1969 Fj40 Brakes (1 Viewer)

jdb

Joined
Sep 9, 2005
Messages
4
This is the continuing saga of my attempts to bring back to life my 40 from the scrap (or crap) heap.

This has been a project for the last 2.5 years and still not on the road. I am at the boiling point ready to send it back to the crap heap. Finally got the body work 95% completed, engine, trany, etc.

Have taken it for a few spins in the yard and brakes worked. I purchased a new master cylinder as the original leaked brake fluid on the inside of the firewall and peeled the paint right off (OUCH). I bench bled it and set the new master cylinder on and bled the system. At first all seemed OK in my yard adventures until the brake pedal began to go to the floor with no resistance (now thats excitement) ! I again bled the system etc, etc... still the same problems. I put 4 quarts of brake fluid thru the system without results. I noted that when the brakes were pumped up you can get pressure and acuate the brakes. Upon releasing the brake pedal you could actually see the brake fluid "gurgling" back into the master cylinder reservior, and depressing the brake pedal would result in no resistance. I finally had enough and took the 40 to a mechanic in town and he charged me 60.00 to tell me some of the cylinders were frozen. I brought the 40 home and checked and they did appear frozen.

I ordered all new wheel cylinders put them on myself, bled the system, and the same symptoms persist. I have had this jacked up in the shop for a month. By the way, no leaks from the lines, etc exist.

So now I am ready to get out the torch and permanently send it to the bone yard! I intended to restore it and have fun wheeling, not have it constantly broke down and wrenching on it.

Does anyone have any ideas before I light off the torch ?
 
Joined
Sep 10, 2004
Messages
954
Location
coastal empire
First... make double sure you are not leaking BF anywhere. Check all unions and inside your drums for puddles of fluid.

Adjust your shoes all around per FSM or Haynes. Also read the troubleshooting section of the FSM and Haynes. It'll tell you what to look for.

Remember, these are drum brakes and have a much different feel than power assisted disc brakes.

It si also a good idea to make sure you have some lining left on the shoes and your drums are true. If you are not sure, bring the drums to the garage and have them turned.

When adjusted properly, drum brakes work rather well but you need to get used to them. Good Luck./
 

jdb

Joined
Sep 9, 2005
Messages
4
Forgot to mention that I also added new shoes along with the new master and 8 new wheel cylinders.

When I push the brake pedal it goes completely to the floor with no perceptible change in speed. The only way to get stopped is to pump them up with several strokes administered to the brake pedal in rapid succession. As soon as you let off the brakes and let them rest for approximately 5-8 seconds you have no brakes again and must repeat the process to stop(pumping the brakes).

Thanks for the feed back trekker.

JIM
 
Joined
Feb 24, 2004
Messages
1,628
Location
Monroe, WA
 
 
 
Adjust adjust adjust. Adjust them so the shoes are touching the drums and you can't turn the tire by hand anymore, then pump up the brakes until there's plenty of pressure and stand on the pedal. Then go back and adjust the shoes until they're touching again. Keep going until stepping on the brakes no longer produces a change. Then back off the adjusters until you can turn the tire by hand, but can still feel the shoes dragging just a bit. This takes a little 'feel', but you'll learn to match the drag on all 4 tires so you can stop in a straight line.


Then drive it around the block and adjust them again. On new shoes, I prefer to set them up a little on the tight side since the shoes will need to wear in to fit the surface of the drum before a decent contact pattern is established.
 
Joined
Nov 21, 2004
Messages
421
Location
Texas
 
I had the same problem on my 40 (same as in exactly!). Ended up being that the Push rod for the master cylinder was adjusted too short. Adjust it out in half turn intervals until you have pedal.

Chris
 
Joined
Jun 11, 2004
Messages
1,042
Location
high desert, ca
There shouldn't be a push rod adjustment on the 69 that would do that, need a booster for that. You replaced it with the original master cylinder, with only one plastic reservoir? Brake adjustment is something that a lot of new cruiser owners take for granted. They are not as simple as adjusting the drums on your old chevy or ford, or something of the likes. Sometimes, even on newer brake cylinders, the adjusters can freeze up very tight. Like bust out the air chisel tight. These can make you think you might be adjusting them, or you can even end up turning the wrong way because a manual told you so (experience). You have two adjusters per wheel, so go play with them. My fj55 was a triple pumper when I got it. Fun.
 
Joined
Feb 7, 2005
Messages
1,643
 
I had a similar problem with drums: No pedal unless I pumped them up. Then, they would hold pressure just fine.

Turns out that the new M/C I had purchased and installed was too small--the wrong inner diameter--so it took extra pumping to fill the cylinders and create the appropriate pressure. Check your hydraulics' specs against what was factory on your rig. That goes for the new wheel cylinders as well.
 

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