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Help with wiring

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Dk46

Help with wiring

I have started with trying to straighten out the complete mess of cut, tangled, and spliced wire all over this bronco. I have the evtm and it is a life saver, believe me. Today’s question is this, the wiring from the fuse block that should be hot in acc or run is only hot in run. The key switch feels fine as it turns but no juice unless you go all the way to run. Again I really appreciate any and all help I can get.

Danny K
1982 Bronco
351W
Holley 600
Deleted EEC3

ArdWrknTrk

Re: Help with wiring

Administrator

Danny, you might try checking the ignition switch adjustment.

Gary has outlined the way you stick a pin through the switch, to lock it, and then retighten the nut holding it to the column.

But you say it won't work in ACCY, and that may be down to a broken actuator rod.
The rod might push the switch into run & start, but not pull it back.

Just stick your head under there and work the key back and forth to see what it is, or isn't doing.

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

Gary Lewis

Re: Help with wiring

Administrator

In reply to this post by Dk46

Danny - Jim has a point, it could be the adjustment of the ignition switch. You can see how to adjust it here: Electrical/Ignition and on the Ignition Switch tab. Or, it could be that the ignition switch itself is bad.

You can see from the diagram below that there is only one set of contacts in the switch that handles Accy, and those are the ones which feed Circuit 297, the black/light green hash wire. But we know that section of the switch is getting power or Circuit 32 wouldn't get power and the truck wouldn't start.

So you could try adjusting the ignition switch, but I fear that it is bad.

Gary, AKA "Gary fellow": Profile

Dad's: '81 F150 Ranger XLT 4x4: Down for restomod: Full-roller "stroked 351M" w/Trick Flow heads & intake, EEC-V SEFI/E4OD/3.50 gears w/Kevlar clutches
Blue: 2015 F150 Platinum 4x4 SuperCrew wearing Blue Jeans & sporting a 3.5L EB & Max Tow
Big Blue: 1985 F250HD 4x4: 460/ZF5/3.55's, D60 w/Ox locker & 10.25 Sterling/Trutrac, Blue Top & Borgeson, & EEC-V MAF/SEFI

Steve83

Re: Help with wiring

Banned User

In reply to this post by Dk46

Dk46 wrote

...the wiring from the fuse block that should be hot in acc or run is only hot in run.

Are you saying you get no change when you turn the key backward to ACC? Study this diagram, its caption, and the relevant links in it:

Dk46

Re: Help with wiring

Well after testing and adjusting its the switch itself . Now another question. Im gonna put the cut off valve for the a/c. Does it matter which heater hose i put the valve on?? Thanks

Danny K
1982 Bronco
351W
Holley 600
Deleted EEC3

Gary Lewis

Re: Help with wiring

Administrator

Glad you got it figured out.

As for the "cutoff valve for the A/C", I'm going to assume you mean you are installing a water shutoff valve in the heater hose line. Right? If so, then it doesn't matter which of the two hoses you put it in.

Gary, AKA "Gary fellow": Profile

ArdWrknTrk

Re: Help with wiring

Administrator

I'm going to assume low pressure cut out near the compressor.

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

Steve83

Re: Help with wiring

Banned User

In reply to this post by Dk46

Dk46 wrote

Does it matter which heater hose i put the valve on?

Functionally, no. Stopping the coolant in one place within that circuit stops it everywhere in that circuit.

But it's better to block the hose coming from the intake - the hot/supply/PRESSURE side. Blocking the cold side puts the heater core under slightly more pressure, which makes it more prone to leak or rupture.

The best way to do it is to use a 4-port valve, so coolant still flows.

ArdWrknTrk

Re: Help with wiring

Administrator

The famous Ranger 4port valve mod?

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

Gary Lewis

Re: Help with wiring

Administrator

In reply to this post by Steve83

Yeah, I thought about explaining all that. But when I didn't know if it was really the heater hose he was talking about I took the easy way out.

And, the Ranger 4-port is a good mod. I just have a cable-operated valve with no cable in Big Blue's supply-side heater hose and I turn it on in the winter and off in the spring. But I really want to try my vacuum-operated mod, so......

Gary, AKA "Gary fellow": Profile

1986F150Six

Re: Help with wiring

Administrator

Gary Lewis wrote

And, the Ranger 4-port is a good mod. I just have a cable-operated valve with no cable in Big Blue's supply-side heater hose and I turn it on in the winter and off in the spring. But I really want to try my vacuum-operated mod, so......

If you "T" off the vacuum hose going to the servo-motor for operating the fresh air vent door [passenger side, under hood], the heater still works but the hot coolant is cut off when MAX COOL is selected.

Gary Lewis

Re: Help with wiring

Administrator

Very true. But, you still have heat in the Vent position. And there are many times I'd like to have outside air temp coming through via Vent.

Gary, AKA "Gary fellow": Profile

Dk46

Re: Help with wiring

In reply to this post by Steve83

I already have the single port valve but can get the 4 port. Would the coolant not flow through the engine with the 2 port?

Danny K
1982 Bronco
351W
Holley 600
Deleted EEC3

Gary Lewis

Re: Help with wiring

Administrator

I think all of the engines but the 4.9L/300 six have a bypass where coolant will flow w/o the heater. Certainly the Windsors do. So there's no problem blocking off the heater, meaning the valve you have (2-port?) will work.

Gary, AKA "Gary fellow": Profile

ArdWrknTrk

Re: Help with wiring

Administrator

But in my 460 the bypass only goes from intake to water pump.

Whereas the heater loop picks up at the head side of the thermostat housing.

I don't really know about the I-6

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

1986F150Six

Re: Help with wiring

Administrator

I know of one 4.9L engine which has fine temperature control with one heater hose blocked during the warm months.

Steve83

Re: Help with wiring

Banned User

In reply to this post by Dk46

Dk46 wrote

Would the coolant not flow through the engine with the 2 port?

The engine isn't the issue; it's the heater core (and any sensors in the heater core loop, like EFIs have).

ArdWrknTrk

Re: Help with wiring

Administrator

In reply to this post by 1986F150Six

In my onboard bag of tricks I carry a 1/2" copper freeze coupling, to bypass the heater core if it pops like it used to with a cracked head.

You can always take the heater out of the loop.

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.