I'm getting ready to pull the driveline in my 40 and will need to reseal the overdrive. Does anyone know if you can purchase shaft seals based on dimensions? I'm sure the input seal is hard and leaking and it is not made anymore.
Resealing a Fairey Overdrive (1 Viewer)
- Thread starter Von Hayek
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Living in the Past
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Which overdrive? 8/80 the Fairey overdrive changed completely when the split transfer case started. If the early one I didn't realize the input seal between the transmission and transfer case was different than without the overdrive.
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This is for a 78' one piece, and you're absolutely right. Thanks for straightening out my thinking.
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Bart,
Somewhere in the bowels of my shop I have a special, thin wall, tapered collar that an old friend gave me. The OD on the collar matches the OD on the input shaft of the overdrive. During re-assembly, you put the collar through the front of the t-case...no seal installed yet...then put the snapring on the collar. You feed the overdrive in from the back, loading the PTO spacer shims and input gear onto the overdrive through the side access.
Then with patience (cause you only get one shot)you slide the snapring off of the collar and onto the input shaft until it reaches the groove it belongs in. There just isn't enough room to get a snapring pliers through the front of the tcase and open the snap ring up that way.
To all: I realize this tech is a little esoteric. But if you recognize the value to the forum search, I'd appreciate you hitting the like button.
Somewhere in the bowels of my shop I have a special, thin wall, tapered collar that an old friend gave me. The OD on the collar matches the OD on the input shaft of the overdrive. During re-assembly, you put the collar through the front of the t-case...no seal installed yet...then put the snapring on the collar. You feed the overdrive in from the back, loading the PTO spacer shims and input gear onto the overdrive through the side access.
Then with patience (cause you only get one shot)you slide the snapring off of the collar and onto the input shaft until it reaches the groove it belongs in. There just isn't enough room to get a snapring pliers through the front of the tcase and open the snap ring up that way.
To all: I realize this tech is a little esoteric. But if you recognize the value to the forum search, I'd appreciate you hitting the like button.
- Thread starter
- #5
Are you taking about this?Bart,
Somewhere in the bowels of my shop I have a special, thin wall, tapered collar that an old friend gave me. The OD on the collar matches the OD on the input shaft of the overdrive. During re-assembly, you put the collar through the front of the t-case...no seal installed yet...then put the snapring on the collar. You feed the overdrive in from the back, loading the PTO spacer shims and input gear onto the overdrive through the side access.
Then with patience (cause you only get one shot)you slide the snapring off of the collar and onto the input shaft until it reaches the groove it belongs in. There just isn't enough room to get a snapring pliers through the front of the tcase and open the snap ring up that way.
To all: I realize this tech is a little esoteric. But if you recognize the value to the forum search, I'd appreciate you hitting the like button.
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- #6
I'm starting to get a bit leary of pulling this thing apart.
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That’s nothing compared to what you are going to feel when you look inside the input shaft.
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Geez Mark, like hanging out with Debbie Downer...That’s nothing compared to what you are going to feel when you look inside the input shaft.
dmaddox
SILVER Star
Going to add this to my list of pickup lines, actually. Poetry. Kidding aside - the idea of using something like Mark is recommending is genius. Couldn't you use a piece of pipe that has the same OD and go about it in a similar fashion? It's what I'd try!That’s nothing compared to what you are going to feel when you look inside the input shaft.
Good luck
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Same problem the McNamara gear was designed to deal with in the FJ62, but by a factor of 8…with no remedy.Geez Mark, like hanging out with Debbie Downer...
Honestly, anyone with a 74-80 4speed Fairey should be prepared for the very real possibility of abandoning the unit before they take it apart. The splined contact surface was marginal when new.
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- #11
It has been functioning just fine and the overdrive is a very real benefit, but it has been leaking madly. I was hoping to remedy the leaking and retain it.
That said, I know that in the many years since production has ceased that long-term viability is near zero. I was just hoping to put it off.
Living in the Past
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You are correct on the very small spline section piece that rides on the transmission tailshaft. I have a H41 with a worn tailshaft I thought installing an OD but the H55F is a better option. If a second five speed would have been offered with the H42 gear wouldn't even thing about a Fairey OD. The 8/80+ Fairey OD does not allow a PTO to be used.
I have a rainy day plan.
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- #13
All went well, and it is back in the truck, but I believe I have a mistake to fix. When resealing it, we did not take into account the ports for the sharing of oil between the overdrive and transfer case. I am assuming that a PTO unit mounted here would be designed to use the same system. The paper gasket between them was more-than liberally-coated with The Right Stuff and clogged at least one hole.
I managed to clear the small hole at 4 o'clock in the middle of the gasket surface area. Is the hole at 11 o'clock in that recess supposed to be a breather?
I managed to clear the small hole at 4 o'clock in the middle of the gasket surface area. Is the hole at 11 o'clock in that recess supposed to be a breather?
Hey Mark , I have an early fairey overdrive and like many the drive sleeve splines are well worn (50%) . Asking if you knew of a remedy for this ? Are you aware of anyone remaking them ? Any comment from you would be greatly appreciated. Best regards from Aus.That’s nothing compared to what you are going to feel when you look inside the input shaft.
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1. I don’t know of anyone who is making or remaking parts for them.
2. I have a box of miscellaneous used parts for the Fairey that may or may not include a less worn 10 spline input shaft, which is what I would refer to as an “early” unit.
3. Your picture looks like a 16 spline; I am pretty sure that the ones I have of those are just as bad as yours, possibly worse.
GLWS
2. I have a box of miscellaneous used parts for the Fairey that may or may not include a less worn 10 spline input shaft, which is what I would refer to as an “early” unit.
3. Your picture looks like a 16 spline; I am pretty sure that the ones I have of those are just as bad as yours, possibly worse.
GLWS
I would appreciate it if you could have a look for a 10 spline drive sleeve. The one I have came from a 4speed with the early type transfer case , I assumed it would fit but it does not due to the gearbox main shaft spline difference.
Do you know if other than the drive sleeve , is the rest the same?
I need a drive sleeve anyway and would prefer a 3spd one.
Thanks for your reply and I hope you can help me out with the correct 10 spline drive sleeve.
Living in the Past
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What transmission are you running? The spline piece has to match the transmission. The actually input gear has to match the transfer case. 4/75 the tooth count switched from 29 to 31. The 9/73-4/75 with a four speed actually have the narrower high range gears like three speed but the higher geared low range like the four speed. Because the way the Fairey OD works it's possible to use either transmission on either either transfer case. If you have an early four speed it's possible you have the original transfer case. There is a date code on the right side of the transfer case. Has a number followed by a letter. Then some more numbers. First number is last in number in the year made. Letter is the month. A is January, B is February and so on. The other numbers is the one made that month.
The transmission is a 3 spd floor shift, the main shaft has 10 teeth that drive the PTO and transfer gears.
The date code on the transfer case is saying December 1971 which is correct for the vehicle I removed the transmission from.
My FJ45-31644 is August 1967. Im really holping you can put ypur hands on a drive sleeve for me here.
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If you are thinking to modify a four speed unit, keep in mind there are other variables. The Fairey housing occupies the space where the transmission tailshaft bearing would have been. So, the diameter changed corresponding to the diameter of the different support bearing it replaced. Also the spacers behind the input gear changed to match the different thickness of the gear.
Unless you can make arrangements with someone else stateside to deal with shipping, it won't make a difference if I find a shaft because I don't ship out of country.
Unless you can make arrangements with someone else stateside to deal with shipping, it won't make a difference if I find a shaft because I don't ship out of country.
Thanks for the caution Mark, you are correct. The 3spd support bearing is 72mm od and the 4spd 75mm od. Milling the 3spd transfer case to suit the larger bearing seems possible although I do have the 4spd transfer case that the overdrive was removed from, if i used the 4spd transfer the support bearing size problem would dissapear along with the 29/31t drive gear difference, the known (at least for me anyway) remaining problem would be the drive sleeve to suit my main shaft notwithstanding the further hope that the synchro hub etc on the 3spd drive sleeve is the same as the 4spd drive sleeve.
Of course if you had an overdrive to suit a 3spd...........................................
I can say I am looking forward to the happiness I will get from solving the problem that my desires have created. If you do have the 10t drive sleeve and allow me purchase local shipping is fine, I have friends and family in the USA. Thanks for your interest and your help in this.
