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Nine Tips For Repairing Brakes

I bet most of the cars, trucks and equipment you drive have good brakes. But often one or two units on the farm are a bit questionable, whether it s the old truck you use just for hauling water or the fuel truck that only runs when you re working the fields. On our farm, a lot of our vehicles and equipment are older in fact, most of our equipment is 20 or 30 years old and our oldest truck will be 50 next year.

As long as they are working, brakes are an easy thing to forget about until the day your foot hits the floor and you cry out, Why won t this thing stop?

When I started farming back at the dawn of time, a truck was old and outdated when it was 20 or 30 years old. Typically it wasn t used much past that age as new (or newer) trucks were reasonably priced. Also, the technology in vehicles and machinery had changed so much that the old ones were technically obsolete.

Fast forward to 2011. Really nice grain trucks that are 30 or more years old are still bringing $10,000 or more at auctions while tractors built in the 70s are still used on many farms. The technology in trucks and tractors hasn t changed significantly since 1975, so a good unit from those years still has a place on today s farm. But is it still safe?

Do you know how old your rubber boots are? I often ask this question to our customers when they are wondering why the brake system on this nice 30-plus-year-old truck is suddenly needing a lot of work. Brake systems have rubber seals and hoses that are put under pressure every time you push the brake pedal.

To top it off, most brake fluids absorb water. If you haven t changed the brake fluid, it will have moisture in it because of condensation within the brake system. That moisture is busily corroding the innards of your brake cylinders and lines.

DIFFERENCES IN BRAKE SYSTEMS

Back in the old days (1920s) a lot of brake systems were mechanical. Hydraulic brakes were quite an improvement and became common in the 1930s. These were a single system brake system which only had one reservoir. This system was used up until about 1970 in many cars and trucks. Most two-and three-ton trucks waited until the 80s to get dual systems. The problem with a single system is that any fluid leak in the system means that you have no brakes. This was not very safe, and that s why most, if not all, new vehicles have dual systems.

With a dual system, you have two separate brake systems on a vehicle, typically one for the front brakes and a second for the rear brakes. If one system develops a leak, you have a backup. If either system is leaking, the brake warning light goes on. But this system is not foolproof. (They say fools are too inventive.) If the warning light does not work or if you ignore it, you can still get to the point of losing brakes entirely.

How do you tell if you have a single or dual system? Look at the master cylinder. If it has two lines coming out of it it s likely a dual system. The reservoir will likely have one cover but two compartments inside. Some older trucks, such as our 1962 GMC, have two lines coming out of the reservoir but it is still a single brake system. One line is for the brakes and the other is for the hydraulic clutch. A dual brake system will have two steel lines from the master cylinder going to the brake system.

FOUR TIPS FOR SAFE BRAKING

1.Before you drive any vehicle, car, truck or implement always check the brakes before you move the unit. This is especially true if you re not familiar with the unit or if it has been sitting for a while.

2.If the unit is equipped with brake warning lights check that are they working correctly. Do they light up when you start the vehicle and then go out? This is the way most of them work. If they don t light up, the bulb could be burnt out and then you have no warning system. If the light stays on, look for the cause of the problem.

3.Is the brake fluid reservoir full? If not, fill it to the required level with proper brake fluid. Only use brake fluid! Many brake systems have been ruined by putting in wrong fluids, such as hydraulic oil.

4.When you drive does it stop straight when the brakes are applied? Are there any grinding noises when you apply the brakes?

NINE TIPS FOR BRAKE REPAIR

A complete brake repair training session would fill a book, so you re getting just a few repair tips today. If you re not confident that you can do this work yourself, then get someone who is competent to do it for you.

The first grain truck I bought in 1975 was a 1950 Ford two-ton. I bought it at an auction for $1,200, and the brakes were weak. I was a bit shocked by the $800 bill for fixing the breaks (a new car in those days went for $4,000) but for the 15 years we used that truck, the brakes were always good.

Here are a few tips and ideas for repairing your brake system.

1.Replace rather than rebuild. You can get brake cylinder and master cylinder kits quite cheaply, but if we are doing work for a customer it is almost always cheaper to put in a new or rebuilt unit than it is to put in a kit. If you are doing the labour yourself it might be cheaper to use a kit but we ve found that if the unit is 20 or more years old, then invariably the cylinder is rusty and a hone won t clean it up enough to make the repair last.

2.If you can t get a rebuilt cylinder you can get them re-sleeved. The last one we had to send to Ontario to get re-sleeved.

3.Check the hoses for cracks, bubbles or wet spots. If they look suspicious, replace them. Also, we ve had an occasion where the hose looked good on the outside but had failed on the inside because it would not let the fluid back to the master cylinder. After putting on two disc brake callipers, we found the problem.

4.Brake boosters also cause a lot of problems. Most of the grain trucks we work on have a vacuum booster either on the firewall or under the floor. These are readily available rebuilt or you might find a good used one. Make sure the vacuum check valve on the vacuum hose is good, otherwise you will get gas fumes in your booster.

5.If your brakes are sticking, look for a sticky residual pressure valve in the master cylinder or brake booster. aaThis can sometimes be taken out and cleaned. Another cause could be rust and junk in your brake fluid not allowing the brake cylinders to return.

6.Check out your steel brake lines, too. They should have a grey colour. If they are rusty looking, give them a wiggle to see it they are weak and needing replacement. Any damp spots on the lines could be leaking brake fluid. Clean any build-up of mud off the lines and if they have surface rust, a shot of Rust Chek or any other rust preventive spray won t hurt. We ve seen rusted through steel brake lines on trucks that weren t even 10 years old.

7.Ordering parts can be a bit of a dance. Many grain trucks used two or three different brake systems in the same year on the same model. You ll almost always have to get casting numbers from master cylinders. (See Photo 1). This one is located on the underside of the master cylinder. (I wonder if they have classes on how to put the casting numbers in the hardest possible place to read.)

8.The brakes on the wheels will often have to be taken apart to find out what parts are needed. Again, two types of brakes may have been used on similar trucks.

9.For vacuum brake boosters you will need the tag number. It is located on the ring that holds the big drum together. (See Photo 2.) Sometimes this is missing so you have to order by application.

RonSettlerfarmswithhiswifeSheilaand theirsonsBenandDan.Theyalsooperated arepairandsalvagebusinessatLuckyLake, Sask.YoucancontactRonat306-858-2681or emailat [email protected]

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