[Trust_In_Thrust]

Dear Members,

I have a peculiar problem with my 800 .
When the brakes are cold they are good.
But after some usage i get pulsating feeling in the brake pedal.
I have changed master cylinder, brake shoes ,all four tyre, calipers , brake discs till now but the problem has not sorted out.

all wheel bearings have been checked,
the problem becomes prominent at speeds in excess of 80 Kmph.
I went to Maruti Service stations but they said they will change everything it is like hit and trial,
also i actually got all the rotating parts , hubs , discs , brake cylinders , dismantled and checked for problems on lathe machines but they had no issues at all.Also bleeding has been done around 4 times but no resolution of problem.
The problem started at least i noticed it after i got my tyres balanced one day.But i have been getting tyres balanced from same shop for past 5 years.I also tried other shops but there is no steering wobble .
Now :
1. The car stays in straight line while driving so alignment is alright.
2. There is no steering wobble so balancing is right.
3. All braces , hubs , bearings etc have been checked and are ok.

Got any ideas what can be the problem.
Regards

[humyum]

I am sure about this, while balancing you rotated the tyres and one of your tyre/rim is faulty and hence the vibration since you have checked everythign else.
Rim can be out of center or the tyre can have bubbles/tears and what not.

[16v100bhp]

Seems like you have done almost everything. It seems like a hydraulics issue to me. Brake cylinders may be the next thing I would check. But all those parts you had changed, are those MGP? if not the non OE pads are sometimes good for nothing! also.. if you have faced the disks from a lathe instead of replacing them new, there might be an issue...

[pshyamsundar]

Even I am having the same problem I feel that there is no bite in the break. It is kinda very hard. It is like pressing a stone. There is not brake feedback. I also do not know how to correct it.

[Trust_In_Thrust]

HumYum :

I have already done a complete check by using a friend's rim/tyres but problem remains.

16v100bhp :

Changed to booster type master cylinder , calipers were also changed All parts are MGP . The brake pads are Rane make since they have been working better for me in comparison to TVS/KBX type.Also the brake discs are new .The only reason i love 800 is i can torment , thrash it totally and do not bother about service issues beacuse it is so easy on pocket i can get everything replaced without any burden.

pshyamsundar :

Try getting bleeding done , also check the level of brake oil and brake pads.Also grease the caliper pins .And try to check under the dashboard firewall if the valve of master cylinder is leaking .If yes it will be oily there and only solution to this is a new master cylinder arund Rs. 600 /- or Rs 2800 /- booster type.


Well there has been a change is the nature of problem now.Instead the long up down movement of pedal i was feeling earlier it has shortened a lot but now the frequency is higher .I am still stumped . One problem in 3,12,000+ , 16 years of service and i am eating my brains out.

[sumeethaldankar]

Originally Posted by pshyamsundar

Even I am having the same problem I feel that there is no bite in the break. It is kinda very hard. It is like pressing a stone. There is not brake feedback. I also do not know how to correct it.

Hi Get your front brake pads changed and also have the rear calipers examined.

[sgiitk]

Originally Posted by sumeethaldankar

Hi Get your front brake pads changed and also have the rear calipers examined.

Are you not the other way round. Front has discs (calipers) and rear drums (shoes/pads). My own suspicion will fall on the discs being 'wobbly'. Also, check the bearings in case this leads to the wobble. I doubt that it is the rims since the problem is only with warm brakes.

[inderjeet singh]

hi dear,
u mite be having problem in the dics rotor balancing.its not wheel balancing this is the work of laith workshop (kharad).the plates should be properly faced both the side at one time.Every time u change your disc pads the rotor plate should be checked.As front check rear drums also by laith men.M running a workshop so these type of problem are very common.
hope you find the solution of your problem.
Balancing never cause pulsating problem in the brake pedal..

[sumeethaldankar]

Originally Posted by sgiitk

Are you not the other way round. Front has discs (calipers) and rear drums (shoes/pads).

Hiyes i meant the rear brake drums and front disc brake pads.Thanks for pointing out.

[Volt]

I too think its a hydraulics issue, particularly because you mentioned the pulsating. When you changed all the parts, did you change the lines/hoses? If these are old, they could be a problem. Get them checked/ changed if needed.

[Trust_In_Thrust]

Well friends after all the money down the drain the problem remained unsolved .Strangely today the problem disappeared completely as i did not notice it at all on my 500 km Delhi to Jaipur to Delhi.
I just pray it does not recur .
Thanks for all the suggestions and help.

[Trust_In_Thrust]

Well here i go again .The problem has come back.
Can anyone suggest a extremely proficient service centre , MASS , etc in/near Rohini,New Delhi who is willing to change my 800 disc with full assurance and a guarantee that i will not have the same problem again.

[HKS]

Why is sounding to be that the problem could be with the drum. When its cold braking is fine and doesn't brake well once the car is well and running, that means at higher temperature. Isn't the drum fading?

[Trust_In_Thrust]

@HKS . The problem is with the discs .Everytime (3 times) i had it machined for tureness. Few 100 kms it will be fine and then it will warp again.
Today again i ended up spending 2000 Rs for new hubs , new discs , all MGP .I also went to the temple for praying the problem doesnot resurfaces.All work was done at MASS .

[HKS]

Ahhh.

Wheel. Wheel is the issue that everytime your disc has problems. God won't help you. You have to help yourself in this case.