Hello again..I have 2 questions. First, any advice on how to remove primary and secondary pistons on the master cylinder? It's been sitting since the mid-80s and is a bit stubborn. Second, should I be able to depress the clutch release lever by hand? My engine is on a stand, and I have replaced the clutch drum and pressure disc. Just wanna make sure I assembled it correctly. And thanks for all the feedback about Olaf's parts web page
Tom AllenFt. Collins, CO
Re: brake master and clutch questions
Moderator: forumadmin
Re: brake master and clutch questions
On that master, squirt a bunch of PB-Blaster or such in the two brake line ports (take out the check valves) and also at the actuator end, let it soak for a bit, and squirt compressed air into the ports with a rubber tipped nozzle. If that doesn't do it, loosen them up a bit with a mallet from the actuator end, rinse and repeat.
Careful when you're pressurizing them--they can shoot out with a good deal of force.
Careful when you're pressurizing them--they can shoot out with a good deal of force.
Re: brake master and clutch questions
Get a piece of wood and smack the end down on it forcing the pistons to come out. It shouldn t damage the master as long as your not beating the heck out of it.
Sent from my iPhone
On that master, squirt a bunch of PB-Blaster or such in the two brake line ports (take out the check valves) and also at the actuator end, let it soak for a bit, and squirt compressed air into the ports with a rubber tipped nozzle. If that doesn't do it, loosen them up a bit with a mallet from the actuator end, rinse and repeat.
Careful when you're pressurizing them--they can shoot out with a good deal of force.
Sent from my iPhone
On May 12, 2019, at 12:57 AM, obleck@... [2cylinderhondas] wrote:
On that master, squirt a bunch of PB-Blaster or such in the two brake line ports (take out the check valves) and also at the actuator end, let it soak for a bit, and squirt compressed air into the ports with a rubber tipped nozzle. If that doesn't do it, loosen them up a bit with a mallet from the actuator end, rinse and repeat.
Careful when you're pressurizing them--they can shoot out with a good deal of force.
Re: brake master and clutch questions
Attachments :First, the master cylinder, power booster, wheel cylinders, calipers and proportioning valve should be sent to a reputable rebuilder without taking them apart. Caution; if you have several master cylinders note that there are 2 sizes of primary pistons and 4 sizes of secondary pistons, this is both diameter and length. So keeping the same set of pistons with the cylinder they came out of is ideal. However, if you are accomplished and have performed this repair before, see the following. Knowing the problem is the first step; Dot 3 brake fluid has solidified, turning into a crystal form which is locking the pistons in place. To remove the pistons in the Master cylinder, first remove/open all the ports, bolts fittings from the cylinder. Second, place it in clear water over night. In the morning using a wood dowel tap down on the pistons to break any crystals that have not made it back to a liquid state and place the cylinder back into the clear water for a few more hours. Three, put the bleed screws, brake light switches, cap flanges and 10mm bolts where the hard lines went in using bolts back in place, use one of the stop-bolts (at the end but only a few turns in so it is not touching the end of the piston which would hold it in the cylinder) and leave the other open. Then place the cylinder in a bag to catch the pistons when they fly out and using a nozzle attached to a air compressor hold it to the other stop-bolt hole force them out. If they don t come out the first time, try again. Stubborn pistons may need a second round of tapping and being placed in water, but they will come out. Rebuilding the master cylinder and other brake parts is not as simple as cleaning it and replacing the seals. The crystallized Dot 3 fluid will cause indentations in the original seals making them no longer hold. Using a small cylinder hone may clean up some of the corrosion but because these are aluminum castings most of the pitting is too deep requiring additional honing to maintain the needed diameter for the pistons. The Master, booster, rear wheel cylinders and proportioning valve being made of cast aluminum (as said) and damaging corrosion over time has made honing a waste of time. All of these cylinders will need to be sleeved in brass to give them a smooth surface for the new seals. Back to brake fluid and what they do; note that all fluids require changing Dot (Department of Transportation) 3, 4 and 5 have their own issues. Dot 3 and 4 will remove paint. Dot 3 and 4 are hydroscopic meaning they absorb water which also means that they requires changing every two years for Dot 3 and each year for Dot 4 as these fluids hold water becoming 50% water over that 1 or 2 year period. Dot 5 is non-hydroscopic (it doesn t attract or absorb water) it also will not damage paint and is kinder to seals reducing wear because of its superior lubrication properties. But it too has its draw backs compatibility with the rubber seals, not absorbing moisture means that water will collect at the lower points of the system and rust or corrode. So flushing the system every 4 or 5 years is needed, and unless the manufacturer states Dot 5 can t be mixed with Dot 3 and 4 fluids and bleeding must be done ULTRA SLOW so as not to create air bubbles in the system. And although Honda 600 s do not have ABS braking systems Silicone or Dot 5 can t be used in ABS systems. All of this should be taken into consideration before switching fluids. With RespectBill From: 2cylinderhondas@yahoogroups.com [mailto:2cylinderhondas@yahoogroups.com]
Sent: Sunday, May 12, 2019 5:22 AM
To: 2cylinderhondas@yahoogroups.com
Subject: Re: [2cylinderhondas] Re: brake master and clutch questions Get a piece of wood and smack the end down on it forcing the pistons to come out. It shouldn t damage the master as long as your not beating the heck out of it.Sent from my iPhone
On May 12, 2019, at 12:57 AM, obleck@... [2cylinderhondas] wrote:
Sent: Sunday, May 12, 2019 5:22 AM
To: 2cylinderhondas@yahoogroups.com
Subject: Re: [2cylinderhondas] Re: brake master and clutch questions Get a piece of wood and smack the end down on it forcing the pistons to come out. It shouldn t damage the master as long as your not beating the heck out of it.Sent from my iPhone
On May 12, 2019, at 12:57 AM, obleck@... [2cylinderhondas] wrote:
On that master, squirt a bunch of PB-Blaster or such in the two brake line ports (take out the check valves) and also at the actuator end, let it soak for a bit, and squirt compressed air into the ports with a rubber tipped nozzle. If that doesn't do it, loosen them up a bit with a mallet from the actuator end, rinse and repeat. Careful when you're pressurizing them--they can shoot out with a good deal of force.
-
Chuck Dean
- Posts: 78
- Joined: Thu Jun 30, 2016 8:56 am
Re: brake master and clutch questions
For break system rebuilds, I highly recommend WHITE POST.
Here is a link:
https://whitepost.com/brake-sleeving-rebuilding-services/
Chuck (mobile)Pleez x cuze enny tie ping or spelin air ores.
Our 1972 Honda 600 Coupe
Our 1961 Vespa 400
First, the master cylinder, power booster, wheel cylinders, calipers and proportioning valve should be sent to a reputable rebuilder without taking them apart. Caution; if you have several master cylinders note that there are 2 sizes of primary pistons and 4 sizes of secondary pistons, this is both diameter and length. So keeping the same set of pistons with the cylinder they came out of is ideal. However, if you are accomplished and have performed this repair before, see the following. Knowing the problem is the first step; Dot 3 brake fluid has solidified, turning into a crystal form which is locking the pistons in place. To remove the pistons in the Master cylinder, first remove/open all the ports, bolts fittings from the cylinder. Second, place it in clear water over night. In the morning using a wood dowel tap down on the pistons to break any crystals that have not made it back to a liquid state and place the cylinder back into the clear water for a few more hours. Three, put the bleed screws, brake light switches, cap flanges and 10mm bolts where the hard lines went in using bolts back in place, use one of the stop-bolts (at the end but only a few turns in so it is not touching the end of the piston which would hold it in the cylinder) and leave the other open. Then place the cylinder in a bag to catch the pistons when they fly out and using a nozzle attached to a air compressor hold it to the other stop-bolt hole force them out. If they don t come out the first time, try again. Stubborn pistons may need a second round of tapping and being placed in water, but they will come out. Rebuilding the master cylinder and other brake parts is not as simple as cleaning it and replacing the seals. The crystallized Dot 3 fluid will cause indentations in the original seals making them no longer hold. Using a small cylinder hone may clean up some of the corrosion but because these are aluminum castings most of the pitting is too deep requiring additional honing to maintain the needed diameter for the pistons. The Master, booster, rear wheel cylinders and proportioning valve being made of cast aluminum (as said) and damaging corrosion over time has made honing a waste of time. All of these cylinders will need to be sleeved in brass to give them a smooth surface for the new seals. Back to brake fluid and what they do; note that all fluids require changing Dot (Department of Transportation) 3, 4 and 5 have their own issues. Dot 3 and 4 will remove paint. Dot 3 and 4 are hydroscopic meaning they absorb water which also means that they requires changing every two years for Dot 3 and each year for Dot 4 as these fluids hold water becoming 50% water over that 1 or 2 year period. Dot 5 is non-hydroscopic (it doesn t attract or absorb water) it also will not damage paint and is kinder to seals reducing wear because of its superior lubrication properties. But it too has its draw backs compatibility with the rubber seals, not absorbing moisture means that water will collect at the lower points of the system and rust or corrode. So flushing the system every 4 or 5 years is needed, and unless the manufacturer states Dot 5 can t be mixed with Dot 3 and 4 fluids and bleeding must be done ULTRA SLOW so as not to create air bubbles in the system. And although Honda 600 s do not have ABS braking systems Silicone or Dot 5 can t be used in ABS systems. All of this should be taken into consideration before switching fluids. With RespectBill From: 2cylinderhondas@yahoogroups.com [2cylinderhondas@yahoogroups.com]
Sent: Sunday, May 12, 2019 5:22 AM
To: 2cylinderhondas@yahoogroups.com
Subject: Re: [2cylinderhondas] Re: brake master and clutch questions Get a piece of wood and smack the end down on it forcing the pistons to come out. It shouldn t damage the master as long as your not beating the heck out of it.Sent from my iPhone
On May 12, 2019, at 12:57 AM, obleck@... [2cylinderhondas] wrote:
On that master, squirt a bunch of PB-Blaster or such in the two brake line ports (take out the check valves) and also at the actuator end, let it soak for a bit, and squirt compressed air into the ports with a rubber tipped nozzle. If that doesn't do it, loosen them up a bit with a mallet from the actuator end, rinse and repeat. Careful when you're pressurizing them--they can shoot out with a good deal of force.
Here is a link:
https://whitepost.com/brake-sleeving-rebuilding-services/
Chuck (mobile)Pleez x cuze enny tie ping or spelin air ores.
Our 1972 Honda 600 Coupe
Our 1961 Vespa 400
On May 12, 2019, at 8:34 AM, 'Bill' billmyong@... [2cylinderhondas] wrote:
First, the master cylinder, power booster, wheel cylinders, calipers and proportioning valve should be sent to a reputable rebuilder without taking them apart. Caution; if you have several master cylinders note that there are 2 sizes of primary pistons and 4 sizes of secondary pistons, this is both diameter and length. So keeping the same set of pistons with the cylinder they came out of is ideal. However, if you are accomplished and have performed this repair before, see the following. Knowing the problem is the first step; Dot 3 brake fluid has solidified, turning into a crystal form which is locking the pistons in place. To remove the pistons in the Master cylinder, first remove/open all the ports, bolts fittings from the cylinder. Second, place it in clear water over night. In the morning using a wood dowel tap down on the pistons to break any crystals that have not made it back to a liquid state and place the cylinder back into the clear water for a few more hours. Three, put the bleed screws, brake light switches, cap flanges and 10mm bolts where the hard lines went in using bolts back in place, use one of the stop-bolts (at the end but only a few turns in so it is not touching the end of the piston which would hold it in the cylinder) and leave the other open. Then place the cylinder in a bag to catch the pistons when they fly out and using a nozzle attached to a air compressor hold it to the other stop-bolt hole force them out. If they don t come out the first time, try again. Stubborn pistons may need a second round of tapping and being placed in water, but they will come out. Rebuilding the master cylinder and other brake parts is not as simple as cleaning it and replacing the seals. The crystallized Dot 3 fluid will cause indentations in the original seals making them no longer hold. Using a small cylinder hone may clean up some of the corrosion but because these are aluminum castings most of the pitting is too deep requiring additional honing to maintain the needed diameter for the pistons. The Master, booster, rear wheel cylinders and proportioning valve being made of cast aluminum (as said) and damaging corrosion over time has made honing a waste of time. All of these cylinders will need to be sleeved in brass to give them a smooth surface for the new seals. Back to brake fluid and what they do; note that all fluids require changing Dot (Department of Transportation) 3, 4 and 5 have their own issues. Dot 3 and 4 will remove paint. Dot 3 and 4 are hydroscopic meaning they absorb water which also means that they requires changing every two years for Dot 3 and each year for Dot 4 as these fluids hold water becoming 50% water over that 1 or 2 year period. Dot 5 is non-hydroscopic (it doesn t attract or absorb water) it also will not damage paint and is kinder to seals reducing wear because of its superior lubrication properties. But it too has its draw backs compatibility with the rubber seals, not absorbing moisture means that water will collect at the lower points of the system and rust or corrode. So flushing the system every 4 or 5 years is needed, and unless the manufacturer states Dot 5 can t be mixed with Dot 3 and 4 fluids and bleeding must be done ULTRA SLOW so as not to create air bubbles in the system. And although Honda 600 s do not have ABS braking systems Silicone or Dot 5 can t be used in ABS systems. All of this should be taken into consideration before switching fluids. With RespectBill From: 2cylinderhondas@yahoogroups.com [2cylinderhondas@yahoogroups.com]
Sent: Sunday, May 12, 2019 5:22 AM
To: 2cylinderhondas@yahoogroups.com
Subject: Re: [2cylinderhondas] Re: brake master and clutch questions Get a piece of wood and smack the end down on it forcing the pistons to come out. It shouldn t damage the master as long as your not beating the heck out of it.Sent from my iPhone
On May 12, 2019, at 12:57 AM, obleck@... [2cylinderhondas] wrote:
On that master, squirt a bunch of PB-Blaster or such in the two brake line ports (take out the check valves) and also at the actuator end, let it soak for a bit, and squirt compressed air into the ports with a rubber tipped nozzle. If that doesn't do it, loosen them up a bit with a mallet from the actuator end, rinse and repeat. Careful when you're pressurizing them--they can shoot out with a good deal of force.