A simple question from a simple mind. I was going to check and refill the old stock undercab master cylinder if needed. Brake petal is depressing deep. How is the best way to check the brake fluid level and refill? At what level should the fluid be in the master cylinder and how is best to tell if it is there?


I do not have a lift and could jack it up - but felt that might cause the level to be off. It is not easy to get to and check and refill looks to be a pain.


Have not noticed any direct leak with the cylinder or brakes, but something seems to often be on the drive under the old stock engine/trans truck from one thing or another. Cylinder does not show any leak as far as I can tell in this bad weather crawling around under the truck.


Not sure how to refill easily and would rather not have brake fluid spilling and running everywhere.


I know this is simple for many of you - but suggestions would be appreciated from my end.


Bruce

 

How are you getting to the master cylinder? It sounds like you're trying to get to it from below, which would definitely be very hard. There should be a hole in the floor with a cover. If you go from the top, you should be able to just see the level. I usually fill er up as full as I can while being sure it doesn't spill out when you screw the cap back on. You can pour straight from the bottle of brake fluid, but you can use a funnel if you aren't confident enough. And make sure to rinse off anywhere the brake fluid may have spilled while you were pouring!

 

if it is completely stock, there should be a removable inspection plate in the cab floor above the MC. Remove the plate and unscrew the MC cover. Easy to check level and refill if necessary. Realize the OEM brakes are not self adjusting like later model drum brakes, so as the linings wear the pedal will drop. First try adjusting the brakes to see if the pedal returns to original height. (definitely do it before adding fluid to the MC). Ask if you don't know how, it's not difficult. You will need a jack, jackstand, possibly a creeper, lug wrench, and an inexpensive tool called a brake adjusting spoon. K D 287 Drum Brake Adjusting Tool 8" | eBay

 

I had never done anything to the truck's braking system since I bought it since all had been working ok and time was spent on pressing needs. The old original rubber mat on the cab floor had not been taken up (adhesive in places) except on the battery tray access area where I had done some work.


Actually did not know there was an access for the master cylinder in the cab floor until you guys pointed it out. Found it easily, checked and refilled with a small funnel and now have brakes and a strong brake petal action again.


As with everything on the old stock truck, I am learning thru trial and error. Seems more error most of the time. Not a mechanic and get frustrated at times, but learning as I go which to me is much of the fun of having the truck. All seems well right now and will watch for any leaks not noticed before.


Thanks,
Bruce

 

Good to hear you have brakes now. In the interest of safety, have the entire brake system, lines, hoses, cylinders and linings checked for condition. If by rare chance any of the components are original, they are questionable. Even if the brake system has been rebuilt a time or two, a safety inspection is suggested. The fact that your master cylinder required fluid indicates that there is a problem.. Remember, you have only one system and if you loose all fluid, you will have no brakes. Cold weather brings out the worse in brakes. Drive safely.

 

It normally stays outside, but I have it in a friends garage for a while so it can warm up and easier to check for leaks. Know they must be one somewhere.


Bruce

 

Are you sure you have a leak or the brakes just don't need adjusting?

 

Also while you're checking the lines, check to make sure there are no copper lines. They just can't handle the pressure required safely to run brakes. They're an easy to find, easy to make replacement line if you're a farmer and don't know better. I know my great-uncle (PO) at some point must have replaced one line with copper because I had to replace on right away when we started to tear at the brakes.