Thing brakes

[gunnerjoe]

I just obtained a '74 Thing in excellent condition. The brakes, however, are scary!!

Is it possible that the dual circuit master and/or one or more of the slave cylinders are stuck or malfunctioning? How would I check this?

Thank you...

[Steve Arndt]

Yes that is possible.

What are the symptoms your thing is exhibiting?

[Marc]

Check the fluid level in the remote reservoir in the trunk. If both sides are near full there's no severe leakage. The most common leaks are from the wheel cylinders (backing plates will be damp), the main brake line where it curves behind the pedal cluster (look for fluid under the floormat), the stoplight switches, or the master cylinder itself (fluid that leaks out into the front bulkhead area eventually finds its way to the drain hole in the bottom of the tunnel just ahead of the front trans mount).

To really know what's up you've got to remove all four drums (and know what you're looking at)...but for a more incremental approach, start by adjusting the brakes - assuming the adjusters aren't frozen; if they are, correction will require (guess what?) drum removal.

Thing front brakes are essentially the same as `66/`67 Beetle although the backing plates are different; the rest of your braking system is basically the same as a `74 Beetle except for the unique Thing rear drums. "Authentic" brake linings will have a 181 part number (harder lining?), but the Sedan parts fit and function OK.
Front brake flex hoses are 390mm long (113 611 701D). Rears are the 210mm 113 611 775E.

[doc]

You might also try:

Jack up the front so wheels are off ground. Each wheel should spin freely when turned and not make any scraping noise. Have somebody step on the brake while you spin wheel. It should stop - solid. No bad noises. Do same on rear wheels. Pedal should be solid and come firm fairly high when depressed.

This should help you identify what's wrong. Then start following Marc's outline. You'll find something. Adjusting the brakes via the star adjusters has provided many a cure. WD-40 might be your best friend. The hubs could be hard to pull off if you can't back off the adjusters.

doc

[gunnerjoe]

Tonight I tried all the lights on the Thing. Found that neither brake light works. Further indication of a master cylinder problem? BTW, the brake pedal is hard with no fade. It takes a LOT of pressure to stop, however...

I will try the adjuster fix first but feel that I need to get into the braking system in some depth.

[Ol'fogasaurus]

Lately there have been several problems with stiff or limited working brakes (including me) that have ended up been fully or partially tied to dried out/swollen soft lines. Check to see if there is a date on them and also see how flexible they are.

There is a definite limited life to them so as part of your going through the brake system don't forget them.

Lee

[Marc]

http://www.speedyjim.net/schem/3brake.gif

If the pedal is high & hard it's unlikely that there's a M/C problem (I'd suspect frozen wheel cylinders or bad flex hoses first). However, another classic cause of high/hard pedal is insufficient M/c pushrod freeplay, so do check that the brake pedal moves ~⅛" before any resistance is felt. If not , the #1 cause is a pebble caught between the "tail" of the pedal and the stop plate on the floorboard.

There's an inline connector between the M/C wiring harness and the main harness that heads back through the car...look for the black/red-stripe Term 81 wire there - if you inject 12V power there the brakelamps should light.

The black wire going to the M/C (Term 82a) should be hot with the key on....if it isn't, the brakelamps have zero chance of functioning.