Another 700R4 Converter wiring? Please, help...

[Flu-by-U]

I was about to use Tx Firefighter's wiring diagram for the R4 lock up in my trans today. (Sorry, I can't find a copy of his diagram right now.)

I dropped the pan and found a two pronged switch that is in his diagram AND a one prong switch under the pan.

In all the research I have done for this mod and pictures I have seen I have never seen BOTH of those in the same valve body. (I'm confused)

I have a blue wire outside the trans on the 4 pin, that runs to the red wire inside the trans,
that runs to the solenoid in the front of the pan,
and the black wire from the solenoid runs to the single pin switch in the rear, that you can see in the picture.




This motor & trans came out of an 87 GMC 3/4 Ton van. (Not sure if that matters or not.)

I don't know if all this wiring that is currently in the trans is scrapped & not used?

In his diagram, (if you know the one I am speaking of, sorry.) the wire coming off the two prong switch to the solenoid...
Does it connect to the red or black wire of the solenoid or the red one?

What size fuse should I use for this?

What are the pros & cons of not using the brake switch?

Sorry for all the ??? but, I just want to make sure I do this right before I replace the pan & fill her up w/ fluid. (getting anxious.)

This is the last thing I have to do before firing her up for the first time.

Any guidance you can give will be much appreciated...

[Flu-by-U]

Nobody?

Nothing?

As Phil Collin's would say, "No reply at all."

[Flu-by-U]

OK...

Here is the wiring diagram I am referring to...

It is the one on the left, the normal kit diagram...

http://700r4.com/tech/tcc/brake_install/diagram.shtml

Any help is much appreciated...

[VetteVet]

Don't know if this will help.

http://www.73-87.com/7387garage/drivetrain/lockup.htm

[clinebarger]

There are several different ways to do the same thing..............This is "MY" way of doing it with what you have.

Just to familiarize you with what pressure ports do what, I labeled them

White arrow= 4th gear oil
Orange arrow= 3-4 downshift oil
Blue arrow= 3rd gear oil

Normally Open= (N.O.) Normally Closed= (N.C.)

Your 4th clutch oil switch is N.O., Hook the Black wire of the lock-up solenoid to the 4TH clutch switch. Hook the Red wire of the lock-up solenoid to "pass through connector" . Connect the wire coming from the trans to the "lock-up" side of a "Dual Brake switch", The other terminal of the lock-up side will hook to a ignition hot. A "dual brake switch" will have a N.O.-brake light curcuit & a N.C.- lock-up curcuit. The purpose of killing power to the lock-up solenoid during braking....If you lock-up the rear wheels with the converter engaged..The engine will stall.

The single prong N.O. 4th clutch switch you have now will close when in 4th gear providing a ground to the lock-up solenoid, The ground path is provided through the switch body/valve body.

A 15 amp fuse will work.

[clinebarger]

That harness looks weird, Ive never seen those white splice things before, I would repair or replace it.

[fleetsidelarry]

Clinebarger, the method you describe will lock the converter immediately upon shifting into 4th, is that right? only unlocks if you brake or the transmission downshifts? if so, won't either a toggle switch (like many of us have) or a vacuum switch be needed to unlock in 4th?

[clinebarger]

Originally Posted by fleetsidelarry

Clinebarger, the method you describe will lock the converter immediately upon shifting into 4th, is that right? only unlocks if you brake or the transmission downshifts? if so, won't either a toggle switch (like many of us have) or a vacuum switch be needed to unlock in 4th?

This will close the lock-up solenoid in 4th gear,
Most 700R4s made before 89 have a Converter Clutch Throttle Valve in the valve body, That will un-lock the converter under heavy acceleration.

If it has the Converter Clutch Throttle Valve bore eliminated or has a plug, Running a vacuum switch is a good idea. I really dont like the toggle switch idea.....

[cableguy0]

Cant help with the lockup wiring but get rid of the junk connectors on the wires. Solder the wires together or replace them altogether. Your just asking for connection problems with those splice connectors.