Today i pulled the rear wheels off my T to check the bearings and grease since they haven't been off since i rebuilt the rear-end last year. To my surprise the outer bearings had almost no grease on them although i packed them thoroughly when i put it together. No grease escaped past the outer seals into the drums, but the grease did find its way into the diff and mixed with the gear oil. When i assembled it i put in the new outer neoprene seals and a F/P pinion bearing kit and now it seems like it may be sealed so well that it needs to be vented in some way. When i first ran it after the rebuild, i ran it on jack stands for about an hour, and when i pulled the plug to check the oil level there was a definite suction sound. Anyone else out there have this happen to them, and what was your remedy? Thanks
OK. I'm going to make some assumptions here. First : I'll assume you used a decent type grease. Second guess is : it was heat that made the grease melt away. When you pulled the plug and heard the sound did it have a chance to cool off?
Because cooling & therefore shrinking of trapped airs
volume is the only way I can imagine a vacuum forming. Thirdly : are you dragging the emergency brakes and creating the heat in the first place? I'm not really sure but can you actually seal a T rear that well?
Charlie, i have been using a high quality grease, the same i use for my u-joint with no ill effects. And my E-brakes are set correctly and i only use them for what they were designed for, parking, not braking. Its a mystery.
Have you checked the mystery suction control module setting ?
Your speculation about a pressure change (the sucking sound) may have some merit. Somewhere I remember seeing a picture of a pumpkin with an air vent on top. But ......... there have been lots of Model T's in the world and Ford apparently never thought a vent was necessary. That leaves the possibility that your modern seals are preventing normal venting in such a way that the grease is sucked into the pumpkin.
I had a similar mystery that puzzled me for some months. I had a pump type hand soap dispenser by my sink that kept emptying itself. Couldn't figure it out. Then one day I noticed that the sun was shining in the window and onto the dispenser bottle every afternoon. When I moved the bottle out of the direct sunlight, bingo -- no more soap escaping. So I drilled a small vent hole in the top of the soap bottle and now it sits in the sun without a problem.
Thanks Burger, i only have one control knob on my dash...do i push or pull, or spin it to achieve suction?...these newfangled devices have me thoroughly perplexed.
Dick, i am thinking that you are totally correct when it comes to heat and pressure in a confined space, and ultimately a vacuum situation like mine.
You could always drill and tap a small hole for a vent fitting near the top of one half of the rear axle housing.
My 1919 Touring came to me with a small vent hole drilled in the right side torque tube at the top near the brake backing plate.
Keep looking John. It's the big, silver box with all the lights and buttons on it. Gotta be there somewhere !
Mine was in the corner of that round room.
Darren Wallace added a vent on his 1915 T rear axle & posted pictures here.He was having grease issues & the vent cured them.
Speaking of grease --
After doing some work on my wife's Model A, I decided to check the front wheel bearings on my 19 T since I haven't looked at them and the car was in storage since 1964.
They were covered with black grease and my wife offered to put them in her dishwasher. They are now super clean and sparkle just like our wine glasses.
I didn't want to get them dirty again so I rubbed them with clear mineral oil before reinstalling them.
I am thinking I should do the same thing to the rear.
That's some wife you have, Fred, she's a keeper!
I thought cleaning car parts in the dishwasher was strictly a bachelor thing...
Yeah, when I have to clean a really greasy or dirty car part I just use my wife's tooth brush then I make sure I just kiss her on the cheek for the next week.
Ya I know!
The Jim Beam bottle is almost empty so she told me I had to finish it tonight so we had room for another.
My favorite wine is on sale and she wants me to geet two cases in the morning.
The Kaluah bottle is down by 2/3 and she thinks we need more.
I accompanied her on the shopping trip to BJs today and we got ribs for smokin.
Tomorrow I will take her Model A transmission to a friend to be rebuilt and order new kingpins for my T from Langs
She likes guns and carries when appropriate.
I can't do better!
Forgive me if it's been touched already above, (not gonna read it all...), but I didn't see you mention anything about inner seals in your original posting. What about those?
Jerry, i installed new neoprene inner seals on the outer bearing. I didn't phrase in very well in my original post.
Wait a sec...you installed neoprene inner seals on the bearings? Where did the bearing grease go? It should not have mixed with the diff lube at all with them correctly in place.
Charlie, yes the new inner seals are still there and look as new as the day i installed them. But Abracadabra, my grease has found a new home in the diff. Very perplexing how it made its way there in such a short time.
That's what I'm having a problem with. Was it overfilled as in engine oil running back into the diff and diluting it? As to the vacuum business I don't see that pulling it off the bearings. Couldn't possibly be strong enough for that. I dunno. I'm still thinking heat dissolving it then cooling off and creating a slight pressure differential. In the differential. LOL.
Charlie, the engine has never been over-filled, and the little bit of grease i lose out of the ball cap area is like brand new in its consistency. When i sucked out the mixture from the diff, it was absolutely 600 and bearing grease, no oil to be found....Its a head scratcher to be sure.
That doesn't say much for the new neoprene seals, does it ? I'm having trouble visualizing how the modern seals could sustain an air pressure differential and yet allow grease to pass by so quickly.
I'm not doubting your finding, just wondering how it could happen.
Dick, I'm doubting myself as well, it seems almost impossible to get that much grease to flow through the seals, but where did the bearing grease go, and why is my diff contaminated with bearing grease? I have all the bearings re-packed and the diff filled to the proper level, will drive it a bunch then recheck to see if i need psychiatric help or not.
Dick Fischer - THANK YOU for the "leaking, oozing soap dispenser problem" fix-it suggestion. Our soap dispensers have been driving me nuts for years.
One oozes out when the hot water heats up the shower stall and the dispenser making the soap leak out, run off the shelf and down the wall.
The other one collapses as the soap pumps out and I have to frequently open the top to pop it back.
Don't know why I never thought of drilling a hole.
Honestly, that is the BEST piece of info I learned on the forum today:D
Not that the rest isn't great (I'm dismantalling and dressing my front spring and mixing up slip-paint tomorrow).
But that soap thing really makes me crazy !!!! No more.....Problem solved :p
Your experience is new to me. Have used the modern seals at the inside of the outer Hyatt, behind the Hyatt sleeve, and the neoprene and 0-ring outer cap seal over the axle housing opening. No issues in many thousands of miles.
One thing you might try. After your normal 200 mile twisting of the grease cup at the outer Hyatt bearings, remove the cap, clear out the grease so the opening is cleared, checking with a probe too. Then leave the grease cap off. If a cover is needed, cut a piece of wire screen and twist tie that over the grease cup.
Now you have a 'vent' and can check to see of that helps.
Curious on how you found grease in the axle housing, did you remove the oil drain plug and suck oil out and grease came too? Normally the oil level is down a tad from the drain opening, and should just drip out a little bit if full. If pours out, too much oil in the rear end.
I have worked on and setup differentials for years in on road and off road racing applications. My theory for your differential John, is that all modern differentials have a breather vent in the Gear case. Since there is a lot of heat generated in the gears the pressure that builds in this small area has to go somewhere. In the case of the Model T there are no vents at all and relies on the looseness of its construction to relive this pressure, and then the Vacuum that comes with the cooling off.
I think John, that when you rebuilt your differential last year that you did such a good job in sealing that this Vacuum is pulling the grease back into the housing a little bit every time the housing cools off. This condition might be even more in the winter months.
I suggest that before you tear your differential apart that you install a vent in the center section in order to prevent vacuum from occurring.