, that will be the power for your new HEI.
I have found if you find the computer under the dash, unplug it, and take the large wiring plug and turn it sideways and push it through the hole, you can take everything that is connected to this plug out of the engine compartment. I have found this is the easiest way to get rid of the stuff you do not need. Anytime you come across a component connected to this wiring plug,, you can take it out and if it has a vacuum line to it, cap this line.
I will get a plate on that egr. What about the tubes coming off of it? One is just busted off, the other is coming from the bottom and into the exhaust? I can add pix. Found the coil and wire you mentioned, I have it marked and ready. Just waiting on my distributor to arrive.
In the above picture you will see a "3 in 1 out" wire spice at the top of the wire cutters.
The single fat wire out will be trace forward to power the new HEI distributor.
This splice has 3 wires in, pinkish resistor wire, start bypass, and the extra resistor wire bypass wire which doesn't show up on wiring diagrams.
If you remove the black tape, your truck should be the same, please add photos of the spice to help others that come after you doing the same swap.
Following the fat wire towards the engine is a connector. This connector has the wires for the oil pressure and water temp which you need to keep intact. You will either have 3 or 4 wires out of this connector, I had 4. You can see the 4th wire coiled up in the top of the photo, it was 12 volt "KEY ON" power wire I didn't need.
Unfortunately the fat wire drops in size as it passes through the connector, it would be better, for higher current carrying capacity, if it didn't.
The other connector in the photo feeds the tach, the side with the single green wire goes to the "tach connection" on your new HEI distributor
Ask if you have more questions.
Please post photos to help others that follow you in the journey.
Good luck, Jim
I will get a plate on that egr. What about the tubes coming off of it? One is just busted off, the other is coming from the bottom and into the exhaust? I can add pix. Found the coil and wire you mentioned, I have it marked and ready. Just waiting on my distributor to arrive.
So that tube from the exh. manifold dose not go up to the EGR plate?
There is 2 ways of going with this.
1st (and I think the hardest) is to remove the tubes from the fittings and fittings from the plate & manifold and screw in plugs.Think pipe plug worked but been a while since I did this.To get the fittings out I used a large socket and impac gun, came right out.
2nd (and the easy way) is to cut the tube leaving enough where you can pinch the end closed and bend it over to make sure it is sealed.
Dave ----
So that tube from the exh. manifold dose not go up to the EGR plate?
There is 2 ways of going with this.
1st (and I think the hardest) is to remove the tubes from the fittings and fittings from the plate & manifold and screw in plugs.Think pipe plug worked but been a while since I did this.To get the fittings out I used a large socket and impac gun, came right out.
2nd (and the easy way) is to cut the tube leaving enough where you can pinch the end closed and bend it over to make sure it is sealed.
Dave ----
i’ll probably start with the 2nd and do the 1st eventually. Yea it goes from the exh to the bottom of the egr. I need to get a plate on it like you said. So plug both sides?
In the above picture you will see a "3 in 1 out" wire spice at the top of the wire cutters.
The single fat wire out will be trace forward to power the new HEI distributor.
This splice has 3 wires in, pinkish resistor wire, start bypass, and the extra resistor wire bypass wire which doesn't show up on wiring diagrams.
If you remove the black tape, your truck should be the same, please add photos of the spice to help others that come after you doing the same swap.
Following the fat wire towards the engine is a connector. This connector has the wires for the oil pressure and water temp which you need to keep intact. You will either have 3 or 4 wires out of this connector, I had 4. You can see the 4th wire coiled up in the top of the photo, it was 12 volt "KEY ON" power wire I didn't need.
Unfortunately the fat wire drops in size as it passes through the connector, it would be better, for higher current carrying capacity, if it didn't.
The other connector in the photo feeds the tach, the side with the single green wire goes to the "tach connection" on your new HEI distributor
Ask if you have more questions.
Please post photos to help others that follow you in the journey.
Good luck, Jim
Wow. Thanks a whole bunch, I’m sure I’ll have more questions as I get further along. I did indeed find that 3 to 1, I’ll keep that plug intact and use the one that was fat as the HEI power
If that tube from the manifold to the EGR is not leaking you could leave it.
Just below it in the picture I see the air pump tube going down to the cat converter that dose not have a hose on it, no air pump?
You may get a exh leak on it if not now over time. so keep an eye on it.
On my truck I did not have an air pump or that tube to the cat so I did not have to deal with it.
I am also running EFI EXH manifolds and Y pipe so the EGR tube would not connect and I did not want to use EGR anyway.
The valve looks to be in place on mine as I did not know if I had to go thru smog, no I dont, so I left it just blocked it off.
Dave ----
In the above picture you will see a "3 in 1 out" wire spice at the top of the wire cutters.
The single fat wire out will be trace forward to power the new HEI distributor.
This splice has 3 wires in, pinkish resistor wire, start bypass, and the extra resistor wire bypass wire which doesn't show up on wiring diagrams.
If you remove the black tape, your truck should be the same, please add photos of the spice to help others that come after you doing the same swap.
Following the fat wire towards the engine is a connector. This connector has the wires for the oil pressure and water temp which you need to keep intact. You will either have 3 or 4 wires out of this connector, I had 4. You can see the 4th wire coiled up in the top of the photo, it was 12 volt "KEY ON" power wire I didn't need.
Unfortunately the fat wire drops in size as it passes through the connector, it would be better, for higher current carrying capacity, if it didn't.
The other connector in the photo feeds the tach, the side with the single green wire goes to the "tach connection" on your new HEI distributor
Ask if you have more questions.
Please post photos to help others that follow you in the journey.
Good luck, Jim
The single green wire to the tac comes here first, to this soldered? splice that was under some tape. Can I just take it from here and run it there? The others seem to just go into the conduit.
The single green wire to the tac comes here first, to this soldered? splice that was under some tape. Can I just take it from here and run it there? The others seem to just go into the conduit.
Yes you can just cut it at the splice point, hopefully this will be long enough to reach the new distributor connection.
I would have guessed this as a 1 in 2 out splice, with one green wire going to the coil negative and there other going to the ecm attached to the distributor. I don't know what that thing is on top of the steering column drive shaft. It looks like the green wire is connected to each end??? Maybe someone else will know what it is, but I don't think you need it going forward.
On my truck, all of HOT wires were spliced together, and then ran to the coil postitive and ecm power, and anything else that needed power. Was your truck the same? It felt pretty random and just sort of tossed together on the assembly line.
Glad you are making progress, the photo will help others that follow in your steps.
Jim
Yes you can just cut it at the splice point, hopefully this will be long enough to reach the new distributor connection.
I would have guessed this as a 1 in 2 out splice, with one green wire going to the coil negative and there other going to the ecm attached to the distributor. I don't know what that thing is on top of the steering column drive shaft. It looks like the green wire is connected to each end??? Maybe someone else will know what it is, but I don't think you need it going forward.
On my truck, all of HOT wires were spliced together, and then ran to the coil postitive and ecm power, and anything else that needed power. Was your truck the same? It felt pretty random and just sort of tossed together on the assembly line.
Glad you are making progress, the photo will help others that follow in your steps.
Jim
Yes, my Hots appear the same way. That three way splice connects to the blue and white wire that comes from one side of the old coil plug.
Yes you can just cut it at the splice point, hopefully this will be long enough to reach the new distributor connection.
I would have guessed this as a 1 in 2 out splice, with one green wire going to the coil negative and there other going to the ecm attached to the distributor. I don't know what that thing is on top of the steering column drive shaft. It looks like the green wire is connected to each end??? Maybe someone else will know what it is, but I don't think you need it going forward.
On my truck, all of HOT wires were spliced together, and then ran to the coil postitive and ecm power, and anything else that needed power. Was your truck the same? It felt pretty random and just sort of tossed together on the assembly line.
Glad you are making progress, the photo will help others that follow in your steps.
Jim
Thanks again for your help on this. For the new distributor, am I basing plug wire numbers off of where the vacuum advance is, to where the plug for the old one is? I have them all numbered on the old one.
I agree on the 2 step process. I also see the EGR valve is missing. Isn't that what covers those two large square holes under the carb? That will need to be addressed before it will run. Put the EGR back on with a block-off gasket or make a plate to cover those holes with a gasket.
Scope out your original coil. You should have a white/lightblue wire going to the coil. Take this wire and cut it, and extend it so it will reach the new distributor, that will be the power for your new HEI.
I have found if you find the computer under the dash, unplug it, and take the large wiring plug and turn it sideways and push it through the hole, you can take everything that is connected to this plug out of the engine compartment. I have found this is the easiest way to get rid of the stuff you do not need. Anytime you come across a component connected to this wiring plug,, you can take it out and if it has a vacuum line to it, cap this line.
What would be the difference between using the fat wire from the 3 wire splice as Jim suggested, rather than the blue and white?
