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De Rusting an Engine Block
AntonUK - 9/4/18 at 07:47 PM

Hi All,
Ive acquired an old mini A-Series engine block which I am planning to do the Engine Block table project with. (I have a little history with said block, it was the first engine I managed to terminally break over 10 years ago)

Problem is that it is covered in surface rust from sitting in a friends garage for years.

Does anyone have any experience with de-rusting a block successfully? There are a number of "special bottles" available online but wanted a more locost way.


Thoughts?

perksy - 9/4/18 at 08:21 PM

Rotary wire brush in a drill has always worked well for me

gremlin1234 - 9/4/18 at 08:46 PM

there is a very long running thread on electrolysis
https://locostbuilders.co.uk/viewthread.php?tid=9158&page=0

snapper - 9/4/18 at 09:12 PM

You’ll still have to wire brush it after electrolysis as it will have a flat grey look.
I would give it a wire rotary brushing and see how a bit of it looks
For the authentic A series look a quick wizz off the surface Rust and green smoothright then soend sone time making the bores smooth metal for either the scotch bottles or the slow flashing red led’s to simulate the firing order

joneh - 9/4/18 at 09:29 PM

I went through this process. My local engine rebuilder put it through his acid dip for £20. Saved making a mess at home.

Shooter63 - 10/4/18 at 05:33 AM

Molasses and water is supposed to work well, 3 parts water to 1 part molasses, leave it in a tank of the mixture for a few days and rinse off. It won't remove grease etc but the rust should be gone.
I haven't tried it but have seen it recommended
Looking about the best place to buy it seems to be equestrian places around £10.00 for 5lts

Shooter

nick205 - 10/4/18 at 07:59 AM

quote:
Originally posted by joneh
I went through this process. My local engine rebuilder put it through his acid dip for £20. Saved making a mess at home.



My local engine reconditioner did this on my Pinto engine when I rebuilt it for my MK Indy. IMHO a cheap, fast and painless process and the block came out looking good. Being cast iron I gave it a couple of coats of Halfords red engine block paint to prevent it going rusty again once in the Indy.

BenB - 10/4/18 at 09:53 AM

quote:
Originally posted by Shooter63
Molasses and water is supposed to work well, 3 parts water to 1 part molasses, leave it in a tank of the mixture for a few days and rinse off. It won't remove grease etc but the rust should be gone.
I haven't tried it but have seen it recommended
Looking about the best place to buy it seems to be equestrian places around £10.00 for 5lts

Shooter


It works well. I used it on some well rusted nuts and it took the rust off nicely. I think there's even a picture in my photo archive of it.

found them...




to



after a day with no additional processing.

miskit - 10/4/18 at 01:26 PM

Citric acid made up from cheap ebay powder is the usual solution (if you will excuse the pun) - if you don't want to use electrolysis which would be my first choice.

CosKev3 - 10/4/18 at 02:51 PM

If you've got a container big enough to soak it in get some Bilt Hamber Deox-C powder,you mix it with water and it's awesome stuff!

Angel Acevedo - 10/4/18 at 03:17 PM

quote:
Originally posted by AntonUK
Hi All,
Ive acquired an old mini A-Series engine block which I am planning to do the Engine Block table project with. (I have a little history with said block, it was the first engine I managed to terminally break over 10 years ago)

Problem is that it is covered in surface rust from sitting in a friends garage for years.

Does anyone have any experience with de-rusting a block successfully? There are a number of "special bottles" available online but wanted a more locost way.


Thoughts?

How thorough a de-rusting do you need?
If it is going to be stored/displayed indoors and you are going to paint, hand metal brush, degrease, rust converter and topcoat may suffice.
If you want shiny surfaces, a more dedicated method may be needed.
For bores, I´d use a cylinder hone (an old one would be enough)
HTH.

nick205 - 11/4/18 at 07:54 AM

Assuming you're not going to be using the block as part of an engine in future then you could get it shot blasted. There's plenty of places that do it and you'd end up with a clean exterior afterwards ready to paint.

Slimy38 - 11/4/18 at 11:58 AM

quote:
Originally posted by CosKev3
If you've got a container big enough to soak it in get some Bilt Hamber Deox-C powder,you mix it with water and it's awesome stuff!


Seconded, I've used it for all my donor parts and they've all come up really well. The only thing is that you do need to clean them afterwards, so there is still a messy manual part to the task. I had hoped it would be like the ads where you drop it in the tank and it comes out the following day all shiny and ready to go!

CosKev3 - 11/4/18 at 02:36 PM

quote:
Originally posted by Slimy38
quote:
Originally posted by CosKev3
If you've got a container big enough to soak it in get some Bilt Hamber Deox-C powder,you mix it with water and it's awesome stuff!


Seconded, I've used it for all my donor parts and they've all come up really well. The only thing is that you do need to clean them afterwards, so there is still a messy manual part to the task. I had hoped it would be like the ads where you drop it in the tank and it comes out the following day all shiny and ready to go!


What have you had to clean afterwards?just rinse off in fresh water you mean?

If you've had to do more than that you've not been using a strong enough mix!

Slimy38 - 11/4/18 at 07:53 PM

quote:
Originally posted by CosKev3
quote:
Originally posted by Slimy38
quote:
Originally posted by CosKev3
If you've got a container big enough to soak it in get some Bilt Hamber Deox-C powder,you mix it with water and it's awesome stuff!


Seconded, I've used it for all my donor parts and they've all come up really well. The only thing is that you do need to clean them afterwards, so there is still a messy manual part to the task. I had hoped it would be like the ads where you drop it in the tank and it comes out the following day all shiny and ready to go!


What have you had to clean afterwards?just rinse off in fresh water you mean?

If you've had to do more than that you've not been using a strong enough mix!


It had a dark 'slime' on it, it came off with water and a scourer but it stuck to everything. My hands were black, the sink had a tide mark, it was horrible!