Will Brake Fluid Come Out Of This Port? 1965-1967 F-250 Upgrade

[chris401]

Don't have the brake warning switch for the 1967 F-250. Can I leave that port open for a trip to the parts store or does the switch also hold back fluid?

Thank's

[GJCAT427]

Ya it will push to one side or the other the minute you put pressure to it. I would try an old switch to keep it from moving. while you get the new one.

[chris401]

Ya it will push to one side or the other the minute you put pressure to it. I would try an old switch to keep it from moving. while you get the new one.

I'll have to plug it off for now. Left the NOS warning switch and 67 brake pedal in Texas. All of this is actually going on my 1965 F-250. Easier ways to convert to a dual pot but this is my way. I haven't rebuilt a master cylinder since college, I was thinking about drilling out the new master cylinder and taping it for my 65 type switch. Been done successfully? Wouldn't have to fool with a T in the brake line or a pedal mounted switch.

[Falcon67]

I'd just buy an appropriately set up MC because they all bolt up the same, if there's a year that has that.  You should get a fitting that threads into the switch and use the tail end of an appropriate sized drill bit and some JB Weld to make a holding "tool" to keep that switch centered.  You'll play hell getting it back on center without disassembly and if it shuts off one end, you'll have way less braking than you think. 

[chris401]

I'd just buy an appropriately set up MC because they all bolt up the same, if there's a year that has that.  You should get a fitting that threads into the switch and use the tail end of an appropriate sized drill bit and some JB Weld to make a holding "tool" to keep that switch centered.  You'll play hell getting it back on center without disassembly and if it shuts off one end, you'll have way less braking than you think.

No master cylinder that I am aware of unless I use a latter Ford with cruise control. I do not follow you on the rest. Drilling and tapping isn't an issue for me. It will require a straight thread to flair adapter. The switches on these are always lower than the fluid level so there won't be enough trapped air to hinder braking.

My question in success was based off of the plunger and spring locations. Can't remember if the return spring is at the tail end of the plunger or if it sits on a shoulder up further from the end. I didn't want to tap into that area.

[chris401]

I found the warning switches are the same till 1996. I took one off of the neighbors truck to get rolling. Something I didn't expect was the improved breaking. The dual pot 1967 master cylinder must be a larger diameter compared to the single pot that was on my truck when I bought it. I decided to just make some brackets for the 67 brake light switch. I'll get on that tomorrow.

[Falcon67]

I'd just buy an appropriately set up MC because they all bolt up the same, if there's a year that has that.  You should get a fitting that threads into the switch and use the tail end of an appropriate sized drill bit and some JB Weld to make a holding "tool" to keep that switch centered.  You'll play hell getting it back on center without disassembly and if it shuts off one end, you'll have way less braking than you think.

No master cylinder that I am aware of unless I use a latter Ford with cruise control. I do not follow you on the rest. Drilling and tapping isn't an issue for me. It will require a straight thread to flair adapter. The switches on these are always lower than the fluid level so there won't be enough trapped air to hinder braking.

My question in success was based off of the plunger and spring locations. Can't remember if the return spring is at the tail end of the plunger or if it sits on a shoulder up further from the end. I didn't want to tap into that area.

What I mean is to take a brake fitting that threads into the switch where the warning switch contact would go.  Then find a drill bit that fits the home in the fitting.  If the switch is centered, thread in the fitting, insert the azz end of the drill bit and JB Weld it in place.  That will hold the switch in the neutral position while you work the rest of everything out.  No drilling or tapping involved.  My experience with these switches is that once it gets off center, you will need to remove it, disassemble it and center the plunger.

[chris401]

Got it now, I thought you were talking about making a jig out of JB to guide my drill bit.

I have had to fight a few that were corroded from old brake fluid. When I bleed the brakes on this one the switch did move and cut the rear brakes off but popped back to neutral when I did the front. They move a lot smother when everything is new.

[chris401]

I did loose the brakes about 70 miles from finishing my last trip. The old steel line must have busted when I stopped for gas. I didn't know it until I was 40 miles from Roswell. With new trailer brakes and a manual transmission it wasn't a big deal. Gave me an excuse to dust off the new brake system collecting dust since 2018.

[HarleyJack17]

Sounds like you got it figured out but just to clarify, there is no spring in it. It is only pressure that moves the piston in there. Two seals on a piston. I just went through this on mine.
The below is a good link for info and possibly parts. My new seals seemed a tad small but hard to tell compared to 40 year old ones that were frozen. They sell a tool for holding it in center while doing brake jobs.
Another trick is if the piston gets hung up, the distribution block has to come off anyway. Grease zerks and a gun, and push it out. Bit of mess to clean but works great. ONLY way mine would come out. Tried every trick in the book.  Pricey to replace so I did not want to mess it up.  Something so simple can be such a pain sometimes. Irony, my sons 1984 C10, just did the brakes, same issue! Have to tear it all apart. But being a Chevy parts will be prevalent but was surprised to see a Disc/Drum setup using the same type of part. Thought that all ended with Ford in the 70's. Learn something new every day.


https://www.musclecarresearch.com/

Look around on their site. GOOD info, resources, and great customer service.

[chris401]

I was talking about the springs inside the master cylinder. I thought about tapping the MC for the 65 type brake light switch. For simplicity sake I just went 67+ all the way. I bought the pre-bent 67 F-250 brake lines from Inline Tube. When looking for a new or rebuilt valve it looked like all of the car and truck Ford's from 67 and up were the same with only a different mounting bracket. The headache you described is why I didn't buy the valve from a wrecking yard. I had been through that a couple of times myself and didn't want one that was possibly scared up from old gritty brake fluid.

Jack, do you have a preference between Muscle Car Research parts and Scott Drake?
Thank's

[Falcon67]

Got it now, I thought you were talking about making a jig out of JB to guide my drill bit.

I have had to fight a few that were corroded from old brake fluid. When I bleed the brakes on this one the switch did move and cut the rear brakes off but popped back to neutral when I did the front. They move a lot smother when everything is new.

Sorry I wasn't clear there.  But I did manage to find an image on my web site - you can just see the "tool" behind one of the lines.

[HarleyJack17]

No preference. MCR had what I needed.....or at least close. Will know shortly when I get around to bleeding the entire system. Like I said, seals looked a little small but not like I had good parts to go buy after torching, atf, T19, basically anything I could try to free up the distribution block piston. Went together tight, and seems fine.  Making all new lines and my radiator cleaning etc. set me back a bit but should get back to it this weekend.  All I have got from Scott D is parts but good service there too. As far as MCR, prices are good, and service is fantastic. Went back and forth a few times with questions and the man there gave me the tips on rebuilding etc. Put it this way, in today's world, that type of customer service is very uncommon.

I wish someone could answer the riddle on why you can not get pre-bent lines for a 1973-1977 F250 4x4. I am all ears. Every truck but that particular model.  I even bought a fancy Jegs flaring tool to do the job. Will say that was money well spent vs. the old style flare tools. Probably a wash cost wise if I could have found pre-bents but now I have a tool that will do my trans lines, and fuel etc. if I need it again.

[chris401]

Got it now, I thought you were talking about making a jig out of JB to guide my drill bit.

I have had to fight a few that were corroded from old brake fluid. When I bleed the brakes on this one the switch did move and cut the rear brakes off but popped back to neutral when I did the front. They move a lot smother when everything is new.

Sorry I wasn't clear there.  But I did manage to find an image on my web site - you can just see the "tool" behind one of the lines.

Thank's Chris, can't say for sure if I had ever seen or used one. The downside to that is keeping the valve in place you don't know if it is working. I would rather know the thing is working right.

EDIT: If the valve is in good shape it does separate the system from bleeding out the working half. If I had opened my box back home I would have seen it was likely plastic with no o-ring. That would answer the question if fluid is supposed to be behind it.