I have a new to me 1940 Ford Tudor hat was hot-rodded about 2004. It has an under floorboard master, disc front and drum rear - on a Fatman front end (discs) and 9" Ford rear (drum). The brakes are woefully lacking. Multiple pumps to get 'pressure' and lacking in actual braking capabilities. As I am sorting this out (maybe needs residual pressure valves, is the MC the right one, bleeding for an underfloor MC, etc), I've taken pictures of a few suspect areas. First is what should be a brake line Tee mounted on the front frame rail going to the front disc brakes. Second is what looks like an abomination of a brake line size adapter going to the rear drum brakes? See pics below.
That in-line “adapter” is actually a residual pressure valve. Looks like one of the good ones from ECI.
It looks like ECI is it - thank you. Looks like this is 1/8" in and 1/2" out per ECI manual. I have not found a 2 psi valve in the front plumbing yet - unless that is what the block in front is. Previous owner shared the car was updated in 2004 with a Fatman front end and brakes - previous work done in the 90's. Existing rear was left in tact.
Are my eyes playing tricks on me or does the Brass Block have a 1/4" line on the single line side and two 3/16" lines on the other side?
[QUOTE="Mbear2k, post: 15414015, member: 397677" Previous owner shared the car was updated in 2004 with a Fatman front end and brakes - previous work done in the 90's. Existing rear was left in tact. [/QUOTE] Sounds like the rear is stock 1940 brakes?
The rear is a 1968 9" Ford with drum brakes. I will check on the front brass block in the morning, but believe all three are 1/8". Appreciate the input and feedback.
So if they are both ECI parts, you should be confident in them. The problem is probably somewhere else.
So looks like that is a metering valve up front. From the web: Allows the rear brakes a chance to start to engage before the front brakes do Enables user a better feel and more control Does not replace the proportioning valve, but compliments it Onward with troubleshooting. I appreciate the support here. I'll share a little history as I know it. From the previous owner, The Tudor came out of Canada and had a GM 400 and T350. The PO decided to do the front end and change the engine/trans to a Ramjet 350 (lucky me) and 200R4. I understand he left the 9" rear and MC/brakes. I mention all this as I expect this was a good working system in 2004 as he took his family all over the NE (ie, it was safe). And to mention, I know what to expect from a manual braking system (effort, etc). Also - I have had this to 2 local shops to have bled and at one, install new rear drums and shoes. The issue is that (1) 2-3 pumps to get pressure/pedal, and (2) I'll call very poor performance, needing put foot through floorboard to stop (no chance of locking the brakes up). I will say, with all that pedal effort, it does (eventually) stop straight with no pulling). So with all that I just need to dive in and do it myself. I expect I will be back here with questions as I troubleshoot. I think I'll start with doing my own flush. Then test the MC (get some plugs and test the MC), then the front/back circuits one at a time. Also I need to consider for bleeding, what complications a frame mounted MC poses (if) lower than the calipers, etc.
In re reading your first post it sounds like lack of fluid delivery. We also have no idea what actual Master Cyl you have under there. It could be something as simple as a crushed line restricting delivery, or very poor home made double flair in a joint not letting fluid pass through as needed. Where a Master is mounted has nothing to do with how well things work meaning they should work just fine. My avitar has 70 Nova disc on the front and 9" Ford 10" drum brakes on the rear. The master is a stock manual 70 Nova master cyl. In 85K miles it has never had an issue stopping. Yes, it's under the floor where it should be.
After reading your last post I'd get it off the ground and have someone on the brake pedal and go around and check that all 4 tires are getting brake pressure. Years back a customer had a similar issue after changing to a double master. One end of the piston plunger had a missing cup. We had plenty fluid when bleeding, but nothing was making pressure. It was just lowing through.
Thanks. I will do that. I meant to mention also that the car sat largely un-used for about 5 years. Apparently drive only 2-3 time a year.
That brake combination should work. Maybe go back to the basics. Check that the shoes and pads are good, wheel cylinder pistons free, calipers free to float. Rears properly adjusted. Check if master cylinder is sized properly for the system. Master cylinder push rod adjusted correctly with a good pedal return spring. Check or maybe replace residual valves if unable to determine condition; same with master. No idea on how to check that stand alone metering valve; but there is probably a way.
Thanks for that - I do need to go back to basics. I'm assuming the whole system worked (was engineered correctly) in 2004, but that's a lot of years ago. The calipers and hoses were checked by two shops, new rear drums and shoes, adjusted, etc. But time to do it myself. From the web: To test a standalone brake metering valve, you can visually inspect its exterior for damage, then connect it to an air supply and observe the valve stem movement while applying pressure, ensuring it extends outward when the brake is applied and retracts when released; if the stem doesn't move freely or shows signs of sticking, the valve might need replacement.
I agree with Rich B. I don't see anything visually that would make me question the system components. Time to do 1 wheel at a time and check Cyl pistons for drag or sticking. Sitting can cause them to oxidize and stick inside the cast housing. Especially with Dot-3 fluid. Pull each drum one side at a time and watch the action as well as peel back the rubber boots on both ends and do a visual. I'll bet you'll find something age related.
That a generic aftermarket Corvette-style master cylinder. There are a few bore sizes, and numerous vendors. This type has outlet ports on both sides, to make it easier to fit to unusual installations. The unused ones are plugged.
Thanks for both comments. I know more about the MC than I did before! I'm assuming a 1" bore, but will assess that if needed once I check/test everything else.
Thank you! I did find my 2psi residual valve for the front brakes hidden, but present. So all looks good there. On to the basics.
IF those front calipers are 70-77 general motors calipers, can I ask the question, did any 70-77 full sized general motors motor vehicle ever leave the factory with those calipers and not run a huge 11'' brake booster / servo assisted vacummmn doodad, especially IF as they are if you like stock LARGE piston calipers, they may well have been paired with a 1 1/8th bore brake master.
is it just the camera angle or do the calipers look like they are situated to the front of the caar? i thought that stang2 spindles had the rack to the front?
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