Thread: brake problem

Tweet

I know this vehicle isn't a hotrod but thought I would ask here.
I bought a 92 F250 on an auction. Pretty sure it sat a couple years. It is dual fuel and I finally got time to get it running good on propane. I had driven it on gas too.
Anyway the front brakes get tight when I drive it. I did some tests and as soon as I got home I cracked a bleeder and there was no pressure built up. They seem to release fairly fast after I stop, usually. I checked the rod and it has no adjustment or stop on the pedal so I don't think it is applying pressure that way. I unhooked the vacuum and it didn't seem as bad but still there was some drag.
A few weeks ago I drove it out about 2 miles and it got so bad on the way home it would slide a front tire in the gravel on the shoulder of the road.
I drive it around the yard cold and apply the brakes several times with no ill effects. It seems to build pressure on it's own while driving. I'm a little baffled and can't afford to throw parts at it in the name of diagnostics. Any suggestions?

hello wb3 could be moisture in the brake fluid from sitting with cap off m/c brake fluid attracts water the water expands rapidly with temmp increase try flushing sys.buy a galon of breake fluid keep bleeding until you know all the old fluid is gone dont use fluid that has been sitting in your garage more than 6mo. to 1yr it most likley has moisture in it------- hope that helps ted

I have to agree with Ted that there is s pretty good chance of moisture. Also, the big Fords especially, have two guide pins that occasionally tend to lock up due to lack of good silicone brake grease. If it's an F250 4x4 Super Duty, be prepared to get dirty!!!! Pull those pins first of all. If they are dry or don't slide easily, you could try a new pair - but, IMO, get a pair of reconditioned calipers from someone on line like Rock Auto Parts and install. I just finished ~10 minutes ago, installing calipers on the rear my '06 F350 which has the same calipers as an F250. While there's a bunch of years difference between our trucks, the design is still basically the same.

I have priced some loaded calipers and the price isn't bad. I am sure I will replace those as soon as I can budget it. I hadn't thought of water in the system. I will attempt to flush it out but I do have a froze bleeded on one side. I knew the brake fluid absorbed it and started using the dot 5 years ago in my old cars that don't get driven regularly.
I have done maybe hundreds of brake jobs on the sliding pin Fords over the years and thought I was pretty familiar. I know they are more prone to drag than other designs. I have some residual drag but I can turn the wheels with my hands when I jack it up. It seems I can't get it home and jacked up in time to catch anything although when driving it the brakes may still be dragging hard after a cool down of 20 minutes or so.

Originally Posted by willowbilly3

I have priced some loaded calipers and the price isn't bad. I am sure I will replace those as soon as I can budget it. I hadn't thought of water in the system. I will attempt to flush it out but I do have a froze bleeded on one side. I knew the brake fluid absorbed it and started using the dot 5 years ago in my old cars that don't get driven regularly.
I have done maybe hundreds of brake jobs on the sliding pin Fords over the years and thought I was pretty familiar. I know they are more prone to drag than other designs. I have some residual drag but I can turn the wheels with my hands when I jack it up. It seems I can't get it home and jacked up in time to catch anything although when driving it the brakes may still be dragging hard after a cool down of 20 minutes or so.

If you have added DOT 5 to this system without a complete flush and replacement of seals from the MC to the calipers, you will have problems. Take a look at this: http://www.xs11.com/tips/maintenance/maint1.shtml

and this: http://www.type2.com/library/brakes/brakef.htm

It can actually be worse then this as these articles are soft pedaling it a bit. Some of the seals can actually swell with the combination of the DOT3/4 and the 5

Been there.....and you know the rest

I haven't added fluid and I don't mix the silicon fluid with the conventional. I merely stated when I rebuild a system I like to use it.
Tomorrow I will attempt to flush it with fresh Dot 4.

Originally Posted by willowbilly3

the conventional. I merely stated when I rebuild a system I like to use it.

....uhhhh, not really what you said, but no big deal

Why use DOT4 for flush when good ol' denatured alcohol is the recommended flush by brake component companies, a lot cheaper, a lot less messy, will dissolve sludge and carry out any water. Then fill with DOT3 or 4.

If the vehicle hasn't been driven for a couple years, it is most likely that the calipers are sticking on there mounts and not FLOATING as they were designed to do

If it is a hydraulic issue---the only prudent course to take is to completely redo all the seals/pistons/valves

And since it is a 1992 ----there are a couple areas that the steel line to the rear brakes rust out along the frame----

Originally Posted by IC2

....uhhhh, not really what you said, but no big deal

Why use DOT4 for flush when good ol' denatured alcohol is the recommended flush by brake component companies, a lot cheaper, a lot less messy, will dissolve sludge and carry out any water. Then fill with DOT3 or 4.

I appreciate all the advice. I really haven't been in the mainstream repair business for a few years now.
I've have noticed sometimes people really want to be helpful and sometimes they just want to prove how much they know.
When I have a fresh quart of brake fluid it is cheaper than the $5 worth of gas to drive uptown to buy alcohol (which I have never used, thanks for that tip).

I removed the calipers today and they moved freely on the pins. I emptied them out and bleed the system I haven't driven it since. It really needs a complete brake job, including hoses and at least one rotor. I will have to evaluate if it's worth the investment. I may just pull the propane system, ZF 5 speed and the tires/wheels and take the rest across the scale. It is a decent looking/running truck but has bondo and the odometer shows 200,000