Rust in Motor

[AaronWhitt82]

Hey guys a quick question....
I finished Winterizing the boat today. Took off all the hoses and drain plugs in the motor to drain the water out then put them back on. I then took the thermostat cover off to dump a few gallons of RV antifreeze in her. The bolts on the cover still had the factory black paint on them so I knew it has never been off before. I noticed a good deal of rust inside. Also inside the hoses there was an orangish coating on them from the rust. I'm going to replace the thermosstat and gasket as well in Spring.
Just wondering if this is common or something I should be worried about? The motor is a 5.7 GM Indmar.
I'm the 2nd owner of the boat and the previous owner said all work was done by the dealer.
Also is there anything I can run through the motor to maybe help clean out some of the rust?

Thanks,
Aaron

 

[Don S]

Re: Rust in Motor

It's bare cast iron, rust is normal.

 

[ziggy]

Re: Rust in Motor

Also is there anything I can run through the motor to maybe help clean out some of the rust?

from what i get it's better to not try to clean it up as this just takes away some of the metal thickness and then the prossess starts happening all over again. this time it's (cast iron thickness) just thinner

I then took the thermostat cover off to dump a few gallons of RV antifreeze in her.

thats the best thing ya can do. winterinzeing with air is good, but anti freeze is better because it helps stop the corrosion that's takeing place when the block is dry. which it aint. damp, moist, air, rust........

i also understand that blocks don't generaly have a problem with rusting from the inside out to non servicable.......weather anti freeze, or w/ air......

that's the way i understand it anyways.....

 

[AaronWhitt82]

Re: Rust in Motor

Hey, Thanks alot for the replys guys.
I figured it was common to have rust inside since it is cast iron, but wasn't sure just how much.
I'm assuming the dealer just drained the block in the past for winterization since the factory paint on the thermostat cover and bolts is still brand new or it's just never been apart before to have any work or parts replaced which is nice to know.
I've read alot about guys just draining all the water out of the block for winterizing and leaving it as that and my Indmar manual also says to do the same.
I just wanted to be safe and dump about 4 gallons of RV antifreeze in to prevent further rusting and also to protect if there was some water left over inside the block that I didn't get out.
Thanks!

 

[crazy charlie]

Re: Rust in Motor

Sounds normal.Mine is the same color.Charlie

 

[crazy charlie]

Re: Rust in Motor

Sounds normal to me,mine has the same.Charlie