Advice Please. Brake Fluid Reservoir Corrosion

While my front brake caliper is away being refurbed, I'm checking out the master cylinder and reservoir. As you see from the picture below the reservoir is corroded:



The piston bore looks fine.

I have two questions:

1. Can I get rid of that corrosion myself without the use of any special equipment?

2. If I can then is it OK to clean up the whole master cylinder and reservoir with brake and clutch cleaner?....will it leave residue which may contaminate the new brake fluid?

I'm trying not to send the whole thing away for refurb simply on the grounds of cost.

Thanks

That's the pits. If you had good brake pressure before than master is most likely fine.  Don't spray any brake clean in there eats rubber seals.  Pick at large chunks and remove them the pitting is there forever.   Intake fluid hole has a little cover yours is broken off from what I see the only reason it's there is to stop fluid from shooting up when bleeding brakes.
Protector 45512-MA6-006 don't know how it's attached in master cylinder but it's there.

If your rebuilding all internal parts than blast away.

Part # 11

Not to differ with Mech1’s advice —he’s done more brake work than I ever have, but there are any number of YouTube motorcycle brake videos and Google links out there offering advice. Many of them say to clean the master cylinder with a brake cleaner spray which is compatible with rubber. Think rubber seals. Then clean up using brake fluid.

Don't know exactly what you consider special(especial) equipment, but been a retired aviation tech., aluminun(aluminiun for Brits) corrosion can only be removed by chemical(acids) or mechanical means(wire brush), both processes could be detrimental for the rubber parts or sight glass, any high flash brake cleaner may attack those parts also, sorry. Degreaser like simple green and a plastic toothbrush, followed by a generous water flush may be best option, then flushing out with regular rubbing alcohol to draw out moisture and let air dry for a while, you can rectify of sorts the cap mating surface with a fine flat file or fine grade sandpaper on a flat surface.

The reason we should change/flush fluid regular to avoid this, is a whole other topic, Good luck.

I think that brake fluid attracts moisture. To prevent rusting, you flush the fluid according to the manufacturers schedule. And never use brake fluid from an used source. Get new DOT4 fluid. My 2¢. Good luck.

Thanks all. I have the intake hole cover, it's a sprung fit which 'clips' into the crater next to the intake hole. It comes out quite easily and simply push-fits back in again.

BTW, I thought that all brake cleaner was kind to the rubber seals. I sometimes saturate the calipers with the spray stuff just to give them a general clean up from brake dust and road crap. Ooooops!

The only videos I could find on the web show the cleaning of mainly 'gunky' reservoirs rather than 'corroded' ones but I'll keep looking. I suppose my first attempt should be toothbrush/wirebrush and some sort of agent. My main concern is getting rid of the rust. I realise that the pitting is there for good.

zrx212, could you direct me to the type of Simple Green degreaser I might use? I've checked out their UK website: www.simplegreen.co.uk but there's quite a selection. Thanks.

Well, I've tried to clean it up using a rotary wire brush but the pitting is really bad. I'm not sure if it's useable. I'm so fed up that I've had to open a beer 4pm! However, Manchester United (1st in the Premiership), are about to play Liverpool (4th), in the FA Cup. Strange coincidence.

Anyhow here's another quick question....I'm thinking maybe I could get one (master cylinder) from eBay, but, does anyone know whether Honda kindly made the master cylinder 'compatible' throughout the years and different models, or are they 'year' and 'model' specific?

Hi, just checked few on EBay to choose from.

I can't see one specific to my 2001 model SW. Knowing Honda as I do, there may be differences between years and models....mmmmm

Loosemarbles wrote:

I can't see one specific to my 2001 model SW. Knowing Honda as I do, there may be differences between years and models....mmmmm

How about going by part #? Is it the same for other years? Are the caliper part #’s the same for other years (notwithstanding ABS)... brake pads? Seems to me that if the calipers are the same throughout the model years then the master cylinder would function perfectly well even if the part # differed. My 2¢

PSA, most aerosol/spray can brake cleaners are safe for calipers and seals, they also evaporate quickly, so they don't have a chance to soak into parts. Not really designed for use in master cylinders, but brake fluid is very wicked stuff and lives there!!.
I usually pick up simple green at BBPS(big box parts stores) in pump spray bottle.
Simple Green is a slightly caustic/acid based degreaser, it's good for cleaning bare aluminum and removing light corrosion, but should not be allowed to dry on any surface and rinsed asap.
IMO if there is no damage in actual pressure piston bore, you might be ok, just make sure also that sealing edge for cap + seal are in good condition, coating this area with caliper assembly lube or thick grease will keep moisture away. I can take a look at masters compatibility in Ron Ayers, but only applies to US models ??
Having just purchased my SW with 11k miles/8yrs old and after reading this thread, I did a full brake fluid flush/check/etc. today, in general all good, some minor corrosion in seal area, easily cleaned with white scotch brite and applied grease.
Most brake fluids are hygroscopic, simply put they suck moisture out of air, no brake system is 100 percent sealed.

Thanks again guys. I'll check the part number with a Honda parts supplier in Norfolk, (no, not Virginia). I'm now in two minds about getting it overhauled but it may be too far gone. I want to see it shiny clean in there before I introduce brake fluid.

As for the ones on eBay, I want to see inside the reservoir before I buy. Either way I'll give it my best shot before I concede!

You can always rely on me to make crisis out of drama! Life's for learning...

I checked on Ron Ayers https://www.ronayers.com/oemparts/a/hon/5053f255f870021c54be6a16/front-brake-master-cylinder-fsc60002-d03-05 and all years are same P/N 45510-MCT-006 = $116.10. I know is a US website, just for reference. To be honest I would not pay 50-75% of new cost for and unknown condition brake master on ebay, etc., if at minimun you have to install a new seal kit is aprox $35 for parts, not worth the gamble !!.

You(or someone) can bead/sand blast area, just need to remove rubber parts, protect sightglass, etc. with aluminum tape or suitable plastic tape, will need detail cleaning and maybe a re-paint, just an idea, Good luck !!

I assumed that I would have to buy the completed assembly from new costing megabucks but this looks encouraging. Thanks.

I've just checked with David Silver Spares UK and they want nearly £200 for the same 'genuine Honda' part. The only OEM one I can find is also £200.

I'll contact Ron Ayers, it might be cheaper to buy one from there and have it shipped over at half the cost of UK. The game is on....

Well, I've thrown the towel in and ordered a new Honda part from David Silver. As mentioned above, the cost of refurb etc doesn't really add up.

BTW, I was going to order a new 'protector', part number: 45512-MA6-006 (have a quick look in the parts catalogue)...it costs £27.00 + VAT....for a tiny piece of tin with a couple of holes in it.

I think I'll clean up the old one.....(£27.00, really?)

Sometimes throwing in the towel is your best move, new is new, reconditioned is reconditioned, essentially you're buying peace of mind and saving time, the most important/volatile resource, spend more time enjoying life

I don't think it could be rust because all is aluminum but could certainly be old brake fluid that has been in there forever,best to flush entire system with fresh fluid,take an acid brush clean the debris and flush with new fluid. close it up and keep your finger that the corrosion did not get into the caliper which means more work and down time,Brakes are always a handy thing to have !!!

" Brakes are always a handy thing to have !!! "

Nah, they just slow you down

Personally I would simply clean up the reservoir with a small brush or use a Dremel tool or a small steel brush, rinse the reservoir with fresh brake fluid, wipe it out good and give it a good shot of compressed air for good measure. Let it dry for a day in a warm place and put it all back together. I've done that on old bikes before and never had a problem. The reservoir doesn't have any real critical clearances such as those in the pump cylinder and valve.

The actual brake cylinder is a different critter because it's important to restore the cylinder bores to a very smooth, clean surface to prevent undue wear on the piston seals.

Just to rest this topic for now, I thought i would share my experience for anybody else who might come across this dilemma.

Having costed the parts and work involved in refurbing my caliper myself, it became clear, as some mentioned above, that a professional refurb is the answer. I begrudgingly gave in to this solution.

The only snag is, that when anybody looks at my SW all they will see is this gleaming and shiny brake caliper and utter....."oh! look, it's attached to a bike".




Cost was £174.00. It included new rubbers, bleed nipples and covers. They also cleaned the pad retaining bolt and the banjo bolts. Worth considering

BTW, I'm still waiting for my new master cylinder to arrive

One hundred and forty seven of anyone’s money is a hard pill to swallow. It does looks clean & spiffy but for that kind of money at least they could’ve powder coated those pieces too.

Now they look pukka, very nice indeed.

Money well spent.

They may have mentioned powder coating when I placed the order, but in my ignorance of the stuff, I probably said no thanks. I wanted to paint them myself but quite liked the idea of them arriving home ready to fit straight onto the bike.

Thanks JamieB. Those lucky cousins of ours across the pond enjoy much lower prices on stuff...usually, the stuff I need!

I'm feeling very humble right now after my comments above. Having chased my order for my new master cylinder I am now informed that it will arrive at the end of the month...great!?

The good news is that it comes complete with all the piston bits already installed along with the cap and seals. However, it doesn't come with the banjo bolt sealing washers...huh?

Anyhow, it explains the extortionate price. I suspect I am suffering from a touch of 'exiguous rideritis'.