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big gear box problem

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My gear box came back form being repaired Thursday from Oregon. I put it in Sunday. I am having issures with the OD. The solenoid works but I am having trouble getting the lever to move up far enough to engage the OD. If I push the lever on the right side hard it engages but pops out. The guy who rebuilt it suggested it might be the operating valve and to carefully open remove insides with a magnet and clean everything well. It worked flawlessly before the gear box was rebuilt. The Od was never touched except to aline with the gear box when done. Any thing else I should check?
I'm also having trouble, now, with slipping in reverse. The cluthc and all are fine.
This has been the most frustrating experience since owning the car. I was so looking forward to just dropping the box in and go.
HELP!!!!
 

Keoke

Great Pumpkin
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Well TH, them be some strange happenings. However, lets see if first we can get the OD to engage. On the left hand side of the OD where the Solenoid is mounted is a side cover plate.Very carefully remove the cover exposing the end of the solenoid and a bolt on lever mounted on a shaft. Put the drill in the right hand lever and insert it into the OD case's hole. Now look at the lever bolted on to the shaft on the other side and see if the solenoid is raised up to the top of its stroke ."Note there is no power on the unit at this time".If it is not, remove the drill and power the unit up, put the gear lever in Third gear see if the solenoid goes up far enough to align the Right hand lever with the casting hole. If it does not move that far. Shut the power down and adjust the bolted on lever just a smallamount it the direction that raises the Right hand lever,And repeat the previous process. Small incremental adjustments of the bolted lever may be required to get the solenoid properly adjusted so the operating valve will function correctly.Let us see how you get on.--Keoke?
 

Dave Russell

Yoda - R.I.P
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Hi TH,
At the risk of being redundant I'll add a bit,
"It won't stay in OD without help & it slips in reverse."

The two may be related.

In hindsight, Bill should have tested the OD operation while he had the transmission

The cone clutch is the heart of the OD. It has a front AND a rear gripping surface. In direct drive & reverse, the clutch is forced to the front engagement surface by a group of springs. In OD the clutch is forced to it's rear position by hydraulic pressure.

https://www.britishcarforum.com/lore/article.php?id=073
Start here Item #7 - OD solenoid. Remove the rubber cover & check, clean the small contact.
If this contact is not making, the main solenoid operating coil will not operate & it will not have enough power to operate the OD valve. The contact should open when the solenoid plunger is in the fully engaged position. The solenoid input wire should measure less than one ohm to ground with the contact closed & around eight ohms with the contact open.

Go to item 5 & check the solenoid arm/operating valve adjustment by measuring actual ball lift while pushing the solenoid plunger fully up. It shold rise between .030" & .050 inch. A dial caliper may work well enough. The original factory, solenoid arm adjustment method of aligning the right hand arm with a hole & inserting a pin, often is not correct after years of wear & tear. Also see below:
----------------
The operate valve - solenoid adjustment. How it works. See the attached pic.
Note that the operating valve ball "D" has to seal to the top of the small seat on the top of the spindle "G" when the OD is operated, (spindle "J" raised by the solenoid & levers).

Also the ball must seal on the housing "F" when the solenoid is NOT operated, to remove line pressure which enters the valve through port "E" & flows to the OD operating pistons through port "L".

The valve spindle "J" has a small bleed hole "H" which lets operate pressure in the OD operate pistons bleed off when the OD is not operated.
---------------
All of this to say - Tap the 5/16" ball into it's lower seat to improve the seal "F", lap the top of the spindle to the ball at seal "G". Replace with a new 5/16" ball, available at hardware stores & bearing supply stores.

Why?
If the solenoid is not lifting the spindle far enough, the OD will be slow to operate.
If the spindle is lifting too far, it may not seat at "F" when the solenoid is released, see below.

If seal "G" is leaking, the OD will not have full pressure.

If seal "F" is leaking, or the relief hole "H" is plugged, tiny hole, the OD will be held partially operated & reverse gear will not hold. Partial clutch movement, or failure to completely release will leave the OD clutch in a more or less neutral position & reverse may not hold. Forward direct drive is also supplemented by another one way mechanical clutch so it may not slip in forward even if the OD front clutch is not making full engagement.

If the solenoid arm adjustment is such that the ball valve tops out against it's spring before the top solenoid contact opens, the solenoid will likely burn out, unless it is separately fused.

Hopefully, the problem will be that the top solenoid contact is not making & allowing the high power solenoid winding to operate.

Really sorry you are having a problem. Don't hesitate to send me an email if things aren't going well.
D
 

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tahoe healey
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Bill also suggested checking the valve. When I removed the bolt/upper ball seat, I found a few metal flakes of significant size. I cleaned everything and I hope this will solve the problem. I now need to adjust the arm onto the selenoid as per Nock's book and Keoke and Dave's advise. Thanks for the help. I'm hoping Dave is correct about the reverse thing.
I really appreciate you guys!
 

Dave Russell

Yoda - R.I.P
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Make sure that the inside of the spindle & the tiny hole down on the side of spindle shank are not plugged.

It might require reforming the upper splndle seat & the lower ball seat to get it really right. A worn or scratched ball can also create a valve leak. It's not that hard to fix.

Stretching the spring about 1/8" or so, may help the seating, the springs usually collapse a bit with age.
You can see most of the parts here: https://www.mossmotors.com/Shop/ViewProducts.aspx?PlateIndexID=28884
Attached is a pic on the control valve ball lift gage that I made to set the operating arm.
D
 

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tahoe healey
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Well, that was the problem! Set the over drive by the book and went on a test drive and it was sweet!I got reverse and everything. You guys were right on. Its amazing how one thing leads to another. I'm sure the metal flakes were from the deteriating first movement shaft.
My goal was to have it done before the first snow. It snowed on the test run. The new rear engine seal didn't do much but I'll look into it in the spring.
Thanks again
 

Keoke

Great Pumpkin
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Well TH, Glad you be gettin going as I thought the adjustment may have gotten jiggled in transit.--Keoke- /ubbthreads/images/graemlins/thumbsup.gif


OH I saw Don over the weekend and had agood chat with him.
 
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