Ford Muscle Cars Tech Forum banner

1 - 20 of 25 Posts

·
Registered
Joined
·
262 Posts
Discussion Starter #1
SO ive got my ^67 on the road again after sitting for a few years. Rebiult the edelbrock carb, new freeze plugs, t-stat.
So now, its time to figure out the mc situation.
It had always felt rock hard, and always had to stay back. If i stay hard on the brakes, it willl start to grab, but forget about a emergency stop.
I had a mobile mechanic work on my honda a while ago, and he wanted to check it out. I popped the hood, and he asked if it had disk/drum. No i said its drum/drum manual. He said I have the wrong m/c. He said thats why my brakes dont work right.
So, is it because disc brakes use less pressur to work, and since it was trying to push shoes out, all these years, was I only using the rear drums?
It all sounds right. Looking at pictures online shows m/c's that are drum/drum manual, the res. tops look different. Mine looks like a disc/drum.
This weekend, Im going to get the proper m/c and see what's up.
Ive changed it before years ago, but had just replaced with what the parts store gave me.
Does this all jive with the symptoms?
 

·
Registered
Joined
·
5,337 Posts
You have a disc/drum MC on the car. It is incorrect for a drum/drum application. The disc reservoir outlet will not have a residual valve and piston size is most likely incorrect.

Can you post a photo of how it is plumbed, i.e. @ the distribution block and MC outlets? Were you able to use the original fittings or did they have to be changed (you or shop)?
 

·
Registered
Joined
·
262 Posts
Discussion Starter #3

here you go. I didnt change a thing. like I said, I just replaced it with the one schmuck's sold me. years ago. it was identical to the one i took off
 

·
Registered
Joined
·
10,315 Posts
From a technical standpoint (not originality), that MC (if the correct one for a disc/drum Fairlane as it appears to be) should work fine - except the pushrod. To use that disc MC, the pushrod would have to be custom selected or modified to work right. If it was, then although it's not the 'correct' one, your braking issue is somewhere else in the system. If it wasn't, you know what to check and change or swap-out first.

David
 

·
Registered
Joined
·
5,337 Posts
Simply buy and install the correct MC and save yourself a lot of time and trouble with offered brake theory.
 

·
Registered
Joined
·
10,315 Posts
My offer was to save him time and trouble with a simple diagnostic so he knows better what he's up against. While I fully expect him to change to the 'correct' MC, he can save a lot of time and some money doing the project in one session with more info or logical diagnostic steps, than piecemeal. I'm just trying to be more helpful by adding to yours. What are you doing?

David
 

·
Registered
Joined
·
262 Posts
Discussion Starter #8
easy!easy!:bicker:
im sure that once i get the correct drum/drum mc on there, it will be fine. I'm going to flush the entire system, too.
If not, I will start at slave cylinders. Although they were replaced a few years ago.
But yea, the correct parts is a good starting point.
I will be doing that this weekend. The mc comes with a rod, just incase the one i have is different.
 

·
Registered
Joined
·
10,315 Posts
No problem, but my point was that you can use what you have now to be diagnosing other potential issues, so you don't have to install the new MC, bleed it all, check it, and then try to find what else is wrong. If the MC pushrod has been corrected for the current MC, then you can diagnose the down-stream issues now, saving multiple trips, time, labor, repetitive bleeding, and a 99-page thread.

If the rod is not the correct length, then you can either do a quick temporary fix to the rod with a filler piece in the MC piston, then see if that's the whole issue, and if not, then be able to test for down-stream issues as above. All the same benefits as above.

This is not an exercise in theory. It is a means to avoid spending any more time or money on this part of the project than necessary, and a method of diagnostic thinking that professional mechanics and techs use to get the job done quick and right - or they lose the race and starve. That's all. I hope it's of use to you.

David
 

·
Registered
Joined
·
262 Posts
Discussion Starter #10
it is all useful to me.
Thank you both.
I'll let you know how it goes monday.
 

·
Registered
Joined
·
5,337 Posts
I'm just trying to be more helpful by adding to yours. What are you doing?

David
Trying to stay out of your sight so that the next time your medication levels get too low, I won't be the subject of another vile and menacing fist shaken in my face... :(


This is not an exercise in theory. It is a means to avoid spending any more time or money on this part of the project than necessary, and

...a method of diagnostic thinking that professional mechanics and techs use to get the job done quick and right - or they lose the race and starve.

David


If one (professional mechanic OR tech :confused: ) goes through the Chinese Fire Drill you are suggesting, they most likely will be sent home.

David,

He has already had a professional tech look at it and tell him what he needs. Regardless, the MC is going to have to be replaced. Whatever lies downstream that is defective will be defective regardless of the MC type.
 

·
Registered
Joined
·
262 Posts
Discussion Starter #12
yeah, im just starting from the top down. it isnt a daily driver right now, so its ok if it is in pieces for a few stretches between paycheck. Im sure the brake kit springs are stretched out at this point. sometimes when Ide just start it to keep it running, ide drive up n down the drive to 'get thebrakes back in', some times one of the drums would freeze up, then id nail the brakes in reverse to get the star to click a few times, then it would work as usual, then id park it.
 

·
Registered
Joined
·
262 Posts
Discussion Starter #13
got the rite mc installed. The rod that came with it was the same length as the old one, minus the rust. so I switched that out.
I bled out the whole system and adjusted the star adjusters to just a slight hiss of shoe drag. Greased up my ball joints too.
The test drive revealed a firm, but resilient pedal, so the feel improved, and it stopped straight, didnt pull, But I still think it should stop better.
My thinking is that over time while it has been sitting, and occasionally driving around the drive, rust that forms on the drums has been driven into the shoes, lengthening stopping distance.
So now, I will be getting spring kits and shoes.
The old fluid that came out was dark, but not gelled. I had a e-150 that had gelled the brake fluid in the rear. That was gross.
One question to you guys- My rear bleeder screws are 10mm, and the fronts are 7mm. Is it just because thats what the cheap taiwan slave cylinder manus. used? Threw me for a loop.
 

·
Registered
Joined
·
262 Posts
Discussion Starter #14
raining like hell out here...
so all I did was pull the car into the garage, and run a box fan under the car to dry out the drips.
Tomoroow I plan on taking all four drums off, and getting the drums turned, and get new wheel cylinders, and shoes , and spring kits.
One Q though, I have read on the spindle nut, to torque to 18-25 ft/lbs, then back off, then torque to 10 #'s.
That info is out of a 68+ torino shop manual, is that the same? I assume it is, just checkin.
Thanks.
 

·
Registered
Joined
·
5,337 Posts
One Q though, I have read on the spindle nut, to torque to 18-25 ft/lbs, then back off, then torque to 10 #'s.

That info is out of a 68+ torino shop manual, is that the same? I assume it is, just checkin.

Thanks.
Run it down to the torque spec while rotating the wheel. This forces excess grease out of the bearing(s) and seats then in the cups properly. Backing off will give correct final adjustment.
 

·
Registered
Joined
·
262 Posts
Discussion Starter #16
and thenfinger tight after the back off? I only got the front drums off tonight. just wasnt feeling it.
The springs and things looked pretty crusty on one side, but the bearings, races, and the spindle still look new.
 

·
Registered
Joined
·
5,337 Posts
and thenfinger tight after the back off? I only got the front drums off tonight. just wasnt feeling it.

The springs and things looked pretty crusty on one side, but the bearings, races, and the spindle still look new.
I am sorry, I wasn't as clear as I should have been.

I have read on the spindle nut, to torque to 18-25 ft/lbs, then back off, then torque to 10 #'s (re-torque to ten ft. lb).
Also, if you have filth under the brake assembly, suspect a bad hub seal, but you were going to replace that regardless, correct?
 

·
Registered
Joined
·
262 Posts
Discussion Starter #18
The seal looked fine, but i was gonna yank it anyways to repack my bearing.
Whats it called, hub seal? Spindle seal?
 

·
Registered
Joined
·
5,337 Posts
Front grease seal-

It is replaced as a matter of fact when performing a brake job. Nothing like fresh grease running all over your new expensive parts.
 

·
Registered
Joined
·
262 Posts
Discussion Starter #20
i yanked the rear drums today.
On one side, the self adjuster hook was unhooked, and the other side shoes looked like they were over heated. the material looked brittle and cracked, but no pieces floating around in there. On the plus side-axle seals still holding.
Got new hard wear and shoes on order. Although, I thought the rears were 2 inch shoes, i had already ordered them before pulling the drums, but I have 1and 3/4 shoes back there. But it looks like there is enuf room in the drum to take 2 inchers.Is the extra size centered? IE- 1/8 of an inch more on each side, or 1/4 more on one side? Ide like to get as much shoe in there as I can.
 
1 - 20 of 25 Posts
Top