Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

(Some people have issue connecting. LEMON is investigating. For now, use Firefox or change your DNS server)

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Brake Fluid: Testing and Inspection

NOTE: Swollen rubber parts indicate the presence of petroleum in the brake fluid.

To confirm that contamination exists, make the following test:

Place a small amount of the drained brake fluid into a small clear glass bottle.
- Separation of the fluid into distinct layers will indicate mineral oil content.

If there is any question of mineral oil content, drain system, flush thoroughly and replace all rubber parts.