Hi all,
I'm writing this from work as I stayed behind at 6pm to quickly replace the rear brake shoes on my Escort (1997/R 1.8 16v Ghia X 5 door hatch, no ABS). I'm quite mechanically adept but haven't worked on drum brakes in about 15 years. I am using a Haynes manual for guidance.
I have changed the offside shoes but when I refit the drum to the hub, the drum will only rotate freely through 180' before stopping with a clonk. When turning the drum the other way the same thing happens. I have figured out that the leading shoe is slipping downwards when I refit the drum, almost to the point that the top of the leading shoe has slid completely off the piston.
I've checked, double checked and triple checked, and it appears I have assembled the brake shoes, springs, clips etc correctly. The handbrake is adjusted right off and the self-adjustment mechanism is set as far in as it will go, to prevent the drum from fouling the shoes on refitting.
What am I missing? (Apart from my dinner!)
Many thanks in advance.
Dave TD.
Edited by Dave_TD {P} on 20/11/2008 at 22:44
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Dave
Stopping with a clonk of hitting something solid, or suddenly tightening on to the friction surface.
Are the shoes all the same, in respect of the position of the linings on the shoe, or are they two distinct pairs?
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Are the shoes all the same
The leading shoes seem to be symmetrical, the trailing shoes are identical to each other apart from the brackets for the handbrake cable point in opposite directions.
The leading shoes have much more friction material on than the trailing shoes, I gather this is normal.
The old shoes... the trailing one was barely worn at all, and the leading one has worn out-of-round, with half thickness material at the bottom tapering away to nothing by 3/4 of the way up, with score marks on the metal at the top 1/4 (hence why they are being changed). Could it be a problem with the backplate or the piston?
Dave.
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OK; they seem difficult to get wrong - have you stripped the other side yet?
If not; compare the spring positions side to side.
Back in 20 mins.
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have you stripped the other side yet?
Not yet, just going back down to the workshop to do so now. I may be some time...
Dave.
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Have you stripped the near side?
If not, take the N/S drum off, and look very carefully at the layout, and exactly which hole each spring end hooks over. Then, make sure you have assembled exactly the same layout on the driving side. Don't strip the N/S until you're sure you've fixed the O/S.
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Thanks NC.
I've just stripped the NS, in about a fifth of the time it took to initially do the OS! The springs appear to be the same (mirrored)... but the NS shoes are much cleaner and NEWER, with negligible wear and no sign of anything being off-centre.
Maybe the OS has been a can of worms long before I bought the car?
Dave.
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The springs appear to be the same (mirrored).
That's odd, because for the shoe to slip it usually means that something isn't assembled properly. Sometimes, you'll find the springs aren't symmetrical, but the hook is handed, and even if the spring hook ends are in the right holes on the shoe, the body of the spring then pushes the shoe off.
Is the lower spring in front of, or routed over the top of the lower shoe anchor on the back-plate?
Edit - Forgot to add, do any of the springs on the O/S look to have stretched? Do they have gaps between the coils where the N/S spring is tight.
It's a good 5 years since I've had one of these apart, so, I'm working from very rusty memory!
Edited by Number_Cruncher on 20/11/2008 at 23:24
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Ahhhhhhhhh...........
Just been back down for another look, and yes indeed the bottom spring has the coil near the front of the car on the NS, but near the back of the car on the OS. I was only copying the Haynes picture!
I'll go and swap it round, which may well entail taking the whole shebang off again.
Dave.
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Dave
Back again; all that mention of food created a need for drive-through...
Was the strangely-worn front shoe on upside down? When shoes are on correctly, any asymmetrically positioned lining should appear that the forward rotation of the drum has slid the lining on the shoe.
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The reason the leading shoe tapers is normally a result of the combination of the adjusters seizing and the free play being taken up on the parking brake adjuster.Does the h/brake come up to the limit of it's travel and does it seem to jerk as you pull it
up. If this is the case you'll probably find the adjusters are worn and will need replacing.
Also it's very likely that the h/brake cables have stretched to the limit of their adjustment.
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Long shot. The retaining pins and springs have been re-fitted have they, the lavk of these can cause the shoes to tip rub on the drum and push the show down. Regards Peter
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