This Forum is a place for Piper Comanche pilots to communicate and discuss technical issues
If you join or reset a password, please check your Spam Email box for emails from Admin at ComancheTechTalk.com
Please put your questions on the forum as well so everyone can read and respond. Someone else might be having similar questions.
All questions or topics on the Forums automatically get sent to the Tech team as well.
My brakes work when on the ground parked or taxi. Once I take off, travel at 13k feet, when I extend gear and land, I have lost pressure and have to pump the toe brakes or hand break. Had the system bleed but no changes . Any help out there?
Steve:
What you describe sounds a lot like air in the brake lines. I note that you mention having the system bled but, depending on the brake system you have, this can be difficult to do correctly. Sometimes the best approach is to pump oil up from below rather than push it down to the calipers.
William
definately sounds like air still in system and push back bleed is going to be the best way to get them bled out
Mike
Hi Steve,
You have been given good advice. I don't think there is much doubt you have air in the brake lines and they need to be bled properly. I agree with William and Mike. I would only add one thing. Once in a great while you will see a recalcitrant brake system that defies normal bleeding procedure. I have seen two of them over the years. Brakes where you would pump a gallon of hydraulic fluid through them and still have air in the system.
Probably 15 yrs ago an older mechanic on the field told me when that happens, go to a hardware store and buy a one-gallon bug sprayer. The one I got at Northern Tool cost $10. It was shaped like a small pot-bellied stove and had a pump handle on top to build up pressure in it. And there was a rubber hose with a handle on it. I cut off the handle where the bug spray came out and made the rubber line adapt to the brake system.
When I hooked it up to the brake line from below I could really put some force on the brake fluid. And it worked. If the conventional methods don't work (and they do most of the time), at least you will have a plan B.
Good Luck,
Dave Clark
