Mercuiser rust through thermostat housing

[enderl25]

this is my first post. i just acquired my dad's 86 searay 5.7L mercuiser 260 with alpha one. this fresh water boat sat unused and dry docked for the past 5 winters. when the boat was originally layed up, pink antifreeze was pumped into the engine from a bucket through muffs placed appropriately over the outdrive intakes.

i drained the system this weekend and found rust throughout the thermostat housing, and a little rust on the belt surface of the power steering pulley and cooling pump pulley. i am trying to determine how serious these conditions are before i start dumping money into new parts.

questions:

1. is the rust and scaling in the thermostat housing a big problem?
2. do i need to replace the thermostat housing?
3. what can be done to flush or remove rust from the system?
4. do i need to replace the pulleys?

pictures of the thermostat housing attached for reference.

ender



001.jpg



002.jpg



001.jpg

 

[TilliamWe]

Re: Mercuiser rust through thermostat housing

The thermostat housing rust, while not ideal, is pretty normal, and unless when you scrape it out it pokes a hole in the housing, it doesn't need to be replaced.
As far as flushing it out, just use the boat, that'll be the best thing for it.
Just lightly scrape off the pulleys and use the boat. It might prematurely wear out the belt on there now, but consider that a "sacrifice". The belt should help "clean" off the rust, then put on a new belt.