Penetrating oils – how do they compare?
The classic car fraternity is often faced with bolts that are difficult to release with the consequent fear that increasing effort will result in the bolt shearing which then leaves many DIY enthusiasts with a major difficulty – extracting a thread. So using a rust release agent or penetrating oil to help free a seized bolt thread is a sensible option, but which product is likely to be the most effective? The modest additional cost of a release agent that performs well in releasing a seized thread is well worth bearing but also you need patience and restraint so you do not apply too much force in attempts to free a thread.
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