stripping and painting crankcases

[whiteylfc]

hi all.....I know this has been covered many times on here,but here goes.The engine that's going into my Phil Read Replica is badly flaked and I want it as close to original as possible before it goes back in the frame.I've split the crankcases to check out the internals and pulled out the crank and gears.Can anyone who has stripped and painted the crankcases advice me on the best way to do this.....

[Nurse Julie]

Try this link, http://www.sohc.co.uk/index.php/topic,10783.msg78781.html#msg78781

[K2-K6]

On the acid dipping issue,  probably those most accessible route available would be car wheel refinishers. They are usually running dip tanks for their purposes with both forged and cast alloy wheels, worth a chat to one to see if they can cover that stage for you.

[Trigger]

Most car wheel refurbishers use aqua blasting with sand in the system. Some have dip tanks but, the solution contains caustic chemicals. Beware

[K2-K6]

Is there a recipe for the acid solution you've used for cases that can be compared to that which the wheel places use.

I know some of the wheel refurbishers use blasting and wasn't suggesting that stage,  just that if they operate a suitable chemical strip stage then that would cover the logistic supply and safe use plus any disposal liability discussed in the other thread.

I may be forced into finding out what goes on with wheels anyway as about to get a car with properly horrendous wheel painting on it so could get a chance to get more info.

[K2-K6]

Just looking at what's out there and came across " ctc powder coating and acid stripping" they offer a specialist blasting to clean aluminium body panels which are recognised as fairly fragile by using a plastic media to clean the surface,  so maybe worth an enquiry.

[Trigger]

There is no point in any type of bead near an engine, that is surface treatment. The whole point in an acid dip is to remove all traces of paint and oil from the alloy because once you have painted it and it is up to working temp, any oil left in the casing of cast alloy will lift the new paint.

[AshimotoK0]

There is no point in any type of bead near an engine, that is surface treatment. The whole point in an acid dip is to remove all traces of paint and oil from the alloy because once you have painted it and it is up to working temp, any oil left in the casing of cast alloy will lift the new paint.

You are always telling us about this acid dip Graham ..but what is it ? Type of acid/trade name? so we can all give it a try !

[K2-K6]

Some of the wheel strippers seem to be using methylene chloride to do the job they require.

There are of course obvious safety issues in handling anything that has a useful capability in dissolving things like paint etc. I'm not advocating personal handling of stuff like this but more to pose questions to somebody operating in that area that may be able to work on the castings we are interested in.

It's interesting about oil inclusion in the crankcase also. Are they originally coated on the inside to prevent this happening and if so will this be removed during a strip and need too be refinished also?

[Trigger]

There is no point in any type of bead near an engine, that is surface treatment. The whole point in an acid dip is to remove all traces of paint and oil from the alloy because once you have painted it and it is up to working temp, any oil left in the casing of cast alloy will lift the new paint.

You are always telling us about this acid dip Graham ..but what is it ? Type of acid/trade name? so we can all give it a try !

I don't know what is in the tank Ash, Trade secret 

[AshimotoK0]

There is no point in any type of bead near an engine, that is surface treatment. The whole point in an acid dip is to remove all traces of paint and oil from the alloy because once you have painted it and it is up to working temp, any oil left in the casing of cast alloy will lift the new paint.

You are always telling us about this acid dip Graham ..but what is it ? Type of acid/trade name? so we can all give it a try !

I don't know what is in the tank Ash, Trade secret 

Come off it ..I reveal ALL of my trade secrets to everyone on here  ! 

[Aspro]

I was just about to have my cases vapour blasted, having read these posts perhaps I will go down the acid stripping line. Any advice on spraying the cases and barrel etc. would be appreciated.

[Nurse Julie]

Welcome Aspro.
Try the link further up this page (2nd post down ) and that will give you an idea. Feel free to ask as many questions as needed. It won't be me that tells you anything you don't already know but, others on the forum will I'm sure.