Brake Vacuum Booster
#1
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Brake Vacuum Booster
Hello All,
I just replaced my vacuum booster and I have gone from super hard brakes to super soft brakes. Not sure if its just the transition, but it almost feels like I have too much travel before I get pressure. Plus when I do get pressure its seems very soft, but I do stop. When I come to a full stop I can apply more pressure and there is still more travel before it reaches the floor. I believe It's my fault, I put the shim from the old on the new thinking that it was needed. I've also found information about adjusting the push rod in the booster, which I didn't do. Just looking for some advice on how I should remedy my issue.
Thanks
I just replaced my vacuum booster and I have gone from super hard brakes to super soft brakes. Not sure if its just the transition, but it almost feels like I have too much travel before I get pressure. Plus when I do get pressure its seems very soft, but I do stop. When I come to a full stop I can apply more pressure and there is still more travel before it reaches the floor. I believe It's my fault, I put the shim from the old on the new thinking that it was needed. I've also found information about adjusting the push rod in the booster, which I didn't do. Just looking for some advice on how I should remedy my issue.
Thanks
#2
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Did you open the hydraulic system at all to make the swap, or just unbolt the master cyl and set it aside?
There should be a rod you can adjust behind the master cyl. Sounds like it is adjusted too short.
There should be a rod you can adjust behind the master cyl. Sounds like it is adjusted too short.
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I got lucky and didn't need to open the brake lines to move the master cylinder out of the way. I even checked the pedal to see if there was air in the lines. They don't gain any pressure when I pump them, so I don't think they have air in them.
Do you or anyone know what the length needed to be or how many turns I needed to let out the push rod or is it more like trial and error?
Thanks
Do you or anyone know what the length needed to be or how many turns I needed to let out the push rod or is it more like trial and error?
Thanks
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#6
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In my original post, I didn't explain very well. When checking a manual on my vehicle is stated that the booster shouldn't need adjustment and that it would have already been adjusted by the manufacturer, hence why I didn't adjust it. I can see that now that you can't always trust everything you read.
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#8
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In my original post, I didn't explain very well. When checking a manual on my vehicle is stated that the booster shouldn't need adjustment and that it would have already been adjusted by the manufacturer, hence why I didn't adjust it. I can see that now that you can't always trust everything you read.
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You could measure the length of the old rod and set the new one to match, else it's trial and error.
#12
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I fixed 2 F-350s and a coupla XJs by adjusting the booster rod. Check it out some time. Easy to do. Wonder why the OP's instructions advised adjusting?
Last edited by cruiser54; 02-03-2013 at 03:11 PM.