1969 FJ40 Brake Questions

[69 FJ40]

Hello All,
I used the search button and have been reading all day . The brake master cylinder in my 40 is leaking so I have been looking at the following options:


- Should I just replace the single circuit master cylinder?
- Should I upgrade to a dual circuit system?
- Should I do a full disc brake conversion?


I want the cruiser to be safe on the road, while keeping it close to stock as possible. It is not a daily driver and I do wheel it once in awhile and when I do I usually drive it to the trail and back. I don’t have a lot of funds to

spare so this has to be on a budget .


I am leaning towards upgrading to dual circuit with drum brakes and maybe disc in the front later down the road. I have the following questions:

• Adapter plate? (I do have a call into mark for this)
• What MC will I need to get?
• I have learned the stock lines are 9 mm, but the new MC will be 10 mm? What do I do here?
• Will this clear my stock carb? It looks pretty close (https://forum.ih8mud.com/40-55-series-tech/464213-my-single-circuit-brake-upgrade.html)
• How do I re-route the lines?
• Should I consult a brake shop for this?

Thanks in advance.

 

[7228]

you could just get a rebuild kit for the master its like $20 at sor.com. if you are looking at doing disk brakes for easy may want to get a brake booster jt outfitters have a adapter.you dont need a booster just makes stoping easyer. man-a-free is coming out with a duel res master that will bolt on but thats not out yet. im thinking i may go with the man-a-free my self but i also have a booster from a 1980 fj40 with front axel. you can get a coil of brake line from napa cheap and fitings if you want to do it your self but you will ned to get a buble flare tool as will. do you have a 1bbl or 2bbl carb my 40 has the 1bbl and it will be a tight fit. hope some of this will be help full im in the same boot as you but 3 wheel cylinders are leaking on 3 diff wheels.

 

[tyama]

Hiya, I just finished this on my '70. I would suggest going to dual circuit at the least and going to disk fronts at some time or going all the way to disks all around. I did the mini truck front conversion and put on the bigger 4runner rotors with the '96 geo metro mc & booster. It seems to stop pretty well. I left the drums in the rear for now. If you go to two circuits you'll have to do a bit of re routing on the brake lines. The simplest thing for the 9mm lines is to put 10mm ends on your lines for the dual MC and leave the rest 9mm.

Brake work is not that tough. You'll want a tube cutter, a dual flare tool (get a good one), and a tube bender.

You can get a lot of good info on the forum. Good luck!
Ty

 

[fireflyr]

I've been running the Man a Fre dual circuit master for about a year and no problems. It's abailable just not on webpage yet. I also have 9mm fittings and all I can say is save anything you remove. I used the fittings and bent new lines to separate the front circuit from the rear. I also used Posers brackets in th rear with a proportioning valve when i switched to discs. Lots of info here in FAQ and search. Good luck.

 

[fireflyr]

I've been running the Man a Fre dual circuit master for about a year and no problems. It's abailable just not on webpage yet. I also have 9mm fittings and all I can say is save anything you remove. I used the fittings and bent new lines to separate the front circuit from the rear. I also used Posers brackets in th rear with a proportioning valve when i switched to discs. Lots of info here in FAQ and search. Good luck.

 

[7228]

i thought that bubel flare is better then duel for brake lines.

 

[69 FJ40]

Thanks for the great info guys. I did see the man-a-fre setup today while searching, but price wasn't listed. Can I ask how much you paid for that setup? Oh and I have a 1bbl carb. Thanks

 

[fj404life]

Everyone trys to scare people into discs and dual masters around here.
If you are competent working on brakes you can make the stock system work dang good.
Flame suit on.

That said...if your not dialed on working on brakes...have someone who is do the work!

 

[69 FJ40]

Everyone trys to scare people into discs and dual masters around here.
If you are competent working on brakes you can make the stock system work dang good.
Flame suit on.

That said...if your not dialed on working on brakes...have someone who is do the work!

I have been driving the 40 with the single circuit for over 5 years and never had an issues with it. Always stopped true and straight. I am looking into the dual system because I think it is safer and since I have to replace the existing mc anyway. I will most likely have a reputable shop handle this, since I do not have all the tools needed. Anyone know of a good place in the sf bay are, east bay to be specific? Thanks

 

[fj404life]

Roger that...I took the ez way out and just replaced mine with a new single cyl master.
I saw the can o worms and it scared me LOL. Not sayin I can not see the benifits to dual circuts or discs...
Someday my 69 will prolly be sporting both. For now it will almost put me through the windshield.

 

[7228]

i dont mind drums. will exept when they get soaked with water. the only way i will go with a duel is if i was going to disc

 

[fireflyr]

For safety I still stand on the dual master. Drums or discs are beside the point and a whole different discussion. Flaring and bending lines is easy and you can split the circuits on the passenger side at the fitting in front of the firewall on the frame. I ran the line for the rears along the same route as the vacuum lines to the transfer. Later you can upgrade the rears using a monte carlo kit with a proportioning valve. It's all easy stuff and makes the truck much safer. I lived with drums for years and knew how to drive them. It wasn't until I let my dad drive it that I saw just how bad they were.
The industry was forced to go with the dual master for a reason. If you are driving your family around in the truck then you owe it to them.
George from Valley Hybrids came up to me at a rally and complimented me on my cruiser a few years back. He then went on to tell me of an incident where a single circuit had failed offroad and killed the guy. He was really earnest in telling me this and politely suggested that I needed to change mine. Some people may have been offended by this but not me. I knew him only by reputation but I thought it was pretty damned cool that he would take the time to look out for my safety.
I fly fire fighting helicopters for a living and have had 3 total hydraulic failures in the past 8 years, the last almost put me into the side of a mountain. Our aircraft have some of the best maintenance in the industry but stuff still breaks. Give yourself every advantage you can.

My two cents worth.

 

[shelfboy1]

seems kind of funny now ,when i started driving fj40,s there were no disc brakes just single circuit drums .no one i remember ever had a wreck from this.

 

[fireflyr]

seems kind of funny now ,when i started driving fj40,s there were no disc brakes just single circuit drums .no one i remember ever had a wreck from this.

Very true, but now they are 40+ years old and doing things they weren't intended for with way more horsepower, more weight and much larger tires.

The Wildwood dual master that Man A Fre sells was originally built for the hot rod crowd. I think they make a better connection sometimes with the fact that going faster also requires stopping better.

A good set of well adjusted drums are a beautiful thing, and the single circuit stops just as well as a dual, it's the redundancy that the dual circuit brings that's important.

 

[fj404life]

Switching to a dual circut would be high priority for me if I drove faster than 40mph.
Small town...not much traffic and my 40 does not see much highway at all.
Totally agree that its a good thing...and I wish Toyota used 10mm fittings in 69 would make for a much easier swap.

 

[cjgoode]

I can deal with drums, but went with front disk since the first replacement axle I found had them. But I 100% was going to replace the single circuit with a dual circuit system. If 1 line fails on the single the whole system fails, seems like a no brainier to go dual circuit. After seeing how brittle the original 50 year old lines were I am glad I replaced 100% of the brake lines as well. I would recommend dual circuit and all new brake lines, simple and cheap and well worth the safety.

 

[todt]

Fireflyr thanks for the tip with the Man-A-Fre setup. Got mine Fri.

hijack over.

 

[69 FJ40]

For safety I still stand on the dual master. Drums or discs are beside the point and a whole different discussion. Flaring and bending lines is easy and you can split the circuits on the passenger side at the fitting in front of the firewall on the frame. I ran the line for the rears along the same route as the vacuum lines to the transfer. Later you can upgrade the rears using a monte carlo kit with a proportioning valve. It's all easy stuff and makes the truck much safer. I lived with drums for years and knew how to drive them. It wasn't until I let my dad drive it that I saw just how bad they were.
The industry was forced to go with the dual master for a reason. If you are driving your family around in the truck then you owe it to them.
George from Valley Hybrids came up to me at a rally and complimented me on my cruiser a few years back. He then went on to tell me of an incident where a single circuit had failed offroad and killed the guy. He was really earnest in telling me this and politely suggested that I needed to change mine. Some people may have been offended by this but not me. I knew him only by reputation but I thought it was pretty damned cool that he would take the time to look out for my safety.
I fly fire fighting helicopters for a living and have had 3 total hydraulic failures in the past 8 years, the last almost put me into the side of a mountain. Our aircraft have some of the best maintenance in the industry but stuff still breaks. Give yourself every advantage you can.

My two cents worth.

Agree! This is why I want to switch to a dual circuit. How much did the man-a-fre system cost? Can you post some pics of where you made the connection for the rear? Thanks

 

[fireflyr]

Fireflyr thanks for the tip with the Man-A-Fre setup. Got mine Fri.

hijack over.

It looks like the adapter part # is wwmcspcr and was $45. The master is part# 260-7563 and was $146. This was a year ago.
I was wrong about the routing. I just went over the firewall and down to the frame then back to the rear.
The straight thru fitting that's next to the starter on the top of the frame got moved forward and replaced the T or 3 way brake fitting that supplies the right front brake. This way you don't have to try and come up with a 9mm plug.
The front circuit ends here.



This is why it is important to save the 9mm fittings. You can flare it on to a new line so it goes to the left front brake from your master.









Here you can see where the rear line comes off the front of the master thru the proportioning valve then up and over the firewall and down to the frame, then back to the rear axle. You can flare in the proportioning valve when you go with discs in the rear later.

 

[landcrusher909]

https://forum.ih8mud.com/40-55-series-tech/464213-my-single-circuit-brake-upgrade.html Since I did this I have to say I love it. I am still running drums all the way around and its working out Perfect ! In fact Georg ( orangeFJ45 ) at Valley Hybrids is now selling the complete adapter with the extension for the brake rod so it bolts right up. I picked up a core master and bought a reman from Napa auto parts also you can do search for the 10mm fittings that adapt to the 9mm lines. If your still running a 1barrell clearence should nit be a problem Good Luck with your project