Drum Brake Dilemma - I Think...

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ARCHINSTL
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My tercel:: Goldie is a 1986 SR5 attualmente con Weber/also owned the first T4WD in STL in late '82
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Drum Brake Dilemma - I Think...

Post by ARCHINSTL »

OK - this is probably one of my Mountain Out Of A Molehill Questions - but here goes...

The right-side adjuster works just fine after installation of all (per the FSM, one operates the parking brake lever on the rear shoe to make sure the adjuster arm actuates the star wheel on the strut).
The left-side adjuster is the problem. Upon movement of the lever, the forward portion of the strut moves 4MM+ to the front, leaving a gap as indicated on the drawing.
This is because the shoes are held further apart on the left wheel than the right because of the different distance between the compressed piston stops, and the forward part of the strut moves to take up the distance. The shoes, etc., are identical.
Hence, the adjuster arm will not operate the star wheel. It will not move far enough "down" the wheel to move it.
I can get the adjuster to actuate the star wheel if I manually turn the star wheel to take up the 4MM difference (to then match its right-side sibling). Then, it works just fine. It is just that the left-side shoes are a little further apart than the right-side shoes. Mind, I still have to adust both sides further out to get the approved distance between the shoes and the drums.
Autozone says the difference in the wheel cylinders is an accepted variance...
Is this anything about which to be concerned? Or just button it up and forget about it? Am I just addled in my dotage?
The last drum brake work I did was on Morris Minors and a Singer, and these variances just did not crop up ('course, the Singer used mechanical brakes on the rear...and neither car had anything fancy like self-adjusting brakes).
Thanks.
Tom M.
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takza
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Post by takza »

That's about a 1/10" difference...quite a lot. Seems if you can manually adjust things so the star deals will work it would be ok.

Main thing is to be sure that there is no possibilty that a piston will end up coming out of a cylinder due to too much movement.....this = a sudden loss of braking.

I found with my rear brakes that the drums were turned oversized so that the rear brake shoes only contacted on about 2/3s of the shoe sufaces...replaced the drums.
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ARCHINSTL
Goldie Forever
Posts: 6369
Joined: Sat Apr 30, 2005 1:52 pm
My tercel:: Goldie is a 1986 SR5 attualmente con Weber/also owned the first T4WD in STL in late '82
Location: Kirkwood, a 'burb of St. Louis

Post by ARCHINSTL »

I resolved this by just turning the star wheel until the 4MM+ difference was taken up, and the strut was tight in the shoe slots.
And the brakes work just great.
So - in the real world, my worrying was for naught.
Tom M.
T4WD augury?
"Oh, do not ask, 'What is it?' Let us go and make our visit."
T.S. Eliot - "The Love Song of J. Alfred Prufrock"
"Now and then we had a hope that, if we lived and were good, God would permit us to be pirates."
Mark Twain
Typrus
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Post by Typrus »

I think I saw a similar problem.
Its amazing how much those drums contribute to stopping power... When they are non-functional the car feels like you have Nike's out the door for brakes.
But then again, mine were non-functional due to spacing, so my foot travelled waaaaaay down to get anything. So Isuppose the discs weren't getting proper pressure anyway.
RIP 10-07- 1984 Toyota Tercel SR5 4wd Wagen 6 speed

RIP 04-05- 1986 Toyota Tercel SR5 4wd Wagen 6 speed

1st Terc- 1987 Tercel SR5 4wd Wagon 6-speed, Sadly cubed

1985 Tercel Standard 4wd Wagon w/ 3-speed auto, Living a happy life in Boulder last I knew
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