r/AutoMechanic

I have someone that want to do side work on there car. As putting a starter in. My question is how much to charge them. They are getting the parts

There is a category of car maintenance that experienced mechanics call the boring critical work. Not the exciting repairs. Not the performance upgrades. The unsexy preventive maintenance that keeps a vehicle operating reliably and prevents you from being stranded somewhere inconvenient because something small and inexpensive failed at the worst possible moment.

Coolant hoses sit firmly in that category and they deserve more attention than most car owners give them.

Here is what they do. Your engine produces enormous heat when running. That heat has to be managed or the engine destroys itself. The cooling system circulates coolant, a mixture of water and antifreeze, through channels in the engine block to absorb heat, then out through hoses to the radiator where that heat is dissipated, and back again in a continuous loop. The coolant hoses are literally what connects the engine to the radiator and carries the fluid doing all that thermal work.

The failure modes matter. Coolant hoses are rubber and rubber ages. It gets harder, develops cracks, softens in others, and eventually either leaks or fails completely. A slow leak means your coolant level drops gradually and if you're not checking it the engine eventually runs hot. A sudden failure means you lose coolant fast and the temperature warning comes on quickly and if you don't stop immediately you're looking at serious engine damage that costs vastly more than the hose ever would have.

The inspection is simple. Squeeze the hoses with the engine cold. They should feel firm and slightly flexible. Hard and brittle means they're aging. Soft and spongy means the rubber is breaking down. Visible cracking is obvious. Any of those signs means replacement before failure not after.

A mechanic friend calls coolant hose replacement one of the highest return on investment maintenance items on older vehicles. He once showed me a failed hose from a customer's car that had clearly been repaired at some point with what looked like components from a generic parts bundle, the kind that used to come in those big Alibaba bulk orders that went around the trade.

It held for a while. Then it didn't.