DIY 001 First in a Series Bendix Tredel-Vac Restoration
Posted: Wed 11. Mar 2009, 09:13
First in a Series DIY001 Bendix Treadel-Vac Restoration.
Rev B added more detail unit types
Rev C added Supplier Harmon Classic Brakes
Parts and Rebuilding Service:
http://www.karpspb.com/
KARPS Power Brake
66 N. Central Avenue
Upland, CA 91786
Phone - 909.985.0800
Fax 909.985.5120
jeff@karpspb.com
Parts can be purchased at:
https://harmonclassicbrakes.com/
Harmon Classic Brakes, LLC
1094 Fieldstone Drive
Canton, Georgia 30114
Tel:
(678) 880-9299
(678) 880-9766
(818) 860-1934
Fax:
(678) 880-7732
Monday – Friday
9:00 – 5:00 EST
Rev-A Information about the counter bore. (59lincolnrag)
Rev-B New Identity information codes added / proper identification of this unit./ was Hydraulic- Reaction Type (a58pacer)
Special note: there were several types of power cylinders used. I will cover the Disc- Reaction Type. Its very simple in design and easy for the DIY guy or gal.
Bendix Power Assist Units
Bendix Treadle-Vac
Poppet-Valve Type
Lincoln 1956-1958 (L-3, L-4, L-5 and L-6)
Continental Mark II 1956-1957 (F)
Mercury 1956 (M and M-3)
Bendix Treadle-Vac
Hydraulic- Reaction Type
Edsel 1958 (M-5 and E-1)
Mercury 1957-1958 (M-5)
Bendix Treadle-Vac
Disc- Reaction Type
Edsel V-8 1959 (E-2)
Lincoln 1959-1960 (L-7 and L-8)
Bendix Power-Vac
Lincoln 1961-1964
Ford 1960-1961
Bendix Master-Vac
Mercury 1959-1961 (M, M-1, M-2 and F-2)
Thunderbird 1959-1961 (T and T-1)
Ford V-8 1959-1961 (F, F-1 and F-2)
Edsel V-8 1960 (F-1)
Bendix Hydro-Vac
Dealer add-on (booster only) for Mercury and Edsel.
Kits were also available from Bendix for nearly
any other make of car, 1949 on. ********************************************************************************************************************************************
Disc - Reaction Type
This unit is one of the most problematic parts on our cars. It also requires a regular maintenance schedule
Note that the shaft of this unit displaces the brake fluid, unlike a conventional master cylinder.
After dis-assembly the casting must be inspected. The inside counter-bore should be free of deterioration. Pitting of any kind will make this casting unusable. This is the root cause of total brake failure.
DO NOT HONE THE COUNTER BORE ….It cannot be resurfaced ! (Photo DSCN3739)
(The casting can be bored out and sleeved with a stainless steel insert.)
It is very important that the rubber packing along with the Bakelite washer and steel washer fit snug in the bore.
The rest of the Restoration is straight forward.
Picture 3734 through 3737 show the major components prepped refinished and ready for re-assembly
Alcohol is used to lubricate the rubber components for assembly.
Picture 3738 Shows the use of a 1 ¼ socket to install the check valve.
The check valve tension spring and fitting are the three items on top shown in frame 3736.
In order of assembly: valve spring, check valve, seal o-ring and valve fitting.
Picture 3739 Shows the Packing Assembly in order. The open end or the lip of seal fits into the cavity as shown. The lip is larger than the body of the seal. You can use isopropyl alcohol to lubricate the seal.
Note: The counter bore still has its factory (Green) alodine coating and is clean and free of pitting!
A little more information on the counter bore...........
The rubber packing fits into the counter bore as shown in the above illustration. The leading edge of the packing seal will go in first followed by the packing expansion bushing and then the washers, retaining ring and finally the leather seal. The counter bore must be free of scratches pitting gouges etc. on order for the rubber packing to do its job. Note that the leading edge seals against the bottom of the counter bore. You exert at least 150 -200 PSI when you step on the brake pedal. That is why the bore needs to be perfect. It really only seals in the first 1/16 of an inch in the bore …right down in the corner. If you hone the bore you will scratch the surface of the casting disturbing the green anodizing on the casting and allow brake fluid to seep past eventually allowing brake fluid to fill the booster and cause a soft pedal. The green anodizing seals the casting from the corrosion forces of the brake fluid. So if you’re loosing fluid and there are no leaks ….. Look again!
When you pull the unit for service it will be full of fluid. Not to mention the vacuum reserve tank will fill up as well. Believe me it holds a lot of fluid. You will be filling all the time….With no visible leaks. This running low on fluid is the number one reason for failure. The casting condition is critical. However; It can be sleeved and re-anodized, but with caution.
Additionally, the inner portion of the packing seal rubs or seals against the plunger (shaft) it too must be free of nicks, scratches etc. If it is worn scratched or nicked it mist be replaced.
Assemble over the steel plunger In order of assembly: steel cup retainer, rubber packing cup, Bakelite backing washer and steel stop washer. Then install the snap ring.
Picture 3740 Shows the Packing Assembly in the bore.
Picture 3741 Shows the steel ring at the end of the plunger that “tips” the compensating valve.
The compensating valve, sometimes called the tipper valve, is located at the bottom of the master cylinder reservoir.
A word of caution:
The tipper valve is actuated at the last fraction of an inch of the master cylinder plunger rod travel during return. It replenishes the pressure side of the brake system from the reservoir, and over a period of time, if the pressure side of the system is starved of fluid, the brakes will not work.
This allows brake fluid to enter the chamber. Refer to frame 3736 and ….
Set plunger about 1 inch inward before installing the compensator valve.
In order of assembly: insert compensating valve stem into compensating valve fitting . Then place cone shaped compensating valve spring over valve stem and assemble retaining clip.
Lubricate fitting seal o-ring with alcohol and install to master cylinder.
Picture 3743 Shows the outer plunger seal and hydraulic seal place them in order shown
Note: The replacement outer plunger seal is made with a leather insert. Refer to frame 3742. Daub your finger in Neatsfoot oil and coat the inner seal before installation. This Neats-foot oil can be purchased at any sporting goods store or an All American country hardware store you know …the old fashion store that’s got it all… The way the seal is pictured is the way it goes on. The steel plunger has a chamfer so as not to cut the seal. Wipe a small amount of Neatsfoot oil on the end of plunger and carefully place the seal over the end with a twist
Picture 3744 Insert to the master cylinder.
Picture 3745 place cork gasket to the master cylinder as shown.
Picture 3746, 3747, 3748 Install power booster cylinder to the master cylinder. Using 3 bolts as shown.
DO NOT OVER TIGHTEN BOLTS. Snug….Use a ¼ drive socket set
A word of caution:
You must change the brake fluid at least every 2 years to rid the system of moisture. Refresh the fluid and bleed the system.
PART TWO
Return to Index
Rev B added more detail unit types
Rev C added Supplier Harmon Classic Brakes
Parts and Rebuilding Service:
http://www.karpspb.com/
KARPS Power Brake
66 N. Central Avenue
Upland, CA 91786
Phone - 909.985.0800
Fax 909.985.5120
jeff@karpspb.com
Parts can be purchased at:
https://harmonclassicbrakes.com/
Harmon Classic Brakes, LLC
1094 Fieldstone Drive
Canton, Georgia 30114
Tel:
(678) 880-9299
(678) 880-9766
(818) 860-1934
Fax:
(678) 880-7732
Monday – Friday
9:00 – 5:00 EST
Rev-A Information about the counter bore. (59lincolnrag)
Rev-B New Identity information codes added / proper identification of this unit./ was Hydraulic- Reaction Type (a58pacer)
Special note: there were several types of power cylinders used. I will cover the Disc- Reaction Type. Its very simple in design and easy for the DIY guy or gal.
Bendix Power Assist Units
Bendix Treadle-Vac
Poppet-Valve Type
Lincoln 1956-1958 (L-3, L-4, L-5 and L-6)
Continental Mark II 1956-1957 (F)
Mercury 1956 (M and M-3)
Bendix Treadle-Vac
Hydraulic- Reaction Type
Edsel 1958 (M-5 and E-1)
Mercury 1957-1958 (M-5)
Bendix Treadle-Vac
Disc- Reaction Type
Edsel V-8 1959 (E-2)
Lincoln 1959-1960 (L-7 and L-8)
Bendix Power-Vac
Lincoln 1961-1964
Ford 1960-1961
Bendix Master-Vac
Mercury 1959-1961 (M, M-1, M-2 and F-2)
Thunderbird 1959-1961 (T and T-1)
Ford V-8 1959-1961 (F, F-1 and F-2)
Edsel V-8 1960 (F-1)
Bendix Hydro-Vac
Dealer add-on (booster only) for Mercury and Edsel.
Kits were also available from Bendix for nearly
any other make of car, 1949 on. ********************************************************************************************************************************************
Disc - Reaction Type
This unit is one of the most problematic parts on our cars. It also requires a regular maintenance schedule
Note that the shaft of this unit displaces the brake fluid, unlike a conventional master cylinder.
After dis-assembly the casting must be inspected. The inside counter-bore should be free of deterioration. Pitting of any kind will make this casting unusable. This is the root cause of total brake failure.
DO NOT HONE THE COUNTER BORE ….It cannot be resurfaced ! (Photo DSCN3739)
(The casting can be bored out and sleeved with a stainless steel insert.)
It is very important that the rubber packing along with the Bakelite washer and steel washer fit snug in the bore.
The rest of the Restoration is straight forward.
Picture 3734 through 3737 show the major components prepped refinished and ready for re-assembly
Alcohol is used to lubricate the rubber components for assembly.
Picture 3738 Shows the use of a 1 ¼ socket to install the check valve.
The check valve tension spring and fitting are the three items on top shown in frame 3736.
In order of assembly: valve spring, check valve, seal o-ring and valve fitting.
Picture 3739 Shows the Packing Assembly in order. The open end or the lip of seal fits into the cavity as shown. The lip is larger than the body of the seal. You can use isopropyl alcohol to lubricate the seal.
Note: The counter bore still has its factory (Green) alodine coating and is clean and free of pitting!
A little more information on the counter bore...........
The rubber packing fits into the counter bore as shown in the above illustration. The leading edge of the packing seal will go in first followed by the packing expansion bushing and then the washers, retaining ring and finally the leather seal. The counter bore must be free of scratches pitting gouges etc. on order for the rubber packing to do its job. Note that the leading edge seals against the bottom of the counter bore. You exert at least 150 -200 PSI when you step on the brake pedal. That is why the bore needs to be perfect. It really only seals in the first 1/16 of an inch in the bore …right down in the corner. If you hone the bore you will scratch the surface of the casting disturbing the green anodizing on the casting and allow brake fluid to seep past eventually allowing brake fluid to fill the booster and cause a soft pedal. The green anodizing seals the casting from the corrosion forces of the brake fluid. So if you’re loosing fluid and there are no leaks ….. Look again!
When you pull the unit for service it will be full of fluid. Not to mention the vacuum reserve tank will fill up as well. Believe me it holds a lot of fluid. You will be filling all the time….With no visible leaks. This running low on fluid is the number one reason for failure. The casting condition is critical. However; It can be sleeved and re-anodized, but with caution.
Additionally, the inner portion of the packing seal rubs or seals against the plunger (shaft) it too must be free of nicks, scratches etc. If it is worn scratched or nicked it mist be replaced.
Assemble over the steel plunger In order of assembly: steel cup retainer, rubber packing cup, Bakelite backing washer and steel stop washer. Then install the snap ring.
Picture 3740 Shows the Packing Assembly in the bore.
Picture 3741 Shows the steel ring at the end of the plunger that “tips” the compensating valve.
The compensating valve, sometimes called the tipper valve, is located at the bottom of the master cylinder reservoir.
A word of caution:
The tipper valve is actuated at the last fraction of an inch of the master cylinder plunger rod travel during return. It replenishes the pressure side of the brake system from the reservoir, and over a period of time, if the pressure side of the system is starved of fluid, the brakes will not work.
This allows brake fluid to enter the chamber. Refer to frame 3736 and ….
Set plunger about 1 inch inward before installing the compensator valve.
In order of assembly: insert compensating valve stem into compensating valve fitting . Then place cone shaped compensating valve spring over valve stem and assemble retaining clip.
Lubricate fitting seal o-ring with alcohol and install to master cylinder.
Picture 3743 Shows the outer plunger seal and hydraulic seal place them in order shown
Note: The replacement outer plunger seal is made with a leather insert. Refer to frame 3742. Daub your finger in Neatsfoot oil and coat the inner seal before installation. This Neats-foot oil can be purchased at any sporting goods store or an All American country hardware store you know …the old fashion store that’s got it all… The way the seal is pictured is the way it goes on. The steel plunger has a chamfer so as not to cut the seal. Wipe a small amount of Neatsfoot oil on the end of plunger and carefully place the seal over the end with a twist
Picture 3744 Insert to the master cylinder.
Picture 3745 place cork gasket to the master cylinder as shown.
Picture 3746, 3747, 3748 Install power booster cylinder to the master cylinder. Using 3 bolts as shown.
DO NOT OVER TIGHTEN BOLTS. Snug….Use a ¼ drive socket set
A word of caution:
You must change the brake fluid at least every 2 years to rid the system of moisture. Refresh the fluid and bleed the system.
PART TWO
Return to Index