[ashwinprakas]

This is regarding my mom's F10D Zen, it comes with disks at front and drums at the rear.

Our usual mechanic had done some 'jugaad' to increase the brake pedal free play as a result of which I now have to floor it to panic brake, which as per his words were done so that my mom would not break traction at the front while braking which worked fine for her but she has almost given up driving and I'm the one who usually chauffers her around, and the current setup is a pain for me as I usually brake progressively late depending on feedback and since now the pedal has almost no feedback it runs the risk of me rear-ending someone.

I wish to DIY and remedy this issue, plus I wish to not go back to the mechanic in question as I hate his work ethic which though a tad better than the rest is not up to my standards.

My understanding so far is that he has adjusted actuation free play at the rear brake drum canister as front disk calipers do not have any option to adjust free-play as per my understanding. As a result of which the pedal has to go far lower than stock to apply equal pressure at all four wheels, this is just my assumption of how the system works and how he might've done it.

So experts please pour in your recommendations, I have limited experience working on car's hence detailed instructions would be of great help.

Thanks in Advance,
A.P.

[Jeroen]

Originally Posted by ashwinprakas

I have limited experience working on car's hence detailed instructions would be of great help.
.

If you have limited experience on cars, be very careful with what you are about to undertake, namely adjust the braking system.

I am not familiar with your car, but I suspect that as just about all cars it has one master brake cylinder. From the master brake cylinder four hydraulic lines will run to each brake.

There is some mechanical linkage between the brake pedal and the master brake cylinder. Usually when you want to adjust brake pedal free play it is adjusted somewhere in this mechanical linkage. Very often you might see an adjustable end where the linkage (valve rod) attaches to the master brake cylinder.

You are looking for something like this:

https://www.youtube.com/watch?v=rqyNjkWYZUs

But again, be cautious, by the sounds of it, something has been adjusted in the rear brakes only, which seems odd to me.

When working on brakes, when in doubt, don’t do it!

Jeroen

[R2D2]

Originally Posted by ashwinprakas

I wish to DIY and remedy this issue, plus I wish to not go back to the mechanic in question as I hate his work ethic which though a tad better than the rest is not up to my standards.

My understanding so far is that he has adjusted actuation free play at the rear brake drum canister as front disk calipers do not have any option to adjust free-play as per my understanding. As a result of which the pedal has to go far lower than stock to apply equal pressure at all four wheels, this is just my assumption of how the system works and how he might've done it.

The brake parts adjustable in your Zen are:

a) The brake pedal free play
b) The parking brake lever free play
c) The rear drum brake liner free play using the star wheel inside the drum assembly

He has probably adjusted a). You will need to look under the dash and at the point where the brake pedal lever contacts the master brake cylinder piston push rod. There may be an adjustment setting bolt there. It's been a long time since we had a Zen in the family (1999) so I don't remember for sure.

I have limited experience working on car's hence detailed instructions would be of great help.

DON'T do it.

I would strongly suggest you need to take your car to a MASS/dealer or an experienced technician not necessarily the one who did the 'jugaad'. Brakes must be adjusted or repaired only be persons having the required knowledge and experience. Car brakes are far more complex than 2 wheeler brakes although they operate on the same principles. In case of a partial or complete brake system failure the consequences can be severe & unpleasant.

[gkveda]

Originally Posted by ashwinprakas

I wish to DIY and remedy this issue, plus I wish to not go back to the mechanic in question as I hate his work ethic which though a tad better than the rest is not up to my standards.

Since this is the most critical part of the car + lives of the passengers inside the car + lives of the pedestrians on the road are at risk if the job is not done professionally, my suggestion would be to find another mechanic who is ethically and mechanically strong, and get the brake adjustment done. It take max of 100-200 Rs. But, it is worth it. If you do not trust the ethics of your current mechanic, then, stand in front of him while he is on the job, test the results and pay money. There is nothing that requires in this case to leave the car with mechanic and collect it 2-3 days later. This is just 30 mins job.

I am not sure if I conveyed my message in right way, without hurting anyone. But, I have tried my best to avoid it & convey my message properly.

I am sorry in advance if it has hurt you.

[scorpian]

Hello Ashwin,
From our limited discussion held i am quite sure you know what your doing and would not put anybody at risk.
I would like others have suggested you look at adjusting the free play at brake pedal,also look at the rear drum star adjusters. I hope your brake fluid is in decent shape and you have no leaks from the proportioning valve etc. If all is good you should be able to do this relatively easily. If the brake fluid hasn't been changed for long then i would suggest you bleed the system and trust me it makes a hell of a difference in the way the brake feels.
I would also suggest you check if your brake booster is holding pressure, you may pump the pedal with the engine off and it should get stiff and stay there,On starting the engine the pedal should slightly drop, in case it doesn't you may need to look in to replacement of brake booster.

[ashwinprakas]

Originally Posted by Jeroen

I am not familiar with your car, but I suspect that as just about all cars it has one master brake cylinder. From the master brake cylinder four hydraulic lines will run to each brake.

Yes, the principle is the same I believe, there's a brake booster in between and since the rear is equipped with drum brakes there's supposed to be a rotary/ratchet type self adjuster.

Which brings to mind the next question of why the auto-adjuster isn't compensating for the excess free play, if the same were to be adjusted at the rear?

Now the reason I still feel that some bullshit-mod has been done at the rear is because of the brake pedal feel, it doesn't feel springy, rather it feels as though the the pedal compresses the master cylinder piston from the moment it starts going down, I might be wrong here and this could be the normal case in the event that adjustment has been made elsewhere, say the MC linkage/valve rod as you've mentioned.

There is some mechanical linkage between the brake pedal and the master brake cylinder. Usually when you want to adjust brake pedal free play it is adjusted somewhere in this mechanical linkage. Very often you might see an adjustable end where the linkage (valve rod) attaches to the master brake cylinder.

I'm yet to spot the mechanical linkage, will need to take a better look next time I'm in there.

Originally Posted by R2D2

The brake parts adjustable in your Zen are:

a) The brake pedal free play
b) The parking brake lever free play
c) The rear drum brake liner free play using the star wheel inside the drum assembly

He has probably adjusted a). You will need to look under the dash and at the point where the brake pedal lever contacts the master brake cylinder piston push rod. There may be an adjustment setting bolt there. It's been a long time since we had a Zen in the family (1999) so I don't remember for sure.

I couldn't find the push-rod in question as I do not have an idea of how the pedal is connected to the master cylinder, will need to do some more research, though from the looks of it I'm guessing the push-rod adjuster in question is on the other side of the firewall, as I was not able to spot any linkages on the cabin side.

I would strongly suggest you need to take your car to a MASS/dealer or an experienced technician not necessarily the one who did the 'jugaad'. Brakes must be adjusted or repaired only be persons having the required knowledge and experience. Car brakes are far more complex than 2 wheeler brakes although they operate on the same principles. In case of a partial or complete brake system failure the consequences can be severe & unpleasant.

The workshop I go to is actually the best in the district, way better equipped than the MASS here. But their thoughy process is what I find compromised, they fix and tune everything to appease the typical Indian consumer. Meaning all would be fine if I restrict usage by not going on extended drives, driving passively, and not thrashing the car by any means, but unfortunately that is not how I drive or ride which surprisingly is why I am the only dissatisfied customer they have so far.

Another reason to stay away from MASS is due to the careless nature of servicemen and due to them not letting customers be present at the service bay.

I do not trust mechanics in general due to having a few experiences of negligence such as headlights wired wrong, wiring harness tampering, parts not being replaced in spite of being billed for the same, MC Cap left open, using incorrect fasteners etc.

Plus this serves as an opportunity to learn more about the machine I drive with guidance from enthusiasts who've been around the block a few times, because from experience a well educated enthusiast is way more thorough than the usual trained technician, in spite of the latter earning a living performing the same.

Originally Posted by gkveda

Since this is the most critical part of the car + lives of the passengers inside the car + lives of the pedestrians on the road are at risk if the job is not done professionally, my suggestion would be to find another mechanic who is ethically and mechanically strong, and get the brake adjustment done. It take max of 100-200 Rs. But, it is worth it. If you do not trust the ethics of your current mechanic, then, stand in front of him while he is on the job, test the results and pay money. There is nothing that requires in this case to leave the car with mechanic and collect it 2-3 days later. This is just 30 mins job.

I am not sure if I conveyed my message in right way, without hurting anyone. But, I have tried my best to avoid it & convey my message properly.

I am sorry in advance if it has hurt you.

Makes perfect sense, hence why I would not be going any further without adequate research and tools.

As of now I've not done anything evasive, just opened up things to explore and know better after which they've been reassembled as they were.

Originally Posted by scorpian

Hello Ashwin,
From our limited discussion held i am quite sure you know what your doing and would not put anybody at risk.
I would like others have suggested you look at adjusting the free play at brake pedal,also look at the rear drum star adjusters. I hope your brake fluid is in decent shape and you have no leaks from the proportioning valve etc. If all is good you should be able to do this relatively easily. If the brake fluid hasn't been changed for long then i would suggest you bleed the system and trust me it makes a hell of a difference in the way the brake feels.
I would also suggest you check if your brake booster is holding pressure, you may pump the pedal with the engine off and it should get stiff and stay there,On starting the engine the pedal should slightly drop, in case it doesn't you may need to look in to replacement of brake booster.

Once I failed to find the brake-play adjuster at the rear I decided to take off the rear wheel to see how things are on that end;



I was surprised to see a blank drum cover as I expected there to be mounting holes where bolts could be fastened or screwed in to take the cover off, guess I'd need to source some kind of drum cover puller to get the job done.



After prying the small cap concealing the hub nut off I realized that my tool kit lacks the right size box spanner socket to undo the hub nut, which means that I'd have to start sourcing box spanner sockets from 23 and above as motorcycles usually require only till 22 and that is what I have with me.



Overall I am under-equipped for the job, and since in a few thousand(>3k) kilometers I'm due for a pad change I'm guessing it would be best to let it run as it is and source the required tools and gather more information in the meanwhile.

As of now the tools which I'd require are;

1. 2 x Jack Stands.
2. Sockets from 23mm to 32mm.
3. Drum Cover Puller, if such a thing exists.
4. Copper grease.

Please do let me know if I'm missing something.

I did download the service manual for the G10B Zen from TBhp but the same doesn't provide step by step instructions, will try searching for workshop manuals for the same or even try to see if workshop manuals for the likes of international SS80 or Alto variants are available elsewhere.

Lets see how my search goes.

[gkveda]

Originally Posted by ashwinprakas

I'd need to source some kind of drum cover puller to get the job done.

No. You need to gently hammer the drum at all 4 sides and pull it with your hands. It just comes out.

But, I am becoming very pessimistic here. I somehow am feeling that after removing the calipers, you may not be able to put it back. All the best.

[Jeroen]

Originally Posted by ashwinprakas

I was surprised to see a blank drum cover as I expected there to be mounting holes where bolts could be fastened or screwed in to take the cover off, guess I'd need to source some kind of drum cover puller to get the job done.

After prying the small cap concealing the hub nut off I realized that my tool kit lacks the right size box spanner socket to undo the hub nut, which means that I'd have to start sourcing box spanner sockets from 23 and above as motorcycles usually require only till 22 and that is what I have with me.

That looks like a very wonky set up. Please don’t do anything until you get some proper axle stands.

Don’t take the nut off! It holds the wheel bearing, not the drum.

The drum cover should come off just like this, it just slides over the four studs holding the wheel. But they tend to get stuck. Spray a tiny bit of penetration oil around the four studs. Wait a few minute and gently tap the drum all around the drum, with a hammer.

Have a good look at this video which shows you how its done:
It also shows the self adjuster. Yours might be somewhat different, but the basics tend to be the same

https://www.youtube.com/watch?v=Q5j3sKgNoEs

[scorpian]

The nut needs to be taken off, bearing is pressed on to the drum.Removing the nut is not going to remove or release the bearing.
To remove the drum, tap all four sides with a rubber mallet and then it should slide off.

[R2D2]

Originally Posted by ashwinprakas

Now the reason I still feel that some bullshit-mod has been done at the rear is because of the brake pedal feel, it doesn't feel springy, rather it feels as though the the pedal compresses the master cylinder piston from the moment it starts going down, I might be wrong here and this could be the normal case in the event that adjustment has been made elsewhere, say the MC linkage/valve rod as you've mentioned.

From the symptoms you describe please check the master cylinder for proper function and for any air in the braking system.

I'm yet to spot the mechanical linkage, will need to take a better look next time I'm in there. I couldn't find the push-rod in question as I do not have an idea of how the pedal is connected to the master cylinder, will need to do some more research, though from the looks of it I'm guessing the push-rod adjuster in question is on the other side of the firewall, as I was not able to spot any linkages on the cabin side.

The push rod/piston rod comes through the firewall and from the engine bay brake booster/master cylinder combination. This point where the rod contacts the pedal will be just near the brake pedal pivot i.e. where the pedal is attached to the chassis member and swings back and fort on the pivot point. Look about 5-10 cm on either side of that pivot point.

The workshop I go to is actually the best in the district, way better equipped than the MASS here. But their thoughy process is what I find compromised, they fix and tune everything to appease the typical Indian consumer. I do not trust mechanics in general due to having a few experiences of negligence such as headlights wired wrong, wiring harness tampering, parts not being replaced in spite of being billed for the same, MC Cap left open, using incorrect fasteners etc.

I share your mistrust of mechanics in general with a few exceptions as they are prone to taking short cuts. You can also take the car back to the same mechanic who did this 'adjustment' and supervise his efforts so the outcome is to your satisfaction.

Once I failed to find the brake-play adjuster at the rear I decided to take off the rear wheel to see how things are on that end;

The star adjuster can be on the brake plate (rear) on the back of the drum assembly where the hoses connect. It may be covered with a rubber bung.

I was surprised to see a blank drum cover as I expected there to be mounting holes where bolts could be fastened or screwed in to take the cover off, guess I'd need to source some kind of drum cover puller to get the job done.

That one central hub nut holds it in place. Also,if you have noticed the nut flange has been hammered into a 'notch' on the shaft to prevent it from coming loose. Normally one replaces these nuts if they are taken off. It's a safety thing but while I advise a replacement I will leave this to your discretion.

As of now the tools which I'd require are;

Other than your list please peruse the list of things I used for my car's brake and rotor replacement and select whatever you deem required.

Tools for rotor/pad replacement

[Jeroen]

Originally Posted by scorpian

The nut needs to be taken off, bearing is pressed on to the drum.Removing the nut is not going to remove or release the bearing.
To remove the drum, tap all four sides with a rubber mallet and then it should slide off.

Interesting set up!

ashwinprakas, if you do get it off, could you take some images please and share how this looks on the inside?

Thanks
Jeroen

[guddasinha]

The easiest way to check is engage your hand brake just one click at a time and check the brake pedal travel . Keep the car engine running so that the servo has vacuum to operate. You will notice that the brake pedal travel has reduced and brake seems to be better. Drive the car and check the difference If this is the case then you need to adjust the rear drum shoe by adjusting the hand brake lever cable . Also in most cars the rear brake shoes are self / auto-adjusting type. They adjust automatically when the car is moving in reverse direction and brake is applied. You can force adjustment by driving in reverse and applying hard brake few times.
This moves the shoes to higher position . You can even apply full hand brake while driving in reverse. This should be done on a safe closed road.

[nasa_hubble]

Slightly Off Topic

The jack in the picture is upside down.
Please do take care of using the tools carefuly otherwise they may create a safety hazard.

Best of luck with your D-I-Y.

[ashwinprakas]

Originally Posted by gkveda

No. You need to gently hammer the drum at all 4 sides and pull it with your hands. It just comes out.

But, I am becoming very pessimistic here. I somehow am feeling that after removing the calipers, you may not be able to put it back. All the best.

Can't they be pushed back in?

With motorcycles we just push them back in one at a time, I understand that there would be more resistance considering the size of the hardware at hand, but should I consider opting for special tools? If so please advice.

Originally Posted by Jeroen

That looks like a very wonky set up. Please don’t do anything until you get some proper axle stands.

Don’t take the nut off! It holds the wheel bearing, not the drum.

The drum cover should come off just like this, it just slides over the four studs holding the wheel. But they tend to get stuck. Spray a tiny bit of penetration oil around the four studs. Wait a few minute and gently tap the drum all around the drum, with a hammer.

Originally Posted by scorpian

The nut needs to be taken off, bearing is pressed on to the drum.Removing the nut is not going to remove or release the bearing.
To remove the drum, tap all four sides with a rubber mallet and then it should slide off.

Originally Posted by nasa_hubble

Slightly Off Topic

The jack in the picture is upside down.
Please do take care of using the tools carefuly otherwise they may create a safety hazard.

Best of luck with your D-I-Y.

The setup was way wonkier than I'd expected it to be, guess I was using the jack upside down as well.

Would anyone recommend a good brand to buy jack stands from as I'm in the process of sourcing all the tools and I see a couple of manufacturers selling them on Amazon namely;

Big Bull - Rs.1810/-
Python - Rs. 1500/-
Gallop - Rs. 1500/-

I'm not certain whether the pricing is right, cheap or inflated, so do comment on that as well.

Would need to source a rubber mallet as well, I doubt my makeshift one would survive a car.

Originally Posted by R2D2

From the symptoms you describe please check the master cylinder for proper function and for any air in the braking system.

The push rod/piston rod comes through the firewall and from the engine bay brake booster/master cylinder combination. This point where the rod contacts the pedal will be just near the brake pedal pivot i.e. where the pedal is attached to the chassis member and swings back and fort on the pivot point. Look about 5-10 cm on either side of that pivot point.

A friend who is a service technician at MGP(in another district) did mention that the systems on our cars are self bleeding and would automatically remove air bubbles trapped in the lines, for the time being I thought that might be the case with new brake systems as once I while swapping my motorcycles brake line I could not get pressure no matter what I did so I closed everything up and called it a night, next day morning after bleeding a few drops I got compression just like that, which was so strange that at the moment I even considered religion.

Will try to get a better look tomorrow and see if I could spot it. Everything is way too cramped to have a better look.

I share your mistrust of mechanics in general with a few exceptions as they are prone to taking short cuts. You can also take the car back to the same mechanic who did this 'adjustment' and supervise his efforts so the outcome is to your satisfaction.

The star adjuster can be on the brake plate (rear) on the back of the drum assembly where the hoses connect. It may be covered with a rubber bung.

That would be a few hours of my life wasted, as I seem to be getting solid information from this thread rather than the half-bottomed logic he usually gives me for messing up things. But after brake pad and fluid replacement if I'm unable to resolve the issue then I might go back, which I doubt is unlikely, as I'm also considering replacing the adjuster cylinder as the car is going to turn 10 soon and other than the cylinders being replaced once I do not recall anything else being replaced. Do recommend if anything else needs to be replaced.

That one central hub nut holds it in place. Also,if you have noticed the nut flange has been hammered into a 'notch' on the shaft to prevent it from coming loose. Normally one replaces these nuts if they are taken off. It's a safety thing but while I advise a replacement I will leave this to your discretion.

Replacement it is!

Other than your list please peruse the list of things I used for my car's brake and rotor replacement and select whatever you deem required.

I have taken note of the suggested tools and consumables, though I'm still uncertain whether I'd need clamps to push the pistons in on the front caliper, I was under the assumption that this could be done by hand, like on a motorcycle.

Originally Posted by Jeroen

Interesting set up!

ashwinprakas, if you do get it off, could you take some images please and share how this looks on the inside?

Thanks
Jeroen

Would definitely do once I source the adequate tools for the job.

Originally Posted by guddasinha

The easiest way to check is engage your hand brake just one click at a time and check the brake pedal travel . Keep the car engine running so that the servo has vacuum to operate. You will notice that the brake pedal travel has reduced and brake seems to be better. Drive the car and check the difference If this is the case then you need to adjust the rear drum shoe by adjusting the hand brake lever cable . Also in most cars the rear brake shoes are self / auto-adjusting type. They adjust automatically when the car is moving in reverse direction and brake is applied. You can force adjustment by driving in reverse and applying hard brake few times.
This moves the shoes to higher position . You can even apply full hand brake while driving in reverse. This should be done on a safe closed road.

With the motor running I did try to engage the hand brake to see if it made a difference in brake pedal travel but it did not, isn't that strange? As I expected there to be a change in the brake pedal travel as my understanding from the video Jeroen shared is that the hand brake pulley engages the brake shows from below which should in fact result in less travel for the brake cylinder, right?

I did move the car a bit in reverse and brake hard and that made no difference, will try again tomorrow in open space and report if there's any difference.

[sagarpadaki]

The price of Jack stands online is 40-50% higher than local market. I purchased a pair of jack stands of Gallop brand for 1250 Rupees incl GST. So online, that seems like the closest to market price