Mityvac MV8000

[kythri]

I decided to give one-man brake bleeding a try, so I bought this kit last week to bleed the brakes on my Expedition.

Anyone else have this?

I'm trying to figure if I just read the instructions wrong, or if it's just a giant pile of ****.

Followed the instructions, hooked everything up like it suggested, and it was just ineffective as hell. Nothing would get a tight seal around the bleeder fitting, kept introducing air into the hose for the bleeder tool, so that I couldn't tell if I was good or not.

About the only useful bit in it was a chunk of hose that I used, along with my father, who I called over to assist. Once he arrived, we had the thing bled in a matter of minutes.

 

[mrpizza]

I use mine on my brakes, got them good. Trick is to take the bleeder off and put some pipe tape or some grease (not sure what kind) on the threads then try. Also, make a much larger catch bottle, the one it comes with *****.

 

[kythri]

Which bleeder are you referring to?

 

[TwoInch]

the air is being introduced because the vacuum is pulling air through the bleeder threads, the caliper bleeder threads. when you pump the brake pedal, there is no vacuum, only pressure. thats why you are seeing air during vacuum.

pull them out and put a small bit of teflon tape, or as i do, a dab of grease around the bleeder. that will stop all air, and you can bleed them just fine.

once you do this, the tool becomes much more realisticly functional. i believe the intructions even mention using teflon tape for this reason.

 

[mrpizza]

I use a mityvac as well. Hand operated.

 

[skruft]

I bled brakes (and one clutch slave cylinder) with a Mityvac a few times and had no trouble. I still use them but don't much care for the tools because I have had one or two fail after not much use. It seems to be the only one-handed vacuum pump though.

 

[kythri]

I suppose when I replace calipers the next time, I'll try the teflon tape, and give the pump another try. I didn't see that bit in the manual, and was bleeding due to replacing the ABS hydraulic pump in the engine bay, rather than replacing the calipers - wouldn't have wanted to pull the bleeder screws on this particular job.

 

[TwoInch]

I suppose when I replace calipers the next time, I'll try the teflon tape, and give the pump another try. I didn't see that bit in the manual, and was bleeding due to replacing the ABS hydraulic pump in the engine bay, rather than replacing the calipers - wouldn't have wanted to pull the bleeder screws on this particular job.

i dont generally feel like pulling the bleeders all the way out either, hence the dab of grease, works just as well.

 

[mech-tech]

Some people have problems with the collection canister not sealing...if yours in equiped with the cheapie inline one.

 

[kythri]

It does have an inline canister, but that didn't seem to be the issue.

Honestly, it seemed to be letting air in around the goofball rubber L-fitting that it supposed to slide on over the bleeder...

 

[signcrafter]

I have the actual mityvac made just for vacuum bleeding the brakes. I have the same issue with it pulling air in by the threads. The next time I use it I want to try some grease around the threads to seal them. Not sure what kind of grease since you don't want "oil" based grease to mix with the brake fluid.

 

[Tinner]

I've used the Mityvac for years. I just open the bleeder enough to get good flow, it usually won't **** air, if it does smear grease around the bleeder. I've only had to pull the bleeder and tape it a few times. You're not pulling enough vacuum to **** any significant amount of grease past the threads.

The metal body Mityvac, which is rebuildable, is a much better unit and well worth the money.

 

[Alfawrench]

Use caliper piston grease on the bleeder threads. No danger of contamination. Search through the elbow adaptors. There are usually several different sizes in the kit. If the ****** is not too large, slide the hose alone over it. Might get you a much better seal. Last drum brakes I did with my old silverline kit, it pulled so much vacuum that air leaked past the boot and piston seal. So sealing the threads and hose connection definitley works. And to echo other posts, a larger reservior makes things so much easier. The little cup in the kit isn't good enough for a pee test.