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TR2/3/3A A type Overdrive Seal

CJD

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Got the TR2 running, but that highlighted a couple issues.

I have a leak from the control shaft where it enters the solenoid plate. This is the shaft that goes crosswise through the overdrive, and the solenoid turns it to activate the OD. Since I rebuilt it 3 years ago, I have no memory of any seal for that shaft. In my pics, it doesn't appear there ever was a seal on the shaft.

Has anyone had a leaky shaft? If so, how did you seal it? All that comes to mind looking at it would be to install an exterior "o" ring between the plate and the actuating arm that clamps to the shaft?!?
 

HAWAIICJ

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Moss motors Overdrive parts diagram shows 866-030 as an Operating shaft O-ring seal. There is one on each end although the one on the right side (opposite of the accumulator cover) would be easy to replace once you removed the operating shaft setting lever and pin. GRID200114.jpg



I haven't done these before but plan on replacing these o-rings when I overhaul my OD and trans this fall/winter.
 
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titanic

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John-The o ring on the accumulator cover plate is actually on the inside of the plate. Easy to replace after the cover is removed. The o ring on the other side lives under the setting lever which is secured to the shaft by a pin. Removal of the pin may be difficult with the trans. in the car. The last time I had my OD apart, I machined a set screw to replace the pin, which makes removing the setting lever&o ring easier to replace.
The o rings are -109, which are a common size and available locally.
Berry
 
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CJD

CJD

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Thanks Dave, Berry. I missed that there was an o-ring! At least it's on the easy side. I appear to also be missing the item 57, collar, which I suppose holds the oring in place.
 
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CJD

CJD

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Sure enough...I found a copy of the manual, and I overlooked the collar and seal. It appears in the diagram that is goes on the outside, under the actuating arm??



 

CraigC

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Sure enough...I found a copy of the manual, and I overlooked the collar and seal. It appears in the diagram that is goes on the outside, under the actuating arm??

The o-ring fits in a recess on the INSIDE of the cover. The collar's job is to locate the arm correctly under the solenoid, and has nothing to do with the o-ring
 

titanic

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The o-ring fits in a recess on the INSIDE of the cover. The collar's job is to locate the arm correctly under the solenoid, and has nothing to do with the o-ring
Thanks Craig-I was afraid I was having a hoof-in-mouth or senior moment. The accumulator cover I have came from a TR6 and I was beginning to think that there may have been a change from the early A types. The manuals do appear to show the o ring on the outside.
Berry
 

sp53

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It runs through!!!!!!, but you knew it would. Whereas, I am always very happy when they start, you must have been also.
steve
 
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CJD

CJD

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Well, spent 3 hours under the running car today. It turns out the collar and seal are there. The early OD I have does not have an internal recess for the seal, so it looks like the diagrams above. It appears it was leaking because I did not slide the solenoid arm inward enough, so there was lateral play in the shaft and the seal did not make a positive contact with the cover.

So, the leak is fixed, and that is good news.. The bad is that now I cannot get the OD to cycle anymore! Bummer!

I remember that setting the solenoid arm on the bench was rather touchy, but I had it cycling perfectly. During the day today I went from having the OD not cycle on. I finally triggered the solenoid with the arm loose, then went under the car and slowly moved the shaft until I got the OD to just engage...and then tightened the arm. But, now it won't cycle off. I even re-loosened the arm and manually turned the shaft as far as it would in the "off" direction with no luck.

I gave up for the evening. Working under a running car gives me the willies. I think I'm going to have to pop the tunnel back off and set it like I did on the bench...
 
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CJD

CJD

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So, Dave, Craig, and especially Berry...I owe you all an apology!

I finally got my head out of my A$$ and found the internal recess. The Oring does go inside the side cover and you guys were right!

Today the tunnel came back off, so I didn't have to continue laying under a jacked car with the engine running and the rear wheels spinning. It turns out I was setting the solenoid arm correctly all along. The issue is that the friction drum is sticking, so the OD is not dropping out when the pressure was released. That was screwing me up, as I kept thinking it was the adjustment that was off.

Anyway all morning I could not get the OD to disengage. I was near ready to tear the thing back down. The manual says "if it sticks it will release when cooled down". Nope. It then says you can smack "the outside of the friction ring with a rawhide mallet". Nope. Finally, out of desperation, I took a steel hammer and tapped the ring...and it popped out of OD. Then I could easily cycle it in with the solenoid, and release with the hammer. After a few dozen cycles it finally releases by itself.

If you guys remember, this is the OD that was totally tarred up. The tranny oil went in perfectly clear, and already it is very dark, just from running the engine about an hour total. I have to assume the sticky drum is because of the remaining tar clearing all the hydraulic passages. I'll change the fluid a couple times and should (hopefully) be good to go!

Again, thanks for the help and sorry to doubt you guys!
 
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