Can you damage the engine by flushing while its still warm?

[Vee-ard]

As title says. Car isnt red hot just pulled up, but engine is still quite warm. Can you do any harm by flushing the block with the cold hose so soon?

[cander24]

It's definately NOT advisable to do this while its at running temp but most often will be fine. Your block is made from cast iron which does not like rapid cooling as it shrinks too quickly with cold water so you run the risk of cracking the block.

[The1]

i usually just mix in hot water when flushing so it's not a problem.

[justbad4you]

As above, use hot water when flushing,