De-coke with caustic soda

[phil38]

Just cleaned up my old microns after a few years hanging up in the garage. Was expectng them to be is a poor state under all the dirt and oil, but the chrome is in pretty good nick.

Normally, I'd use the hot air gun method for a thorough de-coke, but this will probably take the chrome off.

How effective is caustic? What's the right concentration. And what's the best way to plug the ends?

[shaunthe2nd]

I decoked 2 pairs using caustic soda and was happy with the results.
Can't remember what concentration I used though, I seem to remember I made it quite concentrated as I didn't want to have to repeat.
Filled the pipes up and left them to sit for about 5 days.
I plugged the ends of standard cans using lids off spray cans. - see the following thread...

rdlccrazy.proboards.com/thread/25554/tip-week

I also found it easier to bolt the 2 exhausts together it made them a bit more stable whilst filling etc.

[Deleted]

If your pipes are chromed and you want them to stay that way don't use caustic, it will dissolve the chrome quite readily if spilt on it,even at low concentrations

[phil38]

Sept 22, 2014 15:06:41 GMT 1 @hblair said:

If your pipes are chromed and you want them to stay that way don't use caustic, it will dissolve the chrome quite readily if spilt on it,even at low concentrations

Really? Didn't know that.

Any recommendations. Haynes manual says to use petrol, which I guess will dissolve anything oily.

[steven]

Hi,
I did a set a couple of months or so back too, the quantaties and concentrations are in the post somehwere, its a bit long winded, but hopefuly you will find what your looking for.

I didnt know that it fooks chrome either, which is good to know, as Iv got a set of origonal, from back in the day "Codnor Microns" to do too at some point as well.

steven.

rdlccrazy.proboards.com/thread/27552/spannies-de-coke?page=1&scrollTo=245796

[yazza54]

Just don't get it on your skin, eyes etc. evil shit

[simoniz]

I did my last de-coke of a chromed pipe with paint stripper - put a bung in one end, filled up the pipes to the top and let them sit for a week. Gave them the occasional shake to move the liquid about. Tons of nasty clag came out after that.

[Deleted]

+1 for yazza, it burns badly, very badly, I know, I've been sprayed with it and it ain't fun washing it off in the middle of winter under a safety shower I can tell you and don't use it on Aluminium either it will dissolve it

If you go the paint stripper, find one that contains NO caustic soda (it will probably say Sodium Hydroxide) they are available,it should contain methylene chloride (or Dichloromethane as it is sometimes called) and you can use that on aluminium and chrome to remove carbon and paint, it just smells bad

As always try a bit on some useless chromed object (ie old escort or leyland bumpers) to see what the result will be before using it on your prized chromed exhausts

And remember "If all else fails read the instructions"

On a warm summers day out in the bush, if you are quiet, you can even hear the Ford's rusting

[johnlc]

Was told you can use an old brake cable or speedo cable with one end frayed out used in a drill

[phil38]

Sept 23, 2014 16:43:20 GMT 1 johnlc said:

Was told you can use an old brake cable or speedo cable with one end frayed out used in a drill

Might try that. Not keen on caustic in case it leaks out, same for petrol.

Burning out works best and is easy, but not a good plan unless the exhausts are going to be repainted or plated.

[bogey]

That frayed cable trick sound good. I reckon I will give that a try.