[Zmb524]

I have a 1997 jeep wrangler and i replaced the two front calipers because it was pulling to the left when i braked hard. I then decided to look at the back and replaced the wheel cylinders and shoes. I have tried to bleed them many times and i just keep getting air. I then replaced master cylinder same thing. I do not see any leaks what could it be. Please help.

 

[Pmryall]

Well. If the new master cylinder is good and hooked up to the brake pedal. And your absolutely sure that there are no leaks anywhere. Once you've pushed all the Pistons back on the calipers and you've bled the brakes properly it does take a few pumps to get the Pistons in the cylinders to push back out properly. So pump the brakes a few more times see if that changes anything. Have you bled brakes before? Your sure it's done properly with no air in the system? My father always taught me to do the farthest wheels first. So passenger rear, driver rear, passenger front, driver front. Make sure that master stays full so you don't suck in more air. It can seem like it takes forever.

 

[DP40]

When I replaced my calipers, I left the bleed screw open and for the most part the system bled itself. Just watch the fluid level in the reservoir. Start to bleed from the farthest wheel which will be the passenger rear, then driver rear, then passenger front, then driver front. do them in that order. Its gonna take 2 people to do it properly. Don't forget to have plenty of brake fluid on hand.

 

[woody109]

New master cylinder may need to be bench bled too.

 

[Water Dog]

New master cylinder may need to be bench bled too.

^^^For sure. You should have bled the master cylinder before installing.

 

[mattstj]

How does one bleed it before the brake fluid runs through it.

 

[Water Dog]

How does one bleed it before the brake fluid runs through it.

Clamp it in a bench vise, fill it with fluid, use your fingers to plug off the outlets (with a pan under it), and slowly pump it by hand until the air works out and all you have is fluid bubbling up, then install and finish by bleeding the entire brake system starting with the wheel furthest away from the master cylinder and work towards it.

 

[HiTech]

Brake problem

Your calipers are reversed! They will fit even if they are on the wrong wheel. You will never be able to bleed all the air out.

Look at the bleed valves ,they look almost centered but one is higher.
I did the same thing.....

 

[Zmb524]

Thanks for all the replies. I have the calipers one the correct sides with the bleeder screw on top. The back brakes are fine they have no air in the lines but the front just seem to keep getting air in it. I see no visual leaks but how else could i tell if a line had a puncture. I also bench bled the master cylinder. I had someone help that used to be a mechanic so i know i am bleeding them right. What else could it be. I drove it out of garage today and i have no brakes at all. Like no pressure on pedal. Thanks

 

[Philmycrackin]

Your calipers are reversed! They will fit even if they are on the wrong wheel. You will never be able to bleed all the air out. Look at the bleed valves ,they look almost centered but one is higher. I did the same thing.....

This was my guess. I did the same thing. LOL

 

[AUJeeper]

I would recommend a Motive Products power bleeder-basically a garden sprayer tank with a conversion kit to hook up to your master cylinder reservoir. It will push the air out.
If you don't do that then take a container and fill it with brake fluid and sit it by the caliper you are bleeding (start furthest away from M/C) put the end of a clear vinyl hose in the container with the end completely covered in fluid-place the other end on the bleeder screw(it should fit tightly) then open the bleeder and then rapidly pp the brake pedal down to floor and back up. These long rapid strokes tend to allow the system to burp better than they typical brake bleed. I would recommend a block of wood on the floor so your pedal doesn't go too far possibly damaging the master cylinder.
Again though I would recommend the power bleeder. Both options I give you can be done by one person

 

[norville]

I usually lock the rear drums up with the adjusters to get the air out of the rears. It stops the brake cylinders from moving. I've had many all drum vehicles and this was the only reliable way to remove the air from the lines.

Next even though I have a used a hand pump a check ball valve hose and gravity bleed. A helper pumping the brakes while I crack the line seems to work the best. less of a chance of air bleeding back into the system around the bleeder valve. I generally gravity bleed them first so there is fluid near the end of the line. I then use the check ball bleed hose and an old bottle of fluid.

That gets most of the lines free from air, I often bleed them one more time after driving around a few days.. I just did this on a dried out system, no issues..

Did you use new copper gaskets at the banjo fitting? Was the area clean?

bob

Bottom line is get helper....