Questions & Answers
Questions: I have a 52 M38 and the Brake Master Cylinder has a steel line taped into the cap on the Master Brake Cylinder going to the Air cleaner canister (Water Forging Version)? Is this a custom modification and what is its purpose? Do I need to reconnect this way? Do you have the cap needed?
Question By: Jerry Miranda on Feb 27 2018 7:34 AM
This is for venting to prevent moisture build up. It is not truly necessary with proper maintenance.
Answer By: Willys Jeep Parts Tech on Feb 27 2018 12:19 PM
Questions: Hi, I have a 1967 CJ5 and my master cylinder looks like this item. However, the description states it is for 46 -66 model year. The master cylinder that your company says belongs on my Jeep is a dual reservoir. Can I use this cylinder on my 67 CJ5?
Question By: Greg Stein on Jan 22 2018 5:57 PM
This is the correct master cylinder for your CJ-5 as long as you have 9" brakes. Typically in '67, the CJ-5s had 10" brakes and had a dual reservoir master cylinder. So, as long as your Jeep has 9" brakes and the master cylinder is mounted under the driver seat of the vehicle, this is the correct one for your application. Thanks
Answer By: Willys Jeep Parts Tech on Jan 22 2018 10:27 AM
Questions: It worked great when first installed but the male connectors were loose and when I tried reconnecting them I accidentally touched the frame causing a spark. Now the brake light does not work. Is there an electrical component inside that maybe shorted out?
Question By: Derryl Acosta on Dec 27 2017 10:24 PM
647801 is a pressure brake light switch. I would check your connections and probably replace.
Answer By: Willys Jeep Parts Tech on Dec 29 2017 5:51 AM
Questions: This will work on the M170 as well?
Question By: Kevin on Nov 24 2017 10:37 PM
After checking into some manuals, this master cylinder will work for the M170. Thanks
Answer By: Admin on Nov 27 2017 5:43 AM
Questions: I have a 1950 M38 and am missing the long machine bolts where the master cylinder mounts to the frame. Do you sell that part?
Question By: Chris on Sep 12 2017 8:38 AM
Those are a hardware store item.
Answer By: Willys Jeep Parts Tech on Sep 12 2017 5:58 AM
Questions: I am replacing my current master cylinder with the 805223, however the end of my old cylinder is so rusted that i cannot get off the parts. I basically need the part numbers for end of the Master Cylinder where the brake fluid is pushed out.
Question By: Neil Netoskie on Mar 27 2017 5:13 PM
Here is a link to all the parts: https://www.kaiserwillys.com/diagram/cj-2a-diagrams/brake-diagrams-willys-cj-2a/brake-master-cylinder-41-71-willys-jeep/brake-master-cylinder-41-71-willys-jeep
Answer By: Willys Jeep Parts Tech on Mar 27 2017 10:20 AM
Questions: 1956 Willys pickup, My brake pedal goes to the floor and does not return. no brakes are engaged when pedal is on the floor. Return spring is hooked up and master has fluid. Thoughts?
Question By: Kyle Joseph Waletich on Sep 19 2016 5:37 PM
I would double check your free pedal travel and set it properly. You also need to see if your return spring is still there.
Answer By: Willys Jeep Parts Tech on Sep 19 2016 12:15 PM
Questions: i have a 59 willys station wagon 226 6cyl , would you know the bore size of the original master i would use to go to stock thanks
Question By: lou on Mar 5 2015 12:00 AM
This is the stock master cylinder above. It is a 1 bore I believe.
Answer By: Willys Tech on Mar 5 2015 12:00 AM
Questions: how do I confirm the serial # for my '48 CJ2A..........it has had an off body restoration
Question By: Russ on Jan 29 2015 12:00 AM
Answer By: Willys Tech on Jan 1 1970 12:00 AM
Questions: On item 805223 there were two answers on the distance between the 2 mounting holes- 3 1/2 and 3 3/8. Which is it ?
Question By: Aubrey king on Dec 28 2014 12:00 AM
It is 3-3/8 like original.
Answer By: Willys Tech on Dec 29 2014 12:00 AM
Questions: is there a dual master cylinder for my 49 Jeepster
Question By: Doug on Nov 18 2014 12:00 AM
You will want to get this part number the original one 805223.
Answer By: Willys Tech on Nov 18 2014 12:00 AM
Questions: The original break fluid calls for S.E.A. 70 r1.Can I use dot 4 or should I use dot 3?
Question By: mike on Nov 1 2014 12:00 AM
We usually use DOT 3.
Answer By: Willys Tech on Nov 3 2014 12:00 AM
Questions: Says it comes complete with boot. Does that include the internal parts? Are there any other parts that typically need to be replaced, when replacing the master cylinder?
Question By: Anonymous on Sep 23 2014 12:00 AM
Yes it comes with the boot as shown. It is a complete master cylinder. You may also want to get the fitting, outlet bolt, crush washers, and brake light switch with it as well. We sell all of them.
Answer By: Willys Tech on Sep 23 2014 12:00 AM
Questions: Will this Fit a 1964 M38A1?
Question By: Anonymous on Apr 28 2014 12:00 AM
Yes, this fits all the vehicles listed above.
Answer By: Willys Tech on Apr 29 2014 12:00 AM
Questions: Can I get just the cap for the 46-66 Jeep master cylinder?
Question By: Anonymous on Nov 11 2013 12:00 AM
Those are only available good used.
Answer By: Willys Tech on Nov 12 2013 12:00 AM
Questions: Will this fit my 1949 Willys CJ2A ID # 3j29453.
Question By: Anonymous on May 27 2013 12:00 AM
Yes as long as you have a CJ-2 with 2 clearance holes for mounting.
Answer By: Willys Tech on May 27 2013 12:00 AM
Questions: Will this work for a 58 Willys CJ5?
Question By: Joe on Jan 1 1970 12:00 AM
Yes this is the proper one for you. It fits all the vehicles listed above. Thanks!
Answer By: Willys Tech on Feb 27 2013 12:00 AM
Questions: Hi, My brake pedal goes to the floor.The cylinder is full and I bled the lines but did not get brake fluid out of the left rear bleeder. Could this be the plunger in the Master or what do you suggest?? I don't see any leaks. Thanks, John
Question By: John Polacek on Dec 12 2012 12:00 AM
Yes, it is probably a master cylinder issue. You should also check inside by your wheel cylinders on the drum side to make sure your rubber is not dry rot and leaking internally.
Answer By: Willys Tech on Dec 13 2012 12:00 AM
Questions: I have a leak at the master cylinder on my 48 Jeepester. Where could the leak be coming from and how would it be fixed?
Question By: Anonymous on Nov 25 2012 12:00 AM
If your old master cylinder is still on there then you probably have alot of corrosion. This will do the trick for you.
Answer By: Willys Tech on Nov 26 2012 12:00 AM
Questions: Will this fit a narrow wheel base 1958 Will Jeep FC-150?
Question By: Anonymous on Nov 5 2012 12:00 AM
Yes that is correct it is proper.
Answer By: Willys Tech on Nov 5 2012 12:00 AM
Questions: I have a 1947 willys jeep but i need the proportional valve to it i have the rest of the master brake cylinder but where can i find the proportional valve the old one whitch is ruined had the brake light hook ups on it to
Question By: wyatt on Oct 30 2012 12:00 AM
The part number is A557
Answer By: Willys Tech on Nov 4 2012 12:00 AM
Questions: Will this fit on a 1953 Willys aero lark?
Question By: Anonymous on Sep 20 2012 12:00 AM
Yes this is correct for the Aero. It is a direct replacement.
Answer By: Willys Tech on Sep 21 2012 12:00 AM
Questions: Does this master cylinder come with the connector for the brake lights?
Question By: Anonymous on Sep 19 2012 12:00 AM
The brake light switch is part number: 647801
Answer By: Willys Tech on Sep 19 2012 12:00 AM
Questions: Hello I have a 1964 m38a1 with a brake booster on it someone told me its rare to find brake boosters on them. Will this work with my brake booster and hook up right? Thanks Kevin
Question By: Kevin on Aug 23 2012 12:00 AM
The booster is unoriginal and aftermarket. Depending on the type of booster im sure this would work ok.
Answer By: Willys Tech on Aug 24 2012 12:00 AM
Questions: why are the holes unthreaded? do they have to be tapped before use? thanks
Question By: dan on Aug 1 2012 12:00 AM
This is how it was originally. You just run a bolt straight thru it.
Answer By: Willys Tech on Aug 2 2012 12:00 AM
Questions: Where do I find the serial number on a 48 jeep?
Question By: Bob Miller on Jun 26 2012 12:00 AM
On a CJ-2A they are on the firewall next to the oil bath air cleaner on the passenger side.
Answer By: Willys Tech on Jun 27 2012 12:00 AM
Questions: I notice when I search new master cyclinder for 43 MB the only thing you have by application is a rebuild kit? Is the 46 - 66 Cj's M38 etc. part #805223 really different and will not work or fit on the MB? Thanks
Question By: scott on Jun 20 2012 12:00 AM
The part number you want for a 1941-45 MB/GPW is: A556
Answer By: Willys Tech on Jun 20 2012 12:00 AM
Questions: Does this come with the cap to?
Question By: Jeff on May 22 2012 12:00 AM
Yes this is complete with cap.
Answer By: Willys Tech on May 23 2012 12:00 AM
Questions: I just need the cap for the master cylinder 1949 CJ3A. Can I just purchase that item?
Question By: Tom on May 11 2012 12:00 AM
We can probably get just that good used.
Answer By: Willys Tech on May 14 2012 12:00 AM
Questions: I have an early model M38A1 (DoD Sept. 1952) Is there anything special on the early A1's for the Master Cylinder??
Question By: Thomas Rock on Apr 7 2012 12:00 AM
No, this is the correct one for your vehicle.
Answer By: Willys Tech on Apr 9 2012 12:00 AM
Questions: Will this master cylinder fit my 1964 Jeep FC 170
Question By: Pete on Mar 7 2012 12:00 AM
Yes as long as you are single reservoir.
Answer By: Willys Tech on Mar 8 2012 12:00 AM
Questions: will this work on 1964 tuxedo park with 10brakes?
Question By: Anonymous on Feb 20 2012 12:00 AM
As long as you have a frame mounted single reservoir master cylinder this should be correct.
Answer By: Willys Tech on Feb 20 2012 12:00 AM
Questions: Will this unit fit on a 1967 cj5. Why are the holes unthreaded
Question By: Darrel on Feb 14 2012 12:00 AM
As long as you have 9 brakes with a single reservoir master cylinder mounted on the frame this is the correct one for you.
Answer By: Willys Tech on Feb 14 2012 12:00 AM
Questions: Is this Part No 805223 suitable for an FC170?
Question By: Vaughn Becker on Feb 7 2012 12:00 AM
Yes that is correct.
Answer By: Willys Tech on Feb 8 2012 12:00 AM
Questions: I have a 1971 M38A1, will this still fit?
Question By: Anonymous on Oct 15 2011 12:00 AM
Yes as long as you are frame mounted single reservoir with 9 brakes.
Answer By: Willys Tech on Oct 17 2011 12:00 AM
Questions: I want to put the disc brakes on a 1955 CJ3B. What master cylinder do I use and do you have or need a proportioning valve? Can I use valve from any Jeep vehicle with disc front, drum rear?
Question By: Jimmy on Aug 17 2011 12:00 AM
It is recommended to use a disc master cylinder and proportioning valve. We sell it in kits. Try part numbers: 376896 or 376897 depending on your Willys or Jeep.
Answer By: Willys Tech on Aug 18 2011 12:00 AM
Questions: how far does adjustable pushrod go into master cyl so i know how far i can adjust it?
Question By: kevin on Aug 15 2011 12:00 AM
You want 1 to 1-1/2 free pedal travel.
Answer By: Willys Tech on Aug 15 2011 12:00 AM
Questions: Is this only the tank or does it come with the insides too (piston, spring, outlet fitting, etc...)?
Question By: Anonymous on Jul 4 2011 12:00 AM
This is the complete master cylinder. The outlet bolt and fittings are separate.
Answer By: Willys Tech on Jul 5 2011 12:00 AM
Questions: WHAT IS THE CENTER MEASUREMENT FOR THE 2 MOUNTING HOLES
Question By: butch clark on May 25 2011 12:00 AM
It is approx 3 1/2 center to center just like original
Answer By: Willys Tech on May 25 2011 12:00 AM
Questions: Rebuilding an M38A1 1954. Original master cylinder is sloppy. Are kits dependable or should I replace?
Question By: John on Feb 8 2011 12:00 AM
The master cylinder repair kits are a good option but the bore on your old master cylinder need to be smooth. I always try to steer people towards this new master cylinder. Its just alot easier and new.
Answer By: Willys Tech on Feb 9 2011 12:00 AM
Questions: What type brake fluid goes into a M38A1 brake system?
Question By: Billy on Jan 16 2011 12:00 AM
Answer By: Willys Tech on Jan 18 2011 12:00 AM
Questions: Is their an upgrade to the orignial master cylinder currently restoring CJ-3B?
Question By: Michael on Dec 8 2010 12:00 AM
Sure, you can also use part number: 805223-CJDUAL. However this master cylinder is great and wont give you any problems.
Answer By: Willys Tech on Dec 9 2010 12:00 AM
Questions: What is the distance between the mounting holes?
Question By: Anonymous on Nov 2 2010 12:00 AM
3 3/8 center to center
Answer By: Willys Tech on Nov 3 2010 12:00 AM
Questions: I have a 1950 CJV-35. They only made 1000 of them and some of the parts are from a 3a and some from a 2a. I wanted to rebuild or replace the brakes do you have rebuild kits that I can use?
Question By: Scot on May 4 2016 5:09 PM
I would want to confirm the brakes you have on there currently. Please call me toll free. I am happy to help. Thanks!
Answer By: Willys Tech on May 4 2016 12:09 PM