Removing rust in manifolds when winterizing??

[scipper77]

Just drained my block (1985 3.8 liter mercruiser v-6 for what it's worth). Before I fogged I drained the motor and the manifolds had the usual rust/crud that had to be poked free to drain. I then put the plugs back in the motor and started up on the muffs to fog the motor. After fogging I drained the block again and there was just as much junk blocking the manifold plugs as the first time.

So my question is....

Is there any merit to filling and draining the block repeatedly until there is mo more debris in the manifolds???
Another way to ask the same question is does the crud do anything bad like restrict flow??

 

[tpenfield]

Re: Removing rust in manifolds when winterizing??

If you want, just run the engine on the muffs and open the drains and poke out the crud.

It is kind of futile, since the innerds will rust to no end.