Rebuild or Remanufactured Brake Calipers?

[E350]

carringb: Wow. Talk about turning the telescope around! So there are two opposing approaches to brake bleeding? One is pressurize the master cylinder (Motive power brake bleeder) and second is attach a hose sucking at the brake caliper bleed nipple?

Ok if I was going to do the latter, how about using the little electric Mighty vac which I think has a hose small enough to go into a glow plug hole in the rear cylinder head to suck out the oil and fuel with drips back there when doing a compression test? (I.e., to prevent subsequent hydrolocking and broken piston connecting rods.)

[carringb]

I think either approach works. This thread pretty much covers the pros and cons:
http://www.bobistheoilguy.com/forums...&Number=787908

I think any of the suction pumps would work for suctioning a cylinder. Just stab a smaller piece of vinyl hose into the regular hose when you need a smaller diameter. You could also just crank the motor briefly with the glow plug out to push the fluids out.

[oldbonesclimber]

I've had both the vacuum type and now the pressure type and I will NEVER use the vacuum type again. It it so much easier and less messy. And for the record yes that is me on the summit. I hope to do it again as soon as my second knee replacement heals. It is Eichorn Pinacle at Cathedral Peak in Yosemite. Great View. I can't even fathom what Tommy Caldwell and Kevin Jorgesen are doing. It would be like climbing up a frozen waterfall without crampons. There is just NOTHING to grip to. not even Dime edges. Congrats to them.


Paul

[boywonder]

I have a mityvac and they work pretty good......I've used it for tons of things. They come in at least two flavors: die-cast metal and injection molded plastic.

My plastic version has a broken handle and I have not used it in years. Over years of use, brake fluid ends up swelling the piston seal and the unit gets very difficult to squeeze; that's how the handle ends up snapped.

The one thing about using a mityvac is that many times you get bubbles from air leaking around the bleeder fitting, so it's easy enough to move fluid through the system, but the bubbles usually interfere with knowing when you are fully bled.

That being said, I'll probably buy another one at some point. I regularly use a syringe and some tubing to accomplish the same thing on mountain bikes and motorcycles.

[BajaSportsmobile]

Originally Posted by boywonder

The one thing about using a mityvac is that many times you get bubbles from air leaking around the bleeder fitting, so it's easy enough to move fluid through the system, but the bubbles usually interfere with knowing when you are fully bled.

I have also found this to be a problem and always finish off with a traditional bleed to be sure. It is why I prefer pressure bleeders.

[E350]

Thanks guys! Mueckster whom I really respect (he rebuilt his own 4R100 transmission for heaven's sake) over at the FTE forum has this to say:

"Moisture in the brake fluid is one of the biggest "killers" of both steel and phenolic pistons. I rebuilt many calipers, back in the early '80's as an auto mechanic, before remans were popular. The plating on the steel pistons would start to peel due to corrosion and the phenolics would swell due to absorption. This is the reason, no matter which you use, is important to flush/replace your brake fluid at least every 2 years. I still prefer the steel, over the phenolic, for the reason stated above. I'm sure the plastic compounds have improved over the years, but I'm still a bit old school when it comes to calipers.
I replaced mine with the NAPA units (steel pistons) with the brackets and hardware kits. My Ford dealer didn't have them in stock, or the rebuild parts, and I needed to get it back together ASAP. My calipers weren't sticking, but I had a torn boot on one piston and start of external piston corrosion. I replaced them as preventative maintenance while also replacing my ball joints."

I bought my current 1995 Bronco in 2005 not knowing if the brake system has ever been flushed. I know the brake system on my 2002 7.3L PSD E350 has never been flushed and that the brake system on my wife's 2000 Dodge Dakota 4x4 has never been flushed. So according to Roland, that is 20 + 13 +15 = 48 / 2 = 24 brake system flushes that I have missed. So I just ordered the Motiv pressure bleeder and the Motul DOT4 fluid on Amazon and I will let you know how things turn out.

I just got back from Napa where I ordered two new front brake hoses. While there I also looked at their reman. brake calipers. You can definitely see wear on the caliper edges where the pads slide (they have those metal inserts to cover those) so I know I will replace my hoses, but I may rebuild my calipers if they look better than the remans. BTW, the Napa guy said that Napa does not sell the caliper brackets even on their "loaded" calipers. Anyway, I am replacing my hoses and flushing the entire brake system regardless.

[boywonder]

Yes, brake fluid is quite hydrophilic....I change my brake fluid about every 50K or so miles for these same reasons.

I like to see nice yellow fluid in the master cylinder reservoir as opposed to coffee colored goo. My 5 speed honda also has a hydraulic clutch filled with DOT4 so that gets changed as well.

[E350]

I am passing on the Motul. The Motul fluid advisor only goes back to 1997 for the Ford F-150 and does not list the Bronco which was last manufactured in 1996. Although, under the Classic car button on the Motul fluid advisor states I could use the Motul RBF 600 if I had a 1968 to 1970 Mustang 351ci.

In response to my pm carringb stated:

"There's a strong possibility that some of the seals in your Bronco are not compatible with the chemistry of the Motul 600. Older rigs used more natural compounds for seals (including latex) vs the new stiff with is mostly Viton."

Thanks carringb!

So back to the drawing board for brake fluid. Do you guys have any sugestions?

[boywonder]

Originally Posted by E350

So back to the drawing board for brake fluid. Do you guys have any sugestions?

.......whatever it says on the master cylinder cap.....usually DOT3/DOT4........


I just use castrol DOT 4 from Pep Boys, etc or something similar. I've never had a need for a higher boiling point, etc the way I drive and if the stuff in the bottle meets the spec on the MS cap you should be good to go.

I look at it this way..........when was the last time (if ever) you had a brake fluid related failure? When I was racing mountain bikes years ago, we did have one brake fluid related failure when some idiot (not me, some other idiot) mixed DOT 4 and DOT 5. Although there have been times in a pinch where fellow racers used olive oil and a few other liquids for brake fluid.

There are endless discussions on another motorcycle related forum about brand(s) of motor oil, etc....and I apply the same logic for that. I do use full synthetic motor oils in everything with good reason. I could go into these reasons but this thread may get derailed.....

[JoeH]

This might seem like an odd or OCD question but has anyone painted their brake calipers?

If you're going to rebuild the stock ones wouldn't you want to throw a fresh coat of paint on them if you can clean them up sufficiently?