Ball bearing size ???

[BobT-47P15]

Does anyone know the size or diameter of the ball bearings found in

the front seat adjustment tracks for two door cars?

I'm asking in regard to a 46-48 Plymouth P15......but I suspect

they are the same size in all the brands. They are captive

between the lower and upper halves of the adjuster, to make

the seat move smoothly. They can escape somehow, as I

discovered on my car.

I was thinking that if a person knew the size, replacements might be

found at a bearings dealer.

[58prostreet]

I had to rebuild mine on my '52 Dodge. There are 2 sizes, 5/8 and 5/16. Can't remember how many of each. I got mine from local bearing house.

Had to bag of each, but was not a budget buster.

Bob

[BobT-47P15]

Thanks, Bob.

[Big_John]

If you have the size, try McMaster Carr. They seem to have everything in their catalog.

[rockable]

While on this subject, I have two questions.

How do you separate the lower slide from the main frame to facilitate installation of these balls? Do you have to remove the stop that is riveted to the frame?

Also, how many of each size is required per side?

Thanks.

[DonaldSmith]

From an old post of mine, sometime last year (?) via "Seat Track" search: (I'm surprised the other Don didn't scold you for not searching this in past threads first.)

"Description of front seat track repair:

"The track on each side of the seat is formed from two heavy gauge pieces, which when placed together form two outer races for small ball bearings and a middle race for large ones. It works like a drawer guide.

"The upper piece has three recessed bolts for attaching the seat, and the lower piece is riveted to the base. (I replaced the base, so I drilled out the rivets.) The upper piece rides over the large race and one small race.

"The lower piece hooks over the upper piece, so that the upper piece rides under the other small race. There are two large balls in the large race, and two small balls in each small race. Travel of small balls limited by indentations in track. Travel of the large balls is restricted by the heads of the bolts for the seat.

"Disassembly:

"Remove the lever that goes from the handle on the side of seat to the latch under the track. Drill out the rivet that connects the lever to the latch. (I forget why I had to do this.)

"Slide the track toward each extreme position, and push out the upper bolts at the ends, making room for the large balls to come out. (If the large balls do not come out, drive the large balls to the center of the track, to provide slack for popping out the small balls. (A 3/8 drive extension works well for this.)

"The small balls should be visible in their race. Use a large screwdriver or similar tool to pry the tracks apart and pop the small balls out. With the small balls out, the pieces will separate, releasing the large balls.

"Assembly: (It’s sort of reverse of disassembly.)

"Grease the race surfaces of the track. Grease the four small balls to hold them in place. Slip the two pieces of track together. Tape them, so they won't separate. Drive a large ball in each end. Slide the track toward each extreme, and install the seat bolts.

"Draw the seat bolts home with nut and washer, so that square end of the bolt fits in the square hole. (I used small bolts to replace the rivets to the base. For some reason I left the two end bolts out until the track was otherwise reassembled.)

"I hope this helps."

I home this helps.

[BobT-47P15]

Thanks Don. Nice explanation.

[Don Coatney]

(I'm surprised the other Don didn't scold you for not searching this in past threads first.)

Why did it take you 13 hours to post this:rolleyes:

[BobT-47P15]

Don C, I suspect not everybody lives on this forum like I tend to

do. (Just ask my wife.)

Any snow yet in the 'boro???

P.S. Don't know when will get to Smashville again.....sold the condo.

[Don Coatney]

There is a dusting of snow on the ground this morning.

[rockable]

Thanks, other Don!