How to Bench Bleed Master Cylinder
HTML-код
- Опубликовано: 16 май 2016
- For more tips on installing a master cylinder and other brake parts, visit Garage Gurus at fmgaragegurus.com.
Bench bleeding a master cylinder is a time-saving alternative to bleeding the master cylinder on your vehicle. In this video, Master Technician Rick Kearns of Garage Gurus demonstrates how to do a master cylinder bench bleed. With insider tips, Rick shows each step of the process. After watching this video, you'll be ready to do a bench bleed next time you replace a master cylinder. Count on Garage Gurus to help you get your vehicle repair done right.
Feel free to share this video: • How to Bench Bleed Mas...
Like us on Facebook: / garagegurus
Follow us on Instagram: / garagegurus
For informational purposes only. We are not liable for any damages resulting from your reliance on this content. 
Авто/Мото
![Sean Rii, Karyon, Sharzkii - Taungule [My Love] (Official Music Video)](http://i.ytimg.com/vi/eJoMuypbSzQ/mqdefault.jpg)
To answer everyone’s question: yes a small small amount of air will go back into the cylinder during install. This air will bleed out when you bleed your brakes. Bench bleeding a MC is actually not required at all!! It does get bled during a normal brake bleed but it will take FOREVER if you are doing a pedal bleed (as opposed to vacuum or pressure bleeding). You might as well do a good job bleeding it 95% before install hence everyone doing bench bleeds. All he is doing in the video is “pumping the pedal” by pushing the piston.
Yup
Thanks for this, I'm doing my 2016 f250 today and didn't want to miss anything.
I have a bleeder with a pump so i shoukd be good to just go to the farthest brake line and start pumping away right making sure the resevor has plenty of fluid
Thank you for telling us that it's fin for a small amount of air to get back into the MC during installation! These videos all seem to skip that step (info), which is important for first-timers like me.
The problem is pumping with the pedal won’t move the piston all the way and it will retain air.Just get a power bleeder and push it from the master cylinder.
One of the better master cylinder bench bleeding how-to videos. The key point he mentioned is the mounting angle when the master cylinder is installed in the car and how this can trap air that cannot be bled out without removing the master cylinder and bench bleeding. He mentioned being able to rock (tilt down and up) the master cylinder back and forth when bench bleeding, which releases trapped air, not an option when installed in the car.
Always bench bleed it will save a ton of bleeding time. After bench bleeding take some plastic I use 3M paint masking plastic put it over the hole put the cap on over it on top of the master. That will block the vent hole so when you remove the bench bleeding hoses the fluid doesn't run out. Then it's easy to switch out the lines you can also do this on your old master to keep it from leaking fluid all down the inner fender when removing the lines.
Good tip. Thanks, I'll do this when I swap out my MC on my 2000 XJ
Thank you for the video, I like to do things right the first time and I am defiantly getting closer.
Very helpful! Been years since I’ve done this… Thank you 👍
Thanks for this great tutorial!
great video.clear and to the point.
Good video very informative, thank you!
Good quality vid. Well demostrated & explained
Great video, many thanks.
THANK YOU SO MUCH FOR THIS VIDEO! EXACTLY WHAT I NEEDED TO HELP ME DO MINE!
Nicely done. I have done it before, but I didn't recall how I did it.
Thanks for the informative video. had this go out on my off road mud truck, never even thought about bleeding the MS. I should be able to stop now LOL. its the little things that I forget sometimes. I would have just bled it until fluid comes out of the lower fittings. Then bled the brakes at the calipers. cut corners I suppose on toys. I'd still recommend bleeding the calipers as normal for other folks. just to be safe. and as always, test the brakes throughly before going into traffic. be safe
MS???....are u referring to the Master Cylinder ?
That was a very professional explanation. Compared to all these other bozos on RUclips.
Thank you!
Yeah those bozos have millions and millions of followers and views
@@ricpla6930 Doesn't mean they are giving you good information. There's a guy with a channel just feeding his turtles in his back yard pond.
@@ricpla6930 Have you heard of the Kardashians? Millions of views and followers, dumb as a fuckin rock.
Because the small amount of air that you may get into the lines will be on the pressure side of the assembly, you will push them out in your brake piston bleeding procedure.
Excellent video!!
So how do you remove the lines without air getting back in the MS when hooking up the lines to the vehicle?
As long as you don't press on the piston it won't pull any air in..
Really helpful question. ✊
@@bethridinger421 - Thank you 😊
Does MS stand for Master Cylinder?
You need to close the bleeder screws before you remove the lines off of them.
thanks for the best professinal explanation Im about to do this on my tr6 sports car thanks again
Very helpful, thank you
This is illustrative to see out of the car but you can do this with it installed on the vehicle and use the pedal.
Very helpful video! Side note, didn’t know Eugene Levy was a mechanic 😂
This guy did that Super bowl ram commercial, so god made a farmer. Has to be him🤣
Excellent.
is it possible that the air could escape into the reservor? I have bled my brakes, unfortunately it seems I may have introduced ait into the master cylinder. My brake pedal is spongy and travels too far down. I drove it for a bit and the brake fluid warning kept coming up. I think the air pockets travelled up the brakes.
I will do another bleed. It's just a PITA to do it. The reason why the brake bleed got messed up is because the eeziblled brake bleeding kit failed the brake fluid pickup tube (a 2 piece part) split apart which meant air was being pushed into the reservoir. Didn't noticed because oil was coming out the bleed nipple.
I've been trying this on a Mazda cx7 which has a different set up... The reservoir that is on the master cylinder the fill nose is on the front of it... Is there another way to bleed this system or do I have to use the fill reservoir also to do this... Thank you for the advice
You have solid fluid now, but how will that remain once you undo these fittings and attach brake lines? where will the air introduced then go?
if the reservoir is full surely no air will be reintroduced to the master cylinder while fitting it to the car, then you could just bleed the brakes once installed .
@@closertothetruth9209 He's reffering to air entering into the lines removed at the Master Cylinder itself.
once you put the lid on it will not collect air when you loosen the fittings
@@philip6419that’s fine, it’s in the lines
im wondering if ,when you remove the tubes ,if fluid should dump out of the fittings,,Im afraid my new cylinder is missing something internally as fluid is coming out when i remove them
Question: what happens when you install the Master Cylinder back on the car and remove the fittings with the plastic tubing? Doesn’t that allow air back into the MC? Thank you in advance.
Can I bleed the master cylinder that is currently on my truck or is this done only for new master cylinders? My brake pedal feels spongy.
That was great but what the hell do you do with it after you bleed it? Do you need to somehow plug the outlets before installing it?
Thank You.
How would you do this with old master cylinder? I have a 73 trans am with a top lid
Rick my name is Jose ellin I want to thank you very very much you're the only person that I saw online saying anything about the the ride on the master cylinder that if is not space properly the brakes could be locked up I want to thank you for that because I spend almost $500 taking the car to different shops and none of them could figure that out it's only until I show you a video and I remember then on a manual car instructions when you set up the clutches to leave room for the expansion of the fluid thank you Rick you save me a lot of money
will a bad brake booster make the 4 wheel drive stop working. My pedal is tight I hear air and the 4 wheel drive is not working. Ford Expedition 08
Thank you
what if you tapped on the brake cylinder or put something next to it like an orbital grinder vibrate the bubbles out?
I did this but had trouble fitting it to the car i couldn't compress the piston enough due to the fluid to get the nuts on to the studs so i emptied it then refitted and re filled then used the brake pedal to bleed out the air
Very gud demonstrations. Cheers
My master cylinder has four port holes one for each line how would l go about bleeding m/cylinder?
God bless you
Every single one of these I've seen it's so easy but tell me how you do it with the master cylinders that have a line coming out the bottom with a rubber hose. When you're taking it out of the vehicle and you disconnect that hose there's literally fluid that pours out the bottom of it out the back of it so how do you bleed it?
so i assume after the master gets, well, primed (or bench bled) there will be a little air when I install in onto the booster/lines? if thats the case, why i not just install it dry, fill the reservoir, and then bleed all the calipers?
Youll be bleeding your brakes for days that way. Itll force all the air into the abs system and through all the lines making it a way bigger pain in the ass to get it all out. Doing it on the bench first removes the vast vast majority really easily leaving only what little gets in during install to bleed from the calipers
Great job
Got a question, is it normal for a MC to shoot new air into the fluid if it is pushed in too rapidly?
No, as long as the reservoir is full of fluid.
When you remove the fittings/plastic lines after completing the bench bleed what keeps air from coming back in the pressure chambers? What prevents air from coming back into the pressure chambers through the two outputs?. Sorry,beginners question.
With the Master Cylinder at rest, Atmospheric pressure is equal on both sides of the pistons (pressure chamber), reservoir and outlet ports. Fluid encompasses the pistons and pressures chambers. As long as the master cylinder retains this fluid no air will enter the master cylinder. Gravity will try to empty the master cylinder through the outlet ports if plugs are not installed to prevent the draining of the fluid while installing the master cylinder on the vehicle. If the master cylinder goes empty then air will now enter the piston chamber. Additional bench bleeding will be required.
Thanks.@@GarageGurus
@@GarageGurus ...So you need to have some fluid in reservoir after bench bleeding to keep the pressure chamber and pistons free of air? I've never had to change a MC but looking into it...well done explanation but don't know exactly what's next, you mentioned plugs but when the plugs are removed (you have to to install brake lines) you won't get a little air back into MC or it won't matter because it's after the pressure chamber and pistons? And there will be air in brake lines(s) anyway? So that's where bleeding your brakes comes into play...right?
@@harryberry474 I think this seems to be the case from reading, but doesn’t air only travel up in fluid? 😅
@@GMoney-B Not if you’re forcing it out toward the calipers.
Great video! What bleeding kit are you using? I'm looking for the same kit. Thanks!
THEXTON 803X UNIVERSAL MASTER CYLINDER BRAKE BLEEDER KIT
why is there a black washer with holes inside the deposit fluid port?
Can you bench bleed with the MC already installed in the car doing this where you can route the tubing back into the reservoir?
Yes
@@drumrooster I’m guessing the only difference is that you can’t rock the cylinder a little bit to get more air bubbles out? If this is the case why is it such a standard to bench bleed and not bleed the MC when bolted to the booster?
Yes, you just have someone hold the brake pedal down and open the line fittings slightly. You will see the air bubble out around the line. Keep doing that until it's fluid and no bubbles. Do one port and a time.
Do you do it differently for different kinds of cars or does this work for all cars?
I know this might be a dumb question.
Basically same for any car
after bench bleeding what's the correct way to install master cylinder into car. No One has shown a video from start to finish.
I did same as you but my new master cylinder piston kept pushing in hard??
Awesome that's helpful
How do you install the master cylinder without the oil leaking out during the process?
You shouldn't have oil in your master cylinder ,do you mean brake fluid !?
great video, one question, after you did the bench bleed, how you install the brake master without the fluid couming out of it? all cars are different, some have more space some don’t, and those cars that have limited space to work require to remove the brake fluid reservoir, how you do this without spilling the fluid out of the brake master?
this is the most important question that isn't answered...I watched the whole video and wondered what next... and yeah
Use blanks to plug the holes
@@petittrainguernsey3297 That still didn't answer the question, cuz when you remove the blanks there will still be a big mess!?
@@roushl1964
Move fast...
I attach all the brake lines first, open the bleed nipples then run clear pipes (Aquarium tube works well and is cheap) back to the master cylinder.
Then pump it gently, adding fluid as the level drops, keep pumping until no bubbles come along the lines.
You’ve created a closed circuit as long as the pipes remain submerged in brake fluid.
It’s time consuming and you can bet one of the tubes will fall off. Can do all 4 together or one at a time.
Works.
@@roushl1964 there will more than likely be the same small amount of fluid coming from the cylinder from when you loosened the brake lines. A master cylinder isn't going to leak much after being unplugged. Hence the fact that it takes the amount of force of a foot to a brake pedal, to get the fluid from the cylinder to caliper or drum. In example, it would take the same force you used to bleed the cylinder to make a mess. The master cylinder holds the fluid until it is pumped/braked. Without pressure there won't be much leakage. But it's always good to be safe and have rags or a drain pan. Given the fact if you let brake fluid sit on painted parts... It will STRIP your paint!!!
What happens when you take the fittings off? Does air get in there and does it leak?
Wondering the exact same thing and not finding a video that explains that. I got the technique down but wondering same thing you asked
Once you get the master cylinder loosely back on the brake booster, you can then pull the hoses off of each fitting and attach the brake lines. There's other videos that show the plungers, springs, and seals inside the master cylinder. The idea of the bench bleed is to fill the cylinder on the bottom with brake fluid and remove all of the air. Unless the brake pedal is depressed, there's no path for the fluid in the reservoir to enter the bottom cylinder. So the only air that can get in is around the fittings. So you're looking at a slow drip situation. Since you have to bleed the brakes at each wheel anyhow, that's where you'll get rid of any air introduced when you pulled the hose off and attached the brake line.
Thank you for video god bless you
Merhaba Bendede aynı sıkıntı var nasıl hal ettin
great video. I am doing one for the first time. The fluid is just moving back and forwards in the tubes though? What is wrong? I have copied the way you set up the tubes and the reservoir. I have a 2 port cylinder similar to the one in the vid.
I have the same problem :( fighted just about 2 days , and nothing . The fluid is moving forwards and when i relase the pedal , the fluid is moving back to the box ... The pedal is not getting hard ever
Hey, did you ever figure out what was going on??
@@grzegorzmalinowski9841 either of you guys figure out what it was?? PLZ 😭😭thanks in advance
I had this problem with mine. I had to make the tubes as short as possible so they could still reach the reservoir. I was also able to play with the way I pushed the pedal, to get the fluid to move better.
What I did on 3 new MC installs so far, was raise the car to level the MC bore. Like back it up on a hill or ramps. Then reach in and press the pedal, while leaning around watching the tubes for air. I had to use both slow and fast strokes to stir up the air to get it out, but once I got it out it was great.
Won't you pour brake fluid everywhere when you release the bleed kit, thus negating the effort of bleeding it? Or is it then bled up to the outlets? I guess the piston in the relaxed position holds the fluid in. I'd love to know.
As you can see from the video every time he pushes on the piston brake fluid travels one way through the line, you never see it coming back the other way. I believe you could do this without the lines going back into the reservoir, but you'd make a mess and waste clean fluid.
Leave the pipes on till the last moment when the cylinder is in the vehicle.
@@petittrainguernsey3297 ...What good would that do if you take those lines off at ANY time and fluid leaks out? The original question was something like won't you get air into MC after the bench bleed when you remove the hoses before installing the brake lines?
@@harryberry474 If the resevoir still has fluid, then fluid will continue to seep out of the ports, and when you connect your brake lines, into the lines. Even if some air would backfeed into the cylinder, you are still much better off using this method than starting with a dry cylinder.
I really wish he explained this in the video...
Anyone can say why my car breaks is low even though my disc pads are new?
Thank you. Is this in place of the bleed you do. When one person pressing brake pedal and the other bleeding them from under vehicle. Sorry..im new having to fix my own cars
I tried to bench bleed a 2nd hand MC.
As soon as I poured brake fluid into reservoir it started leaking out of the lines...the reservoir drained empty without me even touching the pump piston.
Is that master cylinder shot,?
Did you have clear tubes secured to the outlets, and the tubes running back into the MC as shown on this video? If you didn't have the clear tubes on those outlets, gravity will cause the fluid to trickle out of those hose outlets.
@@crocodile1313
all good.
I installed the MC onto car and got it running the day after I sent you that you tube comment.
Can this is any way be done with the master cylinder on the vehicle? Reason being is a replaced all the lines and now it seems I cannot get the brakes bled correctly.
Arnold, the quick answer is yes. We recommend gravity bleed first. Make sure the master cylinder cap or lid is off or lose during this procedure. Second, perform a pedal/pressure bleed alternating from front to rear of the brake system. A common brake bleeding sequence would be RR, LR, RF, LF. If you have any additional questions, you can always give our tech line a call and they can assist you further. The Gurus Tech Hotline number is 800-325-8886 and is available
M-Th: 8:30AM-5:30PM ET
Fri: 8:30AM-5:00PM ET
Arnold not really. Depending on how your MS is set up. Sometimes the length of travel between the booster and MS is not 100%. So you will always have a residual pocket you cant bleed attached to the booster/pedal.
I know this is a year or so old but the real answer is YES. Several ways come to mind. One way is the syringe method where a syringe with a rubber tip is filled with brake fluid and injected into the MC where the brake lines connect (disconnect lines first). Another is with a pressure kit from the cap area of the reservoir. This will also be used to bleed the entire system as well. Good luck
So can you do this with help without taking it off if you’ve installed a mc without bench bleeding it? Just use the brake pedal?
Question; what happens when you take the fittings out to install it and the brake fluid runs out?
did you ever figure this out?
No one ever answers that question
kim The fluid will keep flowing out and as long as you keep fluid in holding tank. But it want get air back in master cylinder and that's what you want is no air because once you get it hooked up to the lines it is hard to get out and you don't want it going into your ABS because sometime you need a scan tool to get it out of their. And if air dose get in lines it will hopefully just a little. But you will still need to bleed brakes to get all air out of lines them selves hope this helped.
some does get in when u connect the lines. just don't let the master cylinder run dry. keep it topped up. bleed the system and ur golden.
If you have to ask this, you probably should just take it to a mechanic..
If I am only swapping the Master Cylinder, and perform this task as smoothly as this video indicates it, will I need to also bleed at the 4 wheels ?
Of course
@@RzVids UGH I know Im just sorta...... ugh lazy about it. I will I promise
@@billythomas4527 lazy? Lmao do you want to your car to come to a stop when that light turns yellow?
@@RzVids Yeah I just pull the E-Brake
@@billythomas4527 I hear that!! Bled all 4 corners 3 times before realizing my MC was shot. Dreading having to do it again. It's a pain in the ass when you have to do it by yourself 😂
where do you purchase the metal brake fittings you inserted on to the master cylinder ? I'm looking for metal fittings, not plastic.
Hydraulic or plumbing supplies shop.
@@dunebasher1971 THEXTON 803X
The air bubbles never stopped coming out on my clutch master cylinder but it drives just fine I don't know what the heck's going on
I will bet that master cylinder is from a Ford escape... I only say that because I have the exact same MC and I can't get the air out of it for nothing that is until I came across this video. I've been trying to bleed the air out while it's on the car and my pedal is still spongy. I am going to take it off and bleed it in a vice and see what happens. thanks so much for making this video...
If you close your eyes it sounds like Eugene Levy
This is only done to make sure there is no leaks on the fittings?
Do you want the lines submerged in the brake fluid while bench bleeding?
It doesn't matter because air tend to raise above liquid. Te main point here is to remove the air from the master cylinder itself, no the reservoir
Yes, it keeps the system from drawing air when you release the stroke
I hear that! Asking the same "logical" question everyone else is -- that is being avoided -- as soon as the lines are removed, there is going to be an air pocket right there.
What works for us is... Install master cylinder, leave the lines from master slightly loose and have an assistant press brake pedal slowly down and hold it there. You will see the air bubbles come out. Tighten the lines, let up on the pedal. This works most of the time for us but we always finish with a complete brake fluid flush just to make sure all the air is out of the system.
@@justincaseauto do you depres pedal tighten up screw and then repeat a few times or is it just once?
@@JosePalacio12 Most on the time we can do it once, maybe twice depending on how much air comes out the 1st time. Usually there is just a small amount of air there anyways but do it as many times as you feel is needed. If you keep getting air at the master cylinder lines there might be other issues. This is assuming the master cylinder was bench bleed completely first.
@@justincaseauto ok got it. Thanks for the reply.
Long as you do not Press the brake before reinstalling the lines then as recommended do a all wheel bleed
CAN YOU JUST DO IT WHILE ITS INSTALLED OR THERES A TRICK TO IT THAT YOU HAVE TO DO IT ON THE BENCH?
You can do it while it’s installed, but it’s waaayy harder to get the bubbles out tho. This is best for when ur replacing the master cylinder or a brake system overhaul.
What you can try to do is with your hands, just bang the master Cylinder a few time to try and shake up the bubbles. Also bleeding the brakes helps out too. You can also suck out the old fluid from the reservoir and put new one in, then bleed. You can also pressure bleed the system. I’m sure you can find a vid out somewhere
There's no vacuum on the MC side of the booster.
What about taking the tubes off, excess fluid, etc? Finish the job before you end the video!
what could be the cause if you do this but no fluid comes out when you press it? brand new master cyl too
Wow this guy's voice sounds just like Eugene Levy.
I thought this too! After reading your comment all I thought of was “Johhhhnathaaaaan” from schitts creek.
Why doesn't anyone show how to bleed a four port master cylinder.
Brake booster
Eh? There's no brake booster in this video.
you didnt do it correctly, the cylinder has to be at an angle which is opposite end of the piston, so piston push rods is facing upwards toweards the sky, reason for this is that if its level or the fitting end is facing the sky. air will still be trapped inside of it.
We've all done good brake jobs that don't end up well. I finally bought a new master cylinder for my car after doing a brake bleeding with no good results. Bad master cylinder in a 50yo car. Spend the money for a new master cylinder. Rubber goes bad, and don't halfass it. Too much at stake.
Hi 1A Auto. You have great videos. But regarding breaking. I have a Chevrolet Trax 2014 FWD 1.7 TD. And for 1,5 years nobody has diagnosed My issue right.
There is no computer signal or error code that shows up. But My front right and rear back brakes are randomly staying pushed against the rotors whenever the brakes are used. Even it is just once.
The weird thing is, it's not all the time like that. It comes and goes randomly.
Everything from the hoses, to the brake lines to the saddle and supports, rotors and disks are changed out. The main vacuum pump has been checked and is OK.
The ABS fuse has been tested. Meaning it has been taken out to see if it's an ABS or EBCM issue. But the issue still was there. So we put back the ABS fuse. And no one got wiser :(
The vacuum membrane has not been looked at and it seems that no one here in Estonia is qualified to do that either. Not even the Chevrolet dealers mechanics at Autospirit nor Opel dealers mechanics have identified the issue correctly. They just keep changing out parts but not diagnosing the underlying issue at all. Do you have come across an issue like that? Any advice?
Take all the rotors and calipers off, no need to disconnect the caliper unless you really wanna bleed a system for no reason that day. Inspect it all for abnormal wear, inspect everything around it for wear marks or abnormalities, reinstall caliper around the rotor, check clearance of pads it should be equal to both sides, if one piston of a caliper looks more forward or recessed than the others and no other brake imput is given you know you have a problem with the caliper specifically, w everything replaced I'm more willing to believe that rushed work has led to a sloppy fit. I know I've had to redo my brakes once or twice just because I didn't align it all "properly". Also if the car is just seeming to randomly bite w heavier braking my Chevy truck(s10) does that too the wheels almost lock when everything's really cold I just chalked it up to abs fucking around with me. System can work perfectly fine and still be a POS at the end of the day.
NONE of the videos I’ve watched, explain what to do after the bleed with the tubes. which comes out 1st, tube or plastic fitting. Which one of the 2 fittings/tubes 1st…. etc. How do we not just end up with all new air after removing them…
So next time dont stop the video to make it look simple!! You learn best by watching others! How we know what you did between pausing?
You know what kills this Channel? The obvious corporate influence involved in the video production, otherwise it would be such a great RUclips channel. Just goes to show how corporations need to keep their grubby ass hands off of things sometimes
Everyone asking about air going back into the MC when removing the lines to install, just take it to a mechanic. It will be safer for everyone.
Thank you!
John 14:6
Jesus saith, I am the way, the truth, and the life. No man cometh unto the Father except by me.
Falas falas mas não dizes nada
Why anyone would not take advantage of the higher boiling point of and backwards compatibility of DOT4 when changing the master cylinder and flushing the system is beyond me...
Not every vehicle can use different brake fluids, and some vehicles require very specific brake fluid type.
Some vehicles can use either DOT 3 or DOT 4, while others have to use only one type of brake fluid, for example just DOT 3, not DOT 4.
Also some Dot 3 is suitable for most or all DOT 3 applications such as Prestone branded universal DOT 3, while other DOT 3 such as the OEM branded ones have different types of brake fluids, Dot 3 for Domestic, Dot 3 for European, Dot 3 for Asian automobiles, the formulas would have something different in them, that's why its rated for different makes of vehicles.
Have a look at the brake fluid bottle, they will have the temperature rating on the front, and even comparing DOT 4 to another DOT 4 they can have different temperature ratings, and some brake fluid are synthetic and some are non synthetic.
Check the brake fluid cap / reservoir, owners manual for the correct brake fluid type for your vehicle, and use the recommended fluid.
No need to bench
Wait a minute. Wait a minute. You did the test on the NEW master cylinder! You're supposed to test the "bad" one so we can see if our original m/c is faulty before replacing it. smh!!
The overt crack concordingly moan because algebra startlingly settle on a military chief. pushy, awesome utensil
What?
You should not push the plunger all the way in, you can damage the seals doing that. Only push it in about an inch or so. Good video otherwise.
thats only for old cylinders brah
3/4' to 1' max for the reason you stated....
Yep and also use a wood dowel to push the piston, not a screwdriver!
I believe it will only damage the seals in a used cylinder with a line developed in the bore from corrosion or wear. Otherwise on a new MC it should be ok.
Thank you