Brake fluid reservoir corroding

Hashim · 14th October 2012, 01:36

My Yamaha Gladiator which is almost 5 years old now is having a strange problem of corroding brake fluid reservoir. Bike has always been kept in garage and never exposed to bad weather.

Some pictures

Brake fluid reservoir corroding-img_0850.jpg

Brake fluid reservoir corroding-img_0851.jpg

The white stuff between the tank and its cover is engine gasket maker which I used because the tank edges were no more smooth now due to corrosion.

Brake fluid reservoir corroding-img_0852.jpg

I noticed this issue a year back and thought it was due to bad oil and so completely drained the old oil (which was the same oil which came with bike as it was never changed) and put new DOT3 oil. But today I noticed that its spreading like a disease and reached the two screws as well.

What is corroding this tank? I also noticed brakes fading today that lasted for some period and brakes were fine again itself.

Ripper · 14th October 2012, 11:46

This is absolutely Normal. I have this same issue with My pulsar. The only way out here is changing the screws to Stainless steel ones.

After every top up you need to clean the sides of the reservoir as brake oil is very corrosive and tends to burn the paint work. For the brakes fading Checked the brake kit on the reservoir end. A competent mech would help you with this.

Do a DIY paint job on the reservoir with Bosny spray paints, will make it look clean.

Hashim · 15th October 2012, 01:23

Thanks, I also noticed some screeching sound today which is coming on braking. Looks like the bike needs a visit to service centre.

I didn't knew brake oil was so bad for paint, I'll be careful with it now.

ArizonaJim · 15th October 2012, 03:01

Brake fluid by itself is not corrosive but it will dissolve paint rapidly.

If the paint is damaged the paint (or lack of it) cannot protect the metal under it from corrosion.

Even though you say your bike was protected from the elements, I suspect you washed your bike occasionally? If so, that could explain your corroded aluminum parts and rusty screws.

The stainless steel screws mentioned by Ripper will stop the corrosion or another solution to the problem is to clean the rust from the screws and then coat them with the special brake system grease that can be bought at some auto supply stores.

Brake Fluid is not an oil per se and it can be heated up to a very high temperature.
For instance, DOT 3 fluid won't boil until it is heated to 205* C and DOT 4 fluid must be heated to 230*C before it will boil.

This makes it great for use where the heat from the friction during braking heats up the metal disk and brake pads (which transfer their heat to the hydraulic brake cylinder).

Because it is not an oil, it have a bad tendency to absorb moisture right out of the air.
This water will disperse thru the fluid but it does not really combine chemically with it.
The water in the contaminated fluid will cause any metal part in the brake system like the master cylinder or the wheel cylinder and pistons to corrode and can lead to failure of the parts.
Also, if water is in the fluid, it can boil at its normal 100*C temperature and if this happens, the steam will compress just like any other gas making the brake feel spongy.

Because of the tendency to become polluted from water many companies recommend changing the brake fluid at least once a year.

As for the screeching sound, it sounds like the brake pads may be worn out.

You could inspect the pads by examining them with the help of a good flash light (torch). If the pad material that is bonded to the steel backing plate is less than 2.5mm thick, replace them.
If it is greater than 2.5mm you could use some sandpaper to sand both sides of the brake disk to create grooves that run in a direction from the axle outward.
These scratches will remove any 'glazing' that may be present on the pads while your riding.

Because brake pads are fairly inexpensive and because your life depends on them it would probably be a good idea to change them.
If you feel at all uncomfortable with your abilities to work on a brake system, take the bike to a shop with a mechanic who really knows what he's doing and have him make the repairs.

Magnaspectre · 15th October 2012, 20:49

As mentioned by ArizonaJim, the brake fluid eats through paints. Care must be taken when filling up the brake fluid reservoir that no fluid is spilt out.

Also, to prevent rust on the screws, applying anti-sieze compound on the threads before screwing them in can help.

Hashim · 15th October 2012, 21:23

Thanks everyone, today I went to service centre and the mechanic removed air from the brake pipe and added some more oil in tank as it was quite low. He also sanded not the pads but disc itself which rectified the slight wheel jamming. He said pads are fine and do not need replacement. Everything looks fine now.

Regarding the bad paint they also said its due to brake oil and it can be repainted.

14th October 2012, 01:36	#1
Hashim BHPian Join Date: Oct 2008 Location: Aligarh Posts: 449 Thanked: 49 Times View My Garage	Brake fluid reservoir corroding My Yamaha Gladiator which is almost 5 years old now is having a strange problem of corroding brake fluid reservoir. Bike has always been kept in garage and never exposed to bad weather. Some pictures The white stuff between the tank and its cover is engine gasket maker which I used because the tank edges were no more smooth now due to corrosion. I noticed this issue a year back and thought it was due to bad oil and so completely drained the old oil (which was the same oil which came with bike as it was never changed) and put new DOT3 oil. But today I noticed that its spreading like a disease and reached the two screws as well. What is corroding this tank? I also noticed brakes fading today that lasted for some period and brakes were fine again itself.
	() Thanks

14th October 2012, 11:46	#2
Ripper BHPian Join Date: Jul 2007 Location: Mumbai Posts: 262 Thanked: 38 Times View My Garage	Re: Brake fluid reservoir corroding This is absolutely Normal. I have this same issue with My pulsar. The only way out here is changing the screws to Stainless steel ones. After every top up you need to clean the sides of the reservoir as brake oil is very corrosive and tends to burn the paint work. For the brakes fading Checked the brake kit on the reservoir end. A competent mech would help you with this. Do a DIY paint job on the reservoir with Bosny spray paints, will make it look clean.
	(2) Thanks

15th October 2012, 01:23	#3
Hashim BHPian Join Date: Oct 2008 Location: Aligarh Posts: 449 Thanked: 49 Times View My Garage	Re: Brake fluid reservoir corroding Thanks, I also noticed some screeching sound today which is coming on braking. Looks like the bike needs a visit to service centre. I didn't knew brake oil was so bad for paint, I'll be careful with it now.
	() Thanks

15th October 2012, 03:01	#4
ArizonaJim Senior - BHPian Join Date: Aug 2011 Location: Phoenix, Ariz. Posts: 1,200 Thanked: 2,844 Times	Re: Brake fluid reservoir corroding Brake fluid by itself is not corrosive but it will dissolve paint rapidly. If the paint is damaged the paint (or lack of it) cannot protect the metal under it from corrosion. Even though you say your bike was protected from the elements, I suspect you washed your bike occasionally? If so, that could explain your corroded aluminum parts and rusty screws. The stainless steel screws mentioned by Ripper will stop the corrosion or another solution to the problem is to clean the rust from the screws and then coat them with the special brake system grease that can be bought at some auto supply stores. Brake Fluid is not an oil per se and it can be heated up to a very high temperature. For instance, DOT 3 fluid won't boil until it is heated to 205* C and DOT 4 fluid must be heated to 230C before it will boil. This makes it great for use where the heat from the friction during braking heats up the metal disk and brake pads (which transfer their heat to the hydraulic brake cylinder). Because it is not an oil, it have a bad tendency to absorb moisture right out of the air. This water will disperse thru the fluid but it does not really combine chemically with it. The water in the contaminated fluid will cause any metal part in the brake system like the master cylinder or the wheel cylinder and pistons to corrode and can lead to failure of the parts. Also, if water is in the fluid, it can boil at its normal 100C temperature and if this happens, the steam will compress just like any other gas making the brake feel spongy. Because of the tendency to become polluted from water many companies recommend changing the brake fluid at least once a year. As for the screeching sound, it sounds like the brake pads may be worn out. You could inspect the pads by examining them with the help of a good flash light (torch). If the pad material that is bonded to the steel backing plate is less than 2.5mm thick, replace them. If it is greater than 2.5mm you could use some sandpaper to sand both sides of the brake disk to create grooves that run in a direction from the axle outward. These scratches will remove any 'glazing' that may be present on the pads while your riding. Because brake pads are fairly inexpensive and because your life depends on them it would probably be a good idea to change them. If you feel at all uncomfortable with your abilities to work on a brake system, take the bike to a shop with a mechanic who really knows what he's doing and have him make the repairs.
	(2) Thanks

15th October 2012, 20:49	#5
Magnaspectre BHPian Join Date: Sep 2012 Location: Vasai Posts: 40 Thanked: 24 Times View My Garage	Re: Brake fluid reservoir corroding As mentioned by ArizonaJim, the brake fluid eats through paints. Care must be taken when filling up the brake fluid reservoir that no fluid is spilt out. Also, to prevent rust on the screws, applying anti-sieze compound on the threads before screwing them in can help.
	() Thanks

15th October 2012, 21:23	#6
Hashim BHPian Join Date: Oct 2008 Location: Aligarh Posts: 449 Thanked: 49 Times View My Garage	Re: Brake fluid reservoir corroding Thanks everyone, today I went to service centre and the mechanic removed air from the brake pipe and added some more oil in tank as it was quite low. He also sanded not the pads but disc itself which rectified the slight wheel jamming. He said pads are fine and do not need replacement. Everything looks fine now. Regarding the bad paint they also said its due to brake oil and it can be repainted.
	() Thanks