clutch interlock switch bypass?
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From: Angier, NC
Before clutch interlock switches I had several manual vehicles and I'd often if not always start them with the transmission in neutral. When I got my 86 I quickly discovered that the clutch needed to be fully depressed. If you don't know where neutral is then it could be a problem. I'm recently having an intermittent starter circuit failure. If I pump the clutch a couple times and hold the clutch down it starts. So cycling the pedal helps it connect. I'm going to be looking at it soon. I looked for replacement switches and haven't found one yet. Anybody know who sells them? Might not need one yet as it could be an adjustment or some contact cleaner. I do have tilt but if it's the broken piece you never can start till repaired. I'm leaning towards my issue being the CIS.
I was taught from an early age to ALWAYS push the clutch in when starting. This way even if not in neutral it will not be a problem.
When did they start putting the clutch switch in our trucks as both of my 81's did not have them.
Dave ----
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Keep in mind the ignition switch is actually 4 separate poles (switches) in a common housing. Even if one pole works fine, it does not mean they all do. The pole which controls the ignition may be fine. The only fault may be with the pole controlling the starter circuit.
Are you sure this vehicle even has a clutch interlock switch and associated wiring? Please see the following thread:
https://www.ford-trucks.com/forums/1...h-mystery.html
It would appear the clutch interlock switch was introduced sometime during the 1984 production run. My '84 must have been close to the changeover point. It has the switch but no wiring.
https://www.ford-trucks.com/forums/1...h-mystery.html
It would appear the clutch interlock switch was introduced sometime during the 1984 production run. My '84 must have been close to the changeover point. It has the switch but no wiring.
Last edited by My4Fordtrucks; Mar 15, 2026 at 12:53 PM.
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I'm thinking the reason clutch interlock switches are not on rockauto is that people just jumper the two wires together. After my recent truck stalling out on a railroad track I'm liking the idea of being able to walk off a situation like that as this particular crossing had a slight valley towards the tracks. I got out and started rocking the truck back and forth and finally got it off the tracks but it wasn't easy. Without the clutch interlock I could have walked the truck off with the starter motor.
I agree that if you don't know where neutral is then by all means push in the clutch to be safe. But given the poor replacement parts for juice clutches and a limited number of clutch strokes per master and slave you can extend the life of your clutch system by not using it every start. YMMV.
I agree that if you don't know where neutral is then by all means push in the clutch to be safe. But given the poor replacement parts for juice clutches and a limited number of clutch strokes per master and slave you can extend the life of your clutch system by not using it every start. YMMV.
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From: Virginia
I'm thinking the reason clutch interlock switches are not on rockauto is that people just jumper the two wires together. After my recent truck stalling out on a railroad track I'm liking the idea of being able to walk off a situation like that as this particular crossing had a slight valley towards the tracks. I got out and started rocking the truck back and forth and finally got it off the tracks but it wasn't easy. Without the clutch interlock I could have walked the truck off with the starter motor.
I agree that if you don't know where neutral is then by all means push in the clutch to be safe. But given the poor replacement parts for juice clutches and a limited number of clutch strokes per master and slave you can extend the life of your clutch system by not using it every start. YMMV.
I agree that if you don't know where neutral is then by all means push in the clutch to be safe. But given the poor replacement parts for juice clutches and a limited number of clutch strokes per master and slave you can extend the life of your clutch system by not using it every start. YMMV.
But I always press in on the clutch during starting, from habit and during a very cold morning turning the transmission with the engine puts more load on the starter. But I do like the option of starting while in gear, I have saved myself once also with that.
Last edited by Franklin2; Mar 15, 2026 at 02:27 PM.
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From: Angier, NC
I had a motor that I am sure was always hooked to a auto that had a shi* load of end play.
The cast crank had a grove cut into it it was that bad. All bearings showed copper, did not check cam bearings
I replaced all the bearing but cam bearings, put a big cam in it, killer intake manifold and went drag racing spinning it to 6+k
It ran great even with the end play and it can also happen with a motor hooked to a auto.
Dave ---
The cast crank had a grove cut into it it was that bad. All bearings showed copper, did not check cam bearings
I replaced all the bearing but cam bearings, put a big cam in it, killer intake manifold and went drag racing spinning it to 6+k
It ran great even with the end play and it can also happen with a motor hooked to a auto.
Dave ---
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I have read the torque converter can “balloon” and cause that to happen to the crankshaft.
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From: Angier, NC
The motor and trans came out of a Jeep Wagoner and IIRC the motor stopped running because the pin for the distributor gear broke.
I am guessing the motor had low oil PSI because of the bearings and was parked.
I put the work out I was looking for a TH400 from a Jeep and the guy said he had one even let me use his tow truck to go get it.
I kept the motor, transmission and a few other odds and ends that would fit my car and scrapped the rest.
I believe when the converter "balloons" the trans also stops working because the fins in the converter and not close enough to spin the fluid.
My 4000 stall race converter had a plate welded to keep it from ballooning and I would have been pissed if it did at $1000!
As they say you pay for speed
Dave ---
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I'm dash diving today, looking up at my clutch interlock switch. It appears that since I have cruise control the two switches are married...joined at the hip at first look. And perhaps sharing a plug in? I'm going back under to look deeper but if anyone has some advice let er rip...
The interlock switch has a trombone like slide that pulls out and I guess when fully out to the low E (for trombone players only) it's supposed to engage the interlock switch juice. I'm going to check for wear on the slide hole, maybe add some material to increase the throw? Perhaps there is an adjustment? I don't want to screw up the cruise while at it...
The interlock switch has a trombone like slide that pulls out and I guess when fully out to the low E (for trombone players only) it's supposed to engage the interlock switch juice. I'm going to check for wear on the slide hole, maybe add some material to increase the throw? Perhaps there is an adjustment? I don't want to screw up the cruise while at it...
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From: Angier, NC
What are the wire colors?
If you look at the starter solenoid where the wire connects to the "S" lug what is that color?
I want to say the color is red with blue stripe but whatever that color wire is I would think you will find the same color wires at the switch.
Dave ----
If you look at the starter solenoid where the wire connects to the "S" lug what is that color?
I want to say the color is red with blue stripe but whatever that color wire is I would think you will find the same color wires at the switch.
Dave ----
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What are the wire colors?
If you look at the starter solenoid where the wire connects to the "S" lug what is that color?
I want to say the color is red with blue stripe but whatever that color wire is I would think you will find the same color wires at the switch.
Dave ----
If you look at the starter solenoid where the wire connects to the "S" lug what is that color?
I want to say the color is red with blue stripe but whatever that color wire is I would think you will find the same color wires at the switch.
Dave ----
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Update...It appears that a shot of contact cleaner on top of the switch plunger and some exercising of the plunger has solved my problem for now. You can push in the button and cycle the switch without depressing the clutch. So before you go cutting wires try some contact cleaner.
FTE Legend
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From: Angier, NC
Good to hear the cleaner worked but I would never cut wires just because the switch did not work.
As I said look at the solenoid S lug wire color and the same color wire should be on that switch, just jump the 2 wires together and you no longer need to push the clutch in to start but do so anyway.
Dave ----
As I said look at the solenoid S lug wire color and the same color wire should be on that switch, just jump the 2 wires together and you no longer need to push the clutch in to start but do so anyway.
Dave ----
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Yep, maybe you can jumper them. I would like to have that emergency crawl out of harms way without the interlock switch. Since I also have cruise and first look they might be on the same switch and plug in complicating the ability to un plug and jumper in the plug. I just wanted to get it operational because I need to do some driving this week. I'm go to have to clean off the front seat so I can stand on my head in the other direction to see what's going on. It's crowded up in that area...
I do push in the clutch to start because of the interlock. Then I take it out of gear to neutral to warm up the engine. I don't hold the clutch pedal then. Do you sit in your truck holding the clutch in while warming the motor? Nah you put it in neutral!
I do push in the clutch to start because of the interlock. Then I take it out of gear to neutral to warm up the engine. I don't hold the clutch pedal then. Do you sit in your truck holding the clutch in while warming the motor? Nah you put it in neutral!
FTE Legend
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From: Angier, NC
I dont let mine warm up that long but yes in neutral and in over drive to spin the trans faster to make it shift easier.
Start it up, back out of garage, neutral with over drive, put seat belt on, check gauges, back in direct and in 2nd (granny first) and start diving.
Might run a little lean till it gets some heat in her but otherwise no problems even on the coldest days I might use the truck.
Dave -----
Start it up, back out of garage, neutral with over drive, put seat belt on, check gauges, back in direct and in 2nd (granny first) and start diving.
Might run a little lean till it gets some heat in her but otherwise no problems even on the coldest days I might use the truck.
Dave -----
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Mountain Pass
Joined: Sep 2013
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From: Santa Rosa, Ca
ok update. been super busy and havent touched the bronco because i HAVE to finish my jeep commando first (get it driving to move around) before i even start on the bronco but its been annoying trying to start it from the solenoid.
it ended up being the clutch switch. really wanted to figure it out before ordering a new ignition switch. i was able to pop it off and a mini fuse pressed right into place like it was meant to be. in fact i may just heat strink it on and leave it be. whats cool is the cruise control has its own separate clutch switch. when it comes time we'll see if that works.
the thing is a little tough to get off. the clip holding it on is up top where you cant see it. you have to feel for it and i got a pick tool under it pretty quickly.
it ended up being the clutch switch. really wanted to figure it out before ordering a new ignition switch. i was able to pop it off and a mini fuse pressed right into place like it was meant to be. in fact i may just heat strink it on and leave it be. whats cool is the cruise control has its own separate clutch switch. when it comes time we'll see if that works.
the thing is a little tough to get off. the clip holding it on is up top where you cant see it. you have to feel for it and i got a pick tool under it pretty quickly.
