Technical Article

Hydraulic Brake Hoses

By John Wright, CCNEMGTR Technical Advisor

Some of you may know that I have spent the last several months of available time and energy preparing my Works MGA for the Collier Cup race last month.

This is a car with about 5400 original miles recorded, most of which are race miles I suppose. Of course, the barely functioning brakes were tops on the priority list and received a thorough inspection and overhaul.

Now, I have replaced many a hydraulic hose over time on MGs, but I never took the time to photograph a dissected one to show what happens after nearly 5 decades of even limited use.

The point here is for you to make it a point to know these things about your car. Most newer brake hoses have a date stamp. I am not sure when that was required, but if yours show no date, then you may want to think about replacing them (all 3 at the same time), if the age is uncertain.

The usual failure is one of hydraulic pressure not releasing when brake pedal pressure is released, causing brake drag. Another failure, much more dangerous but rare, is one of the hose actually separating from the end fitting. Not good on single cylinder systems!

See the below photos of my brake hose, which I split and opened up. You can see that the innards (technical term) have turned to jelly and could not possibly function safely or effectively.

Split Hose
Hose Cross-Section

Please check yours out at your next maintenance, if not sooner!