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OD doesn't disengage

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John_Progess

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After restoration OD didn't work. AS per suggestions I removed console, tranny tunnel and pushed the lever on right side of tranny down and the OD engaged. I did not get the pinch bolt tight enough so the solonoid lever did not move the operating valve. I adjusted as per the book and the OD worked fine. I was able to engage and disengage. The lever on the right side of tranny was a little off so I adjusted it so it is aligned with the hole. Then I noticed that it engaged but didn't disengage the next time out. Today I started out with the OD switch off and when I shifted into third I felt the OD shift after about 4 seconds or so. Stopped the car, turned the switch on, the solonoid engaged, shut off switch, started out and the OD was still engaged when I shifted into third. Any suggestions would be apreciated. Have a good day!

John
 
John:

Put the adjustment back where you had it. No doubt the "correct" adjustment you just made leaves the OD valve slightly open when the solenoid is not activated.

My car is the same way, if I adjust it with that alignment hole as per the shop manual, it does not work properly.

You just need to set it so the valve is definitely open when the solenoid is engaged and definitely closed when it is not. I suspect you are very close to having it right.

To add to the drama there has to be enough stroke so the solenoid when activated opens those tiny internal electrical contacts to switch it from pull-in to the holding coil. Otherwise, you will draw too much current and possibly fry the OD wiring harness. I usually put an ohmmeter on the solenoid and work the OD linkage by hand to make sure the coil resistance increases when the linkage is moved manually to the activate position.

Bill.
 
John, I'm glad you tracked it down to the solenoid lever adjustment. Bill (above) has the right answer .. you adjusted it too far. Did you put the tunnel cover back on already?
 
I readjusted the control rod and it will engage and disengage but it is not consistant. Bill, you said you did not adjust as per manual. Does that mean your lever is past the hole or before the hole. I have not installed the tunnel so I am still trying to get it right. Do you have to depress the accelerator when you turn the dash switch on to get the OD to engage and likewise bump the throttle to disengage it? Thanks for the help and have a good day!

John
 
I know that if the throttle switch is adjusted correctly, you have to bump the throttle (depress the accelerator) to disengage OD. I've always had the accelerator down somewhat when engaging the OD -- never had to do anything else.
Is both engaging and disengaging inconsistent, or do you mean dependent on the throttle movement. If the latter, that is appropriate.
 
Sounds odd but if you recently changed the oil and overfilled it I had a similiar issue.


Michael.
 
John:

I don't remember if my lever is set short or past the hole (I think it is short), I just know it is not on the hole. Can't tell now without removing that bloddy tunnel!

The throttle must be cracked opened a bit to disengage the OD if the throttle switch is set properly. This switch has no effect on engaging the OD. If the throttle switch is broken or badly adjusted so it does not close when you open the throttle, the OD will will not disengage. You can eliminate the throttle switch for testing purposes by shorting the two leads together at the switch. In this mode, the OD should disengage whenever you turn off the dash switch regardless of the throttle position.
 
John_Progess said:
After restoration OD didn't work. AS per suggestions I removed console, tranny tunnel and pushed the lever on right side of tranny down and the OD engaged. I did not get the pinch bolt tight enough so the solonoid lever did not move the operating valve. I adjusted as per the book and the OD worked fine. I was able to engage and disengage. The lever on the right side of tranny was a little off so I adjusted it so it is aligned with the hole. Then I noticed that it engaged but didn't disengage the next time out. Today I started out with the OD switch off and when I shifted into third I felt the OD shift after about 4 seconds or so. Stopped the car, turned the switch on, the solonoid engaged, shut off switch, started out and the OD was still engaged when I shifted into third. Any suggestions would be apreciated. Have a good day!

John
Click to expand...
:savewave:
Put all adjustments back just like you had them .Lever and hole rarely exactky line up , just a good starting point when aligning OK----Keoke- :yesnod:
 
Keoke,
I realigned everything including reset the throttle switch and I have not been able to get the OD to engage at all. The solonoid works, the lever is aligned with the hole and nothing. Does this mean I have a pressure problem? Is there any other diagnostics I should do? Thanks for all the help and have a good day!

John
 
You didn't mention checking the operating valve lift after adjusting the clamped on arm on the solenoid side. Maybe you
did but didn't mention it.
Here is the relevant portion from a document that Dave had sent me when I was having o/drive problems. I can email you all of my O/drive info that I have, just PM me.

Ed

5- Operate valve adjustment
a- Set control valve ball lift to .030" to .040". Measure with dial indicator. Cap & spring removed.
Adjust clamped operating arm. Verify movement with the solenoid plunger, not the arm.
 
I'm confused, John. You said the OD engaged, but then didn't disengage. Now you say it doesn't engage at all. If it engaged at one time and you changed the adjustment, it can't be a pressure problem. It comes back to the solenoid lever adjustment. Even though the OD switch is turned off, if you don't depress the throttle (when the throttle switch is adjusted correctly), the OD will still engage when you shift into 3rd until you depress the throttle sufficiently.
 
To simplify trouble shooting, take the (damned) throttle switch out of the circuit (put both wires under the same terminal, for the time being).

At this point, only the on/off switch and the 3rd/4th gear selector switch are controlling power to the solenoid.

Try this: switch on the ovd, and if it doesn't energize the solenoid, pull around on the shift lever (while in 3rd or 4th). I've seen the gear selector switch so worn, that you could "downshift" out of ovd (for passing) by just pulling the shift lever towards you (lefthand drive). When you'd release the tension on the lever, it would spring back and the ovd solenoid would energize again.
 
Ed K,
I would really appreciate your info on trouble shooting the OD. My email is johnprogess@comcast.net (not progress..a common mistake). I did look at the valve lift and it did move. I will measure it today.

Tim,
I have been messing with this thing for a week. I finally got it to engage and disengage several times, then once it did not disengage. I finally got it to work a few more times but now it won't engage after I have reset everything.

Randy,
The solonoid has worked fine through all this. It lifts as it should and rotates the lever arm. The lever arm does not move much, about 1/2 the diameter of the lever arm hole (3/32" or so). I set the throttle switch as per the book and it appears to work fine but I will take it out of the loop and try again today. There is an adjustment under the solonoid valve that seems limit the downward movement, not a rubber pad as in the book and no mention about this adjustment.
The car has just been completed from a 27 month total restoration. Oil level is full and I used 30 wt non detergent oil as per John at Quantum Mechanics. Thanks again for all the help and everyone have a good day!

John
 
Norman Nock in his Tech Tips on adjusting the solenoid lever says:
1. Loosen adjusting nut.
2. Using a 3/16" drill bit, insert it into the hole on the right side. (This holds the lever in its "on" position)
3. Activate solenoid. (by moving shift lever to right with key on and OD on)
4. Tighten adjusting nut (while solenoid is activated)
5. MAKE SURE THE ARM IS TOUCHING THE ACTUATING FLARE at the bottom of the solenoid plunger (the flat part that lifts the lever. "If this part of the adjustment procedure is not done properly, you are wasting your time because the overdrive will not work!"

Also, Norman says: "the last 1/4" of the solenoid movement is what releases the hydraulic pressure to activate the OD." You should have more travel of the solenoid than 3/32"

Are you still able to actuate the OD manually by pressing down on the right side lever while running in 3rd or 4th gear?
If so, then it continues to be an actuating arm or solenoid travel issue.

Best wishes....
 
Tim,
If I move the lever on the right side of the tranny by hand I get about .060" movement of the control valve up and down. If I use the solonoid it is only about .010" of up and down movement. I looked at the solonoid lever arm and the vertical clearance between the hook in the lever arm and the sholders on the solonoid is .080" which means that the solonoid moves that much before engaging the lever arm which turns the control rod and hence very small up and down movement of the control valve. I think I will try to shim this and see what happens. I looked at the solonoid and it has about 3/16" total travel. I may have to lower the bottom stop to give more overall solonoid travel. I did not get a chance to drive the car today. The 3/32" of movement I was refering to is the movement of the lever arm on the right side of the tranny with the 3/16" dia. hole. I really appreciate all the help. Thanks and have a good day!

John
 
Just thought I'd add, if o/d does not disengage, under no circumstances use reverse gear, you almost certainly will damage the unidirectional bearings in the o/d unit. cheers Genos2
 
Is there anyway you could take a picture of the solenoid and arm at rest? The bottom of the solenoid plunger should be touching the lever arm at rest. There should be no "free-play" between the solenoid plunger platform (the ledge that lifts the lever arm) and the lever arm. You need to be careful about shimming the plunger, it may prevent it from going up far enough to depress the little button at the top of the solenoid that switches the power from high-lifting (20 amps) to low-maintaining power (2 amps). It shouldn't need shims if you do the adjustment correctly.
 
ODSolenoidleverarmadjustment.jpg


Remember, you must have the solenoid energized to tighten the adjusting nut, making sure the lever arm (ITEM C) is in contact with the platform of the solenoid plunger (POINT D in the drawing)

<span style="font-style: italic">This drawing is from Norman Nock.</span>
 
Hi John,

I just emailed you all of the o/drive doc I had.

If you only have .010 ball lift you need to fix / adjust

to obtain the required .030 - .040 inch valve/ball lift.

Once you get the required lift your o/drive should engage again.

Good luck !

Ed

:hammer:
 
Tim,
There is no clearance between the lever arm and the bottom of the solonoid plunger. The clearance is at the top of the lever arm. My solonoid plunger is moving about 3/16" and I am wondering if it is enough. I will check again today and see if I can get enough movement.
Ed,
I got your email. I can get plenty of movement in the control valve by moveing the lever arm on the right side of the tranny but not with the solonoid. I will play with it again and use a battery charger to move the solonoid and see what happens. Thanks alot and have a good day!

John
 
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