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Hey guys,

I have noticed some rust in my engine bay in a very hard to reach spot. It will be hard to treat it properly without taking the engine out.

I have used sandpaper and a bit of thinners to remove as much as I can and have gone over it with a tiny paint brush but there are definitely some areas I have missed (my hand does not fit)

I am planning on getting the engine rebuilt in a few years time and was wandering if there is anything I can do/use to prevent the rust from growing any further until I have the engine out and can do the proper treatment?

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Nah, shouldn't matter. I would take a stab and say you're only seeing a bit of surface rust, unlikely to be very deep. That said, get some fish oil on it and it will stop it from getting any worse.

You're kinda right. Fishoil coats the rust and surrounding metal which stops oxygen (in water) getting to it which is what causes rust.

It won't stop it completely, but will significantly slow it down. You need something to act as a sacrificial anode to stop it completely.

What does this mean? :P

You need something to provide the electrons to the oxygen instead of them coming from the iron that your car is made out of.

Rust happens when impure water steals electrons from impure iron (there are other reactions which can happen, but this is what's happening to your car). So a sacrificial anode will supply those electrons to the oxygen instead of them coming from your chassis rails :)

Where can I get me something to provide the electrons to the oxygen

Mmm....i don't think there's anything you can do. There are some electronic rust preventing devices around. In theory the make sense, but i don't think they've been proven to work in practice.

Try penetrol (available in spray can format) from bunnings etc.

The 4wd'ers love 'it. Some of them penetrol their bull bars and after 1 year of going off road and in salt water etc, no rust on their bull bars.

I tested some and it visibly repels water, pretty fun to play with lol. There's some other products from the same manufacturer but i think the spray can format will work best for you.. just aim and spray lol so no need to get your hand all the way in.

Where can I get me something to provide the electrons to the oxygen

Zinc

Any zinc rich primer, such as Zinc-it or cold gal will give you some cathodic protection. Otherwise use the POV anti rust and pour old engine oil over it every time you do an oil change. That's what we used to do in Finland to combat rust on the salted roads back when I were a lad.

Zinc

Any zinc rich primer, such as Zinc-it or cold gal will give you some cathodic protection. Otherwise use the POV anti rust and pour old engine oil over it every time you do an oil change. That's what we used to do in Finland to combat rust on the salted roads back when I were a lad.

Exactly.

Sand the surface rust back.

Spray some zinc rich primer onto onto the affected area. 2x coats.

Then a coat of under chassis paint.

If it's in a hard to reach spot ie. spray can cannot reach, just spray some paint into the can's cap and use a small brush to paint.

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