Help, truck stranded...wont start (firewall issue)

[Optikalillushun]

Had to use my 88 today, parked it about 10 miles from home...went to get back in to start it and nothing. it has the firewall seperatating from itself.

where is the clutch interlock switch and how can i bypass it.

 

[towcat]

Had to use my 88 today, parked it about 10 miles from home...went to get back in to start it and nothing. it has the firewall seperatating from itself.

where is the clutch interlock switch and how can i bypass it.

the clutch interlock is on the master cylinder pushrod itself.
the cruise control is there too, so you'll see four wires.
if you're stranded, you can always jump the solenoid on the fender, just make sure you're not in gear.
i just looked in my alldata, the wire you want to jumper is the red with light blue stripe.

 

[MIDNIGHT RIDER]

First mod I do on all my trucks.

Look at clutch-rod under the dash and find the clutch-switch; don't get this confused with the brake-light switch.

Un-plug the wires from the switch, skin off insulation from both wires, twist them together and tape.


If you wish, you can get fancy and splice in wires to a hidden mystery switch, such that when this switch is OFF, the truck cannot be started normally.

Have fun.

 

[Optikalillushun]

the clutch interlock is on the master cylinder pushrod itself.
the cruise control is there too, so you'll see four wires.
if you're stranded, you can always jump the solenoid on the fender, just make sure you're not in gear.
i just looked in my alldata, the wire you want to jumper is the red with light blue stripe.

thanx, i wasnt sure where abouts it was as it was dark when i was lookin. i tried to jump the solenoid but it didnt work.

 

[smoking89IDI]

thanx, i wasnt sure where abouts it was as it was dark when i was lookin. i tried to jump the solenoid but it didnt work.

you have to put battery power to the small post on the solenoid, then it will crnak no matter what is in the way of the truck so keep it out of gear

 

[h2odrx]

you didn't park on a hill?

 

[LCAM-01XA]

If you wish, you can get fancy and splice in wires to a hidden mystery switch, such that when this switch is OFF, the truck cannot be started normally.

Ha, that's just what I did with my old C10 Chevy, it was a three-on-the-tree truck when it left the factory but someone swapped in a TH350 slushbox so the clutch safety switch was no longer needed - kill switch it became, nicely hidden under the dash. Pedal got zip-tied down to the firewall, made for a nice clamp for the darn rubber mat on the floor.

 

[Optikalillushun]

instead of cutting the wires back n all right now, can i just use another piece of wire to jump the two wires by putting them in the pigtail end? i dont really have the time to do all that...its parked on a busy street and i dont wanna get run'd over

 

[towcat]

instead of cutting the wires back n all right now, can i just use another piece of wire to jump the two wires by putting them in the pigtail end? i dont really have the time to do all that...its parked on a busy street and i dont wanna get run'd over

you could do that, but if you can't light it off with shorting the fender mounted solenoid, you have bigger problems.

 

[MIDNIGHT RIDER]

thanx, i wasnt sure where abouts it was as it was dark when i was lookin. i tried to jump the solenoid but it didnt work.

Just how did you "jump" the solenoid ??


To "jump" or bypass the starter-relay(solenoid), take a U-shaped section of heavy-gauge wire and touch both ends to the large studs on each side of the relay(solenoid); there is no need to mess with the smaller wires.

Before attempting this, make sure the transmission is NOT IN GEAR.


All the starter relay/solenoid is is an electrically-controlled remote SWITCH that momentarily makes the circuit between the battery and starter.

I really don't know why it ever became known as the "solenoid", since it is in fact a RELAY and not a SOLENOID.

A solenoid moves a rod in and out to electrically control such things as the water-valves on the back of a washing-machine.

 

[gandalf]

Am I missing something here? I was taught the procedure by a Con-Ed man at the top of Kaiser Pass, where no self-respecting tow truck driver would have ventured.

The ignition has three basic positions, stop, run, start. You can jump the solenoid and crank the engine forever, but if the ignition isn't in the 'run' position, all you're going to do is run down your battery and wear out your starter. I'm surprised nobody above mentioned this.

So, the sequence is: pop the hood, make sure the truck is not in gear, turn the ignition to the 'run' position, and jump the solenoid.

I'm sure I'm preaching to the choir, but thought I'd mention it anyway.

 

[towcat]

Am I missing something here? I was taught the procedure by a Con-Ed man at the top of Kaiser Pass, where no self-respecting tow truck driver would have ventured.

The ignition has three basic positions, stop, run, start. You can jump the solenoid and crank the engine forever, but if the ignition isn't in the 'run' position, all you're going to do is run down your battery and wear out your starter. I'm surprised nobody above mentioned this.

So, the sequence is: pop the hood, make sure the truck is not in gear, turn the ignition to the 'run' position, and jump the solenoid.

I'm sure I'm preaching to the choir, but thought I'd mention it anyway.

you sure it wasn't gary who you ran into there?
(gary/icanfixall is a ex-employee from that place)

 

[LCAM-01XA]

I always do this:
1) pull small wire off starter relay on fender
2) put key to "run" (well, I flip switches, but ya'll got keys), that obviously wakes up the IP and the slushbox PCM
3) take a wrench/screwdriver/knife and shove it between the post for the small wire and the large post with gazillion wires connected to it (that's constant battery power)
4) watch the truck come alive

Jumping the two large posts of the starter relay is generally NOT a good idea as there can be quite the current flowing through there, whereas if you do like I do you're only powering the control circuit for the relay (which takes very little current) and you let the relay itself to take care of the big current (like it should). Now if the starter relay is shot then yeah, you ain't got no choice but jump the big terminals directly, but I'd avoid that unless entirely necessary.

 

[Optikalillushun]

ill try the "relay" again, beats the pants off crawling under the dash to jump the clutch interlock switch.

 

[Optikalillushun]

welp, figured to try to start it and BAM didnt have to do anything. the firewall must expand just enough when its the engine is hot to cause it to not enguage the switch all the way.