A500 42RH

[coronet69swede]

Hi you all.
In the process on renovate an 42RH from a dakota 3,9 to put in my car. I have read a lot of threads about the car work needed to be done and finally started.
On the gearbox on the left side close to the split right over the colerfitting. Whats it for. Messure pressure.
Second i have a picture i saved of the right side with some fittings and seem to remember something about OD and Lockup.
Any input on how when and what.
Third. Can i use anything from a 904 Lockup in the 42RH. maybee the forward clutch and shell because it contains 5 instead of 4 clutch disc. I have 275 to 300hp.
Fourth. I reed somewhere abot drilling a hole bigger in the OD
have a good one.
Johan

 

[TrailBeast]

Hi you all.
In the process on renovate an 42RH from a dakota 3,9 to put in my car. I have read a lot of threads about the car work needed to be done and finally started.
On the gearbox on the left side close to the split right over the colerfitting. Whats it for. Messure pressure.
Second i have a picture i saved of the right side with some fittings and seem to remember something about OD and Lockup.
Any input on how when and what.
Johan

View attachment 1716045594

View attachment 1716045596

As far as I know from your description the thing right above the cooling fitting is the front band adjustment.

On the OD and lockup connector, the center wire is keyed ignition 12v.
If I remember the front wire is grounded to engage OD, and the rear wire is grounded to engage lockup.
(I may have that backwards) but that is easy to google.

Mine is set up using pressure switches to shift into OD and lockup completely automatically.
The switches are adjustable for desired speed of engagement.
For example, with the 4th switch on and 5th off, the trans shifts 1-2-3-OD.
With both switches off it shifts 1-2-3 like a 904.

The way things are adjusted currently, OD comes on at 50mph and lockup at 70 with both switches in the auto position.

The switches on the shifter activate a relay to ground the front and/or rear wires of the 3 wire connector.

 

[coronet69swede]

Trailbeast. Thanks. I read your input somewhere. Is the picture i posted Your set up?
so when the speed goes up the pressure rise. What are the switches?
On the top picture. above the fitting behinde the 3 wire plug the is a 1/8 NPT plug.
That what i mean. it is a channel leading in to reverse drum rear sprag area.

 

[TrailBeast]

Trailbeast. Thanks. I read your input somewhere. Is the picture i posted Your set up?
so when the speed goes up the pressure rise. What are the switches?
On the top picture. above the fitting behinde the 3 wire plug the is a 1/8 NPT plug.
That what i mean. it is a channel leading in to reverse drum rear sprag area.

Not sure on that plug without looking it up, but there are diagrams online for all those.

The pic of the plumbing on the passenger side is not mine.
I didn’t want anything down there to get knocked off, so I ran a section of cooler line up to the back of the intake and mounted the pressure switches under the hood.
Out of harm’s way and way easier to get to for adjustment.

Where the plumbing is connected is the governor test port.
Pressure rises at that port with increased road speed.
When pressure rises enough it triggers the switch.
The switches are actually nitrous system fuel pressure switches.
When used as designed and advertised they actually work backwards to cut off the nitrous is there isn’t sufficient fuel pressure.
In our use they are normally off until the trans pressure rises enough to close the switch.
They came from NOS Express.
They have an allen screw under the rubber cap for adjustment.

 

[coronet69swede]

Superthanks.

 

[coronet69swede]

What is this for. By the arrow a smal hole no checkball.
By the star a 1/8 npt plug out.
Been looking in my books but cant find.

 

[rbkt65]

your pic #2 looks like part of a kit from PATC. they sell a kit to make the od/lu shift normally with certain pressure switches. look at their web site for more info.

 

[coronet69swede]

your pic #2 looks like part of a kit from PATC. they sell a kit to make the od/lu shift normally with certain pressure switches. look at their web site for more info.

Thanks. Will look in to it.