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wsrobert
07-20-2007, 11:15 PM
I recently had a brake line come loose and all the fluid drained out. I've repaired the line, but how do you bleed the air out of the system? I know there's got to be a simple way, but I'm drawing a blank.

Doug G
07-20-2007, 11:39 PM
Strap a friend up to the axle and have them work the bleeder while you drive around

1boarder
07-21-2007, 10:58 AM
I'm sure it is an easier way, but I did it by backing up the truck to push in the actuator and then getting out and bleading the pressure off of the brake. Close the bleed and then pull forward and reverse again over and over. There is a slight hill in my driveway that kept the actuator compressed. You could also put a board behind the trailer tire and back the trailer up to compress the actuator. Start with the brake that has the longest line to it and make sure to keep the resivour full or you will have to start over. It really wasn't as bad as it sounds.

TMCNo1
07-21-2007, 01:39 PM
The subject of bleeding brakes was discussed just last week and there are several options in it, just a different type of vehicle, but the same basic procedures and equipment, http://www.tmcowners.com/teamtalk/showthread.php?t=17799&highlight=brake+lines

P-hat_in_Cincy
07-21-2007, 10:10 PM
I can help...with pictures, but it'll probably have to wait until tomorrow.

In short: Starting with the furthest brake in the system (starboard on mine). There is a bleeder valve on each caliper. Open it. Run a hose up and then down into a catch pan (proper ID surgical tubing works great). Using a screw driver or the likes, find a pivot point on the actuator and pump the actuator (make sure the actuator reservoir does not get too empty and introduce are into the system). Fluid should come out the bleeder valve. Once clean fluid and no air come out, close off the bleeder valve and repeat on next furthest away caliper.

Disclaimer: Margaritas in the system tonight.

P-hat_in_Cincy
07-21-2007, 10:10 PM
EDIT: Double post.

JohnnyB
07-22-2007, 11:44 AM
I used one of these...

http://www.tooldesk.com/products/productDetail.aspx+id+994

I followed the instructions others have suggested which is to bleed the nearest brake to the master cylinder first and then move to the other. I had some issue with air leaking through the threads of the bleader so put some teflon tape around the threads at the top of the bleader.

P-hat_in_Cincy
07-22-2007, 11:22 PM
I followed the instructions others have suggested which is to bleed the nearest brake to the master cylinder first and then move to the other.

Well...that's directly opposite of what I read online when doing mine. Hmm...??? :confused: They worked perfectly today tho.

dmayer84
07-22-2007, 11:25 PM
If we are talking about bleeding the brakes on the trailer I took the actuator out by removing the c clips and then took a 12 inch socket extension and a socket to push in the cylinder while having someone else operate the bleeder on the brakes.

P-hat_in_Cincy
07-23-2007, 03:55 PM
Here are the pictures from when we bled the brakes after putting new calipers on.

You can see the bleeder valve (top brassy looking n1pple...is that an OK descriptor?) in this pic. The bleeder valves may be different than what is stock on MC trailers as these calipers were replacement calipers I was sent due to hanging of my left caliper.

Be careful with loosening and tightening the valves. You don't want to snap them off.

P-hat_in_Cincy
07-23-2007, 03:57 PM
Here we have loosened/opened the bleeder valve and attached a drain hose to it. I routed it up and then down so that when bleeding it will not draw air back into the system.

P-hat_in_Cincy
07-23-2007, 03:59 PM
And finally, here's the spot on the actuator we used to pump the brake fluid thru. Be sure to check the level in the reservoir often to make sure it doesn't get too low and put air in the system.

rektek
07-23-2007, 03:59 PM
I'd try gravity bleeding first, raise the master higher than the wheels.
open the bleeders and let them sit for several minutes while monitoring them, you'll be surprised this works much of the time, it's not a complicated brake line circuit. pressure bleeding would your next step.

P-hat_in_Cincy
07-23-2007, 04:02 PM
Never heard of it before. There are a lot of bends in the plumbing. Do you think it'd force air out of those bends?

93Prostar190
07-23-2007, 04:13 PM
just thought I would add my $ 0.02 ... I used an old cap from the reservoir off an older master cylinder and drilled a small hole and put in a female connector for my air compressor.

So now I can use my air compressor directly connected to the master cylinder and at 5PSI or so (light pressure) from the coupler side I can push brake fluid towards the calipers at the wheels.

That is how many race teams quickly change fluid and bleed during a race weekend. There are some 1 man bleeder kits out there from car makers which work with this principal.

Go to the wheel furthest from the master cylinder, open the bleeder valve with a nice piece of CLEAR tubing so you can see the fluid coming out .... look for their not to be any bubbles in the fluid ... you can also use a bit of oil on your connection at the bleeder screw to ensure that air is not entering at that point ...

Look for new clear fluid without bubbles....... close the bleeder from time to time to ensure your master cylinder still has plenty of fluid so be sure to stop and top off the fluid as you work your way through all your calipers from furthest to nearest.

If you want more detail let me know and I can take some pics.

Take it easy.

rektek
07-25-2007, 01:37 AM
Never heard of it before. There are a lot of bends in the plumbing. Do you think it'd force air out of those bends?

try it sometime, I've been able to bleed cars with complicated ABS systems this way, a trailer should be a snap as long as the bleeder screws are clean. I'll be doing my trailer this winter.

Kevin 89MC
07-26-2007, 05:23 PM
I have used my Mityvac for 10 plus years, bleeding dozens of brake lines on cars, trucks, cycles, trailers, etc. It's great - I can do it myself, and i've never had any problems with air in the lines. One of the better tools I've bought.
Good luck,
Kevin

stevenm2
07-30-2007, 09:40 AM
I am now going through this trailer nightmare as well my right rear brake locked up and got hot. would not release and I had to cut the brake line to relive the pressure. I hate these brakes! 04 trailer

P-hat_in_Cincy
07-30-2007, 10:31 AM
I am now going through this trailer nightmare as well my right rear brake locked up and got hot. would not release and I had to cut the brake line to relive the pressure. I hate these brakes! 04 trailer

Get in touch with your dealer and see what they rec.

Right/starboard side tho? Seems most are left/port side.

macattack
08-15-2010, 03:49 PM
Ref a 2005 MC trailer...it appears each brake caliper has two bleeder valves; does it matter which one you use to bleed the brakes? tks, mac

MarkP
08-15-2010, 06:18 PM
Ref a 2005 MC trailer...it appears each brake caliper has two bleeder valves; does it matter which one you use to bleed the brakes? tks, mac
Use the TOP one..

macattack
08-15-2010, 06:45 PM
markp...tks; I guess the obvious question I didn't ask the first time...do you know why there are two bleeder valves on each caliper? What's the purpose? tks

rektek
08-15-2010, 08:49 PM
markp...tks; I guess the obvious question I didn't ask the first time...do you know why there are two bleeder valves on each caliper? What's the purpose? tks

the caliper works on either side of the trailer, always use the top screw for bleeding.

macattack
09-05-2010, 10:38 PM
Ref 2005 MC trailer with a Reliable swing away tongue, model ACT-7.5KS...tried to bleed the trailer brakes following the directions in their Service manual; however, I could not get any fluid to exit the bleeder valves (tried both sides of the single axle trailer). The trailer tongue moves in and out, and the master cylinder was full, but rusty in color; also had some thick accumulations of stuff in the bottom of the reservoir. I remove all the fluid/sludge in the reservoir and refilled with new, but still would not bleed. I assume the sludge has clogged the ports in the master cylinder??? The next thought was to remove the master cylinder and take it apart/clean it out, but the 4 hex bolts holding it to the trailer are frozen. I used a box cutter around the hex heads and applied some WD-40; will let soak overnight.

First, am I on the right track and 2d any other thoughts on how to remove the hex bolts...tks, mac

macattack
09-26-2010, 11:36 PM
Finally got out the 4 bolts that were holding the master brake cylinder! Used a punch and hammer and patiently tapped the top of the heads counter clockwise until they broke free. I emailed Reliable and they do not stock a master cylinder rebuild kit:(. Does anyone have a source? tks, mac

rspiecha
09-27-2010, 11:03 AM
Check with Waymires Trailer Supplies (http://www.waymires.com/). I was able to get a replacement cap from them for my trailer, they also sell the complete master cyclinder also.

Rob

macattack
10-04-2010, 09:53 AM
just thought I would add my $ 0.02 ... I used an old cap from the reservoir off an older master cylinder and drilled a small hole and put in a female connector for my air compressor.

So now I can use my air compressor directly connected to the master cylinder and at 5PSI or so (light pressure) from the coupler side I can push brake fluid towards the calipers at the wheels.

That is how many race teams quickly change fluid and bleed during a race weekend. There are some 1 man bleeder kits out there from car makers which work with this principal.

Go to the wheel furthest from the master cylinder, open the bleeder valve with a nice piece of CLEAR tubing so you can see the fluid coming out .... look for their not to be any bubbles in the fluid ... you can also use a bit of oil on your connection at the bleeder screw to ensure that air is not entering at that point ...

Look for new clear fluid without bubbles....... close the bleeder from time to time to ensure your master cylinder still has plenty of fluid so be sure to stop and top off the fluid as you work your way through all your calipers from furthest to nearest.

If you want more detail let me know and I can take some pics.

Take it easy.

Interesting idea! Since I just replaced my master brake cylinder, I now have an extra reservoir cap. I would like to see a pic of your modified reservoir cap/the type of female connector you used. I guess 5PSI is not enough pressure to mess up any seals along the way to the bleeder valves?? tks, mac

Thrall
10-07-2010, 04:29 PM
The cheap 1 man bleed kits from the parts store work quite well on boat trailers.

craig3972
06-01-2011, 01:50 AM
Ref 2005 MC trailer with a Reliable swing away tongue, model ACT-7.5KS...tried to bleed the trailer brakes following the directions in their Service manual; however, I could not get any fluid to exit the bleeder valves (tried both sides of the single axle trailer). The trailer tongue moves in and out, and the master cylinder was full, but rusty in color; also had some thick accumulations of stuff in the bottom of the reservoir. I remove all the fluid/sludge in the reservoir and refilled with new, but still would not bleed. I assume the sludge has clogged the ports in the master cylinder??? The next thought was to remove the master cylinder and take it apart/clean it out, but the 4 hex bolts holding it to the trailer are frozen. I used a box cutter around the hex heads and applied some WD-40; will let soak overnight.

First, am I on the right track and 2d any other thoughts on how to remove the hex bolts...tks, mac
I have exactly this problem on exactly the same trailer tongue. I replaced the master cylinder, bench bled it, installed it back on the trailer and used a master cylinder cap with a schrader valve to pressure the system to 20psi until i saw new fresh fluid coming out of each bleeder valve. Still no @#%&* brakes... I am stumped, any ideas would be appreciated

93Prostar190
06-01-2011, 07:39 AM
I have exactly this problem on exactly the same trailer tongue. I replaced the master cylinder, bench bled it, installed it back on the trailer and used a master cylinder cap with a schrader valve to pressure the system to 20psi until i saw new fresh fluid coming out of each bleeder valve. Still no @#%&* brakes... I am stumped, any ideas would be appreciated

If the Master cylinder is working and moving fluid around (which it appears to from your post) then something with the adjustment of the brakes is the issue ..... pardon me I did not read back on all the posts ... does your trailer have drums? or disc? .... if drums ... let's talk adjustment next .... if discs .... maybe the rust is at the caliper as well and it is frozen so it cannot move ...

with the help of someone else, can you see the brakes actually moving at the wheel? spin the hub by hand with the trailer on a jack, and have someone activate the brakes by pushing at the tongue ..... can you see the movement?