Cleaning Exhaust Elbow

[Andibs]

Taken the exhaust elbow off for the first time and it's gunged up as I suspected. Read numerous threads on what to clean it out with, ranging from brick cleaner to coca cola.

What do the majority of folk use ?

Cheers

Andy

 

[Heckler]

Taken the exhaust elbow off for the first time and it's gunged up as I suspected. Read numerous threads on what to clean it out with, ranging from brick cleaner to coca cola.

What do the majority of folk use ?

Cheers

Andy

Dont use a sharp implement!

 

[Matata]

oven cleaner

 

[Scotsailor]

Caustic soda

 

[PetiteFleur]

I used a screwdriver which unfortunately went straight through the casting! Probably a good thing as it was obviously completely rotten, so had to get a new one.

 

[Andibs]

I used a screwdriver which unfortunately went straight through the casting! Probably a good thing as it was obviously completely rotten, so had to get a new one.

That's what I'm trying to avoid with my luck!!!

 

[Heckler]

That's what I'm trying to avoid with my luck!!!

I a, not a chemist, VicS is and I am sure he will come along shortly, but my knowledge from years ago says that acid is needed to dissolve the salts that mostly block the exhaust so I dont think caustic is any good! Brick cleaner is supposed to be good

 

[Major_Clanger]

Rydlyme, a dedicated product, works very well indeed but needs to be pumped around the raw water circuit for a couple of hours rather than leaving the elbow to soak in it. It'll dissolve anything nasty in the galleries.
http://www.rydlyme.co.uk/index.php/en/

 

[VicS]

I a, not a chemist, VicS is and I am sure he will come along shortly, but my knowledge from years ago says that acid is needed to dissolve the salts that mostly block the exhaust so I dont think caustic is any good! Brick cleaner is supposed to be good

Yes, up to a point. A hydrochloric acid based brick cleaner will remove carbonate scale but perhaps not quite so effectively when mixed with carbon and soaked in diesel

 

[ghostlymoron]

What are you hoping to dissolve? Soot or 'water scale'.

 

[Sandy]

Rydlyme, a dedicated product, works very well indeed but needs to be pumped around the raw water circuit for a couple of hours rather than leaving the elbow to soak in it. It'll dissolve anything nasty in the galleries.
http://www.rydlyme.co.uk/index.php/en/

How will this clean the elbow?

 

[RivalRedwing]

That's what I'm trying to avoid with my luck!!!

if it fails a screwdriver test then better to replace ... when and where would you like it to fail?

 

[Neeves]

Forget the carbon, or soot - it will not dissolve - or not in acid. The deposit appears to be primarily calcium salts, carbonate (it is simply discoloured with carbon). You need a fairly concentrated acid (I suspect most acids will dissolve calcium (carbonate?) - HCl is a good start. The blockage appears to be soot/carbon in scale - exacerbated by the temperature, salt water and maybe something acting as a catalyst. The soot/carbvon makes it look black - but, as it dissolves in acid, its not carbon that is the main issue.

Take the elbow off, on no account run concentrated acid through the system (I have no idea what else it might attack).

Place in a plastic bucket

If there are any flaws in the casting - they will be quickly exposed and the elbow will then be useless.

This will only work once.

Leave overnight - its not quick.

Keep anything of value well protected, hands, wife, children, pets and eyes. Think of how/where you are going to dispose of the production of your endeavours - its all pretty nasty.

You need copious clean water to soak the elbow afterwards. It will look pretty grotty - the paint will look manky. Providing there were no flaws - it will have a clean interior. If it works it will be, much, cheaper than a new elbow.

The biggest problems are flaws in the original casting, the acid will seek them out, and whether there has been a lot of previous corrosion - iron oxide will also dissolve in strong acid.

But it does work, once - say every 1,000 hours.

Jonathan

 

[oldgit]

Buy new one, they are not starship money, it will only clog again and probably when you most desperately need the engine.

 

[Andibs]

What are you hoping to dissolve? Soot or 'water scale'.

carbon build up by the look of it

 

[VicS]

Forget the carbon, or soot - it will not dissolve - or not in acid. The deposit appears to be primarily calcium salts, carbonate (it is simply discoloured with carbon). You need a fairly concentrated acid (I suspect most acids will dissolve calcium (carbonate?) - HCl is a good start. The blockage appears to be soot/carbon in scale - exacerbated by the temperature, salt water and maybe something acting as a catalyst. The soot/carbvon makes it look black - but, as it dissolves in acid, its not carbon that is the main issue.

Take the elbow off, on no account run concentrated acid through the system (I have no idea what else it might attack).

Place in a plastic bucket

If there are any flaws in the casting - they will be quickly exposed and the elbow will then be useless.

This will only work once.

Leave overnight - its not quick.

Keep anything of value well protected, hands, wife, children, pets and eyes. Think of how/where you are going to dispose of the production of your endeavours - its all pretty nasty.

You need copious clean water to soak the elbow afterwards. It will look pretty grotty - the paint will look manky. Providing there were no flaws - it will have a clean interior. If it works it will be, much, cheaper than a new elbow.

The biggest problems are flaws in the original casting, the acid will seek them out, and whether there has been a lot of previous corrosion - iron oxide will also dissolve in strong acid.

But it does work, once - say every 1,000 hours.

Jonathan

Hydrochloric acid is probably a good choice. It is readily available as brick cleaner ( although not all brick cleaners ) and less hazardous than other strong acids.

What concentration ( % HCl ) do you suggest ? Or would you use brick cleaner undiluted?

How would you suggest disposing of the waste? Would you suggest neutralising the excess acid, if so how?

 

[tim]

I used Wickes Brick Cleaner (neat) on my VP 2003 exhaust elbow. It only cleans up the calcium deposits (which it did very well), does nothing for the soot, and the real cause of the poor water flow was the rusting up of the waterways in the elbow.

 

[MM5AHO]

Here's mine when I replaced it. Almost completely choked off.

 

[Neeves]

I'd use brick cleaner undiluted in a plastic bucket. It is easy to neutralise, excess limestone, dolomite or chalk (the rock) works surprisingly well - and is available cheaply from most garden centres. You know when it is neutralised - its stops frothing.

If the buildup were only soot - it would not dissolve - acid will not attack carbon (carbon is inert to acid)

It will only work once, the second time the elbow also dissolves. Elbows here cost arounds Stg250 - its worth trying - if it is a failure you have wasted the cost of the acid and the limestone you picked up off the moors - if it works its good for another 1000 hours.