The following warnings occurred:
Warning [2] Undefined variable $search_thread - Line: 60 - File: showthread.php(1617) : eval()'d code PHP 8.1.31 (Linux)
File Line Function
/inc/class_error.php 153 errorHandler->error
/showthread.php(1617) : eval()'d code 60 errorHandler->error_callback
/showthread.php 1617 eval




Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
Metal Spray (Removal Of) - Exhaust Manifold
#1
I have a standard A7 cast iron exhaust manifold which appears to have been hot metal sprayed at one time (was that a "thing"? why?) Looks like aluminium or zinc coating, not sure how to tell. 

About 50% has fallen off, revealing the usual rusty cast iron beneath, thus posing the question of how to remove the rest. A wire brush only removed very loose bits. Picking at the edges does start to shift it, very slowly. Not sure if shot /sand blasting would do the trick? - my local blasting business has recently changed hands and gone somewhat 'up market'. Needless to say if it costs more than £20 I might as well just look for another manifold! 

Jon's acid bath perhaps?

Tempting just to squirt HT paint over it all but it will doubtless fall off before long.

Thoughts and clever ideas invited....
Reply
#2
(06-11-2021, 08:06 PM)Chris KC Wrote: I have a standard A7 cast iron exhaust manifold which appears to have been hot metal sprayed at one time (was that a "thing"? why?) Looks like aluminium or zinc coating, not sure how to tell... 

Metal-sprayed exhausts were all the rage in the 1960s. Aluminium-spray gave a nice clean white shade to your rusty exhaust; I favoured stainless steel spray which gave a dark metallic-grey effect. I don't think anyone gave any thought to what they might be like sixty years later!
Reply
#3
angle grinder or decent drill with a wire wheel on?
Reply
#4
If it is an aluminium coating Caustic soda solution will dissolve it but wouldn't attack the iron casting. The fumes will be really nasty though, soaking the manifold would definitely need to be carried well out in the open air.
Reply
#5
Thanks for your comments.

Mike - purely cosmetic then? Or did it make your car go faster?   Smile

Jon, I tried wire wheel in a drill, doesn't touch it. Angle grinder perhaps, but I've a feeling it will clog with the soft alloy, and will of course leave its mark on the iron beneath.

Stuart, caustic soda sounds like it might be worth a shot... I'll see what Wilko has to offer. And yes, out in the garden!
Reply
#6
blowtorch to get really hot on the surface and crack it off?
appreciating you don't want to crack it but if it is heading for the bin...
Enjoy yourself, it's later than you think!
Reply
#7
Yes, Chris, purely cosmetic:

   
Reply
#8
Good heavens Andy, nobody said the 'b' word! 
But suggestion noted - thanks.

Gosh Mike, that looks at least 10mph faster!!
Reply
#9
Oh, it was... until we put the rest of the bodywork back  Big Grin
Reply


Forum Jump:


Users browsing this thread: 1 Guest(s)