700r4 Wiring Help.

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custodian

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I've switched from the 6.2 diesel to a 350. Now working on my wiring and needing help with the 700r4 wiring.

I looked through the forum and didn't find what I was looking for.

This is what I have: 1 green wire that goes to the plug in the trans. 1 green wire that I "think" goes to a test connection. 1 blue wire goes inside and goes up to a wire harness, maybe to the back of the gauge cluster.

Now my question:

The plug in the first picture that was attached to the fuel injector on the diesel. The green wire on the right goes to the trans, the other green wire went to the second picture (plug). The blue wire went inside the cab to the wire harness. The 4th picture is where the plug attached to the fuel injector, the plug on the left.

What do I need to make the lockup work?

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bucket

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I don't think those wires have anything to do with the lockup?

From the factory, early carbed trucks had a vacuum switch that controlled the lockup and I believe it was only operational when the engine got up to a certain temp. Later TBI trucks, they had the lockup controlled by the ecm.

There are aftermarket lockup control kits that are fairly cheap and easy to install.
 

custodian

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I don't think those wires have anything to do with the lockup?

From the factory, early carbed trucks had a vacuum switch that controlled the lockup and I believe it was only operational when the engine got up to a certain temp. Later TBI trucks, they had the lockup controlled by the ecm.

There are aftermarket lockup control kits that are fairly cheap and easy to install.

This truck used to be a diesel. These wires do control the lockup. I took the roundish controller apart that was on the injector and found the switch that makes contact to supply voltage to the lockup solenoid.

Your right about the aftermarket lockup control. There is a kit that uses the pressure switch and the vacuum switch. I'll go by and talk to the guy that built my trans, which has zero miles on it, not yet put trans fluid in it yet. Don't want to void any warranty he put on it.

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bucket

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That diesel stuff is foreign to me. So that must be some kind of load sensor and/or throttle position sensor on the injection pump?
 

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That diesel stuff is foreign to me. So that must be some kind of load sensor and/or throttle position sensor on the injection pump?


Seems like that'd be speed related.
 

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I'm going by the trans shop tomorrow and speak with the guy that built the trans.
 

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I've been searching on and off all day today while working on my wiring for the 350. I've read and seen a couple of pictures to where there is a vacuum switch, mounted next to the brake booster that the wires hook to on a gas motor for the 700r4 lockup.

I guess I need to find someone to take a picture of what they have and maybe a part number.

My truck is an 85 C10 with the 700r4 only used between 85-87. 1 wire going to the connector.

REMEMBER, I'M SWITCHING FROM DIESEL TO GAS.
 

custodian

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I think this is what I need.

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Turbo4whl

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Yes, that is the vacuum Tip In switch.

Some diagrams I found. Not the correct one.

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bucket

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I've been searching on and off all day today while working on my wiring for the 350. I've read and seen a couple of pictures to where there is a vacuum switch, mounted next to the brake booster that the wires hook to on a gas motor for the 700r4 lockup.

I guess I need to find someone to take a picture of what they have and maybe a part number.

My truck is an 85 C10 with the 700r4 only used between 85-87. 1 wire going to the connector.

REMEMBER, I'M SWITCHING FROM DIESEL TO GAS.

That's why I suggested the aftermarket setup. It works very similar, but there's no need to track down original parts that may or may not work.
 

Ricko1966

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No need for a kit 1 fuse 1 relay , use the 4th gear switch in the valve body to close the relay and lock up the converter. If you just lock up the converter with the 4th gear switch you risk burning up the switch but a relay mounted somewhere accessible is so much easier to change. 4 wire relay, fuse #30 from a switched power source #87 to torque conv. lockup, other side of converter lockup to ground. 85 and 86 are relay control wires switch them with the 4th gear switch.
 

bucket

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No need for a kit 1 fuse 1 relay , use the 4th gear switch in the valve body to close the relay and lock up the converter. If you just lock up the converter with the 4th gear switch you risk burning up the switch but a relay mounted somewhere accessible is so much easier to change. 4 wire relay, fuse #30 from a switched power source #87 to torque conv. lockup, other side of converter lockup to ground. 85 and 86 are relay control wires switch them with the 4th gear switch.

But then the converter will not unlock in 4th when needed? That would drive me nuts.
 

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Wire it in thru a factory brake light switch with the normally closed contacts for the converter clutch. It would then unlock and lock automatically when you apply/release the brakes.

On one of the Olds forums I recall a guy offering control boxes he designed that had timers built in. Once the trans shifted into 4th, after so many seconds the converter locked. Hit the brakes, it unlocked. Release the brakes, after a few seconds it would lock again. He also used a vacuum switch as a input, also with a time delay. It seemed like a well thought out design, it would get rid of the abrupt on/off. I suppose someone with a background in electronics could build something similar.

Chrysler also had pressure switches designed to close at specific PSI, they used them to lock their converters before computers were in every car and truck. I would think you could put one in the governor oil circuit, then when governor pressure reached a certain point, the switch closes.
 
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