BX 16 Problems

DavidRutherford · Post by **DavidRutherford** » Wed Jun 27, 2007 8:48 pm

If you can't find a replacement manifold, contrary to popular belief, they can be welded. I've welded a couple of cast iron manifolds at work now, and they're fine.

But it does need to be by oxy-acetylene welding. Mig welding will just re-crack, and tig welding won't burn the corrosion off first.

jeremy · Post by **jeremy** » Thu Jun 28, 2007 7:01 am

Doc I agree - having tried to weld a Mini manifold with a mig - it just wouldn't take.

I understand the reason is carbon - there's loads of it in cast iron - and manifolds seem to be made of cheap stuff with loads of it in there.

With oxy-acetylene you will be able to burn out the carbon probably with excess oxygen (bright blue flame). An alternative I used when repairing bolt holes on a Jaguar exhaust manifold was to bronze weld (or braze).

I believe there are some specialist welding rods available for arc welding cast iron but they tend to be rather exotic like nickel or chromium and so are probably not easy to find.

So its probably possible to repair - especially if the affected area is well cleaned of carbon - the next fun bit is getting the bits aligned and holding them there while welding.

AlanS · Post by **AlanS** » Thu Jun 28, 2007 8:34 am

Cast iron isn't all that hard to weld if you get the right sticks to do it with.
Aluminium is also weldable using either an oxy or preferrably a Dillon which is oxy and LPG.
That's scarey stuff though; yiou sprinkle flux in powder form on the job and heat. When the flux goes molten, you hit it with the rod as it's at the right temp. Keep the flame there and the whole job just melts before your eyes just like magic!! redx

I think these days the magic word for aluminium is TIG and I'd be surprised if they couldn't do cast with this also.

Alan S

Post by **docchevron** » Thu Jun 28, 2007 11:58 am

jeremy wrote:Doc I agree - having tried to weld a Mini manifold with a mig - it just wouldn't take.

Thanks for agreeing, although it was David that mentioned oxy, not me!

tim leech · Post by **tim leech** » Thu Jun 28, 2007 4:49 pm

Trust me im no welding anything, im not allowed near anything combustable!

DavidRutherford · Post by **DavidRutherford** » Thu Jun 28, 2007 6:29 pm

No filling up with petrol for you then Tim!

Actually, I wouldn't expect you to do the welding, but if you can find a handy local bloke, a few beer tokens usually gets a little job like that done in seconds.

DavidRutherford · Post by **DavidRutherford** » Thu Jun 28, 2007 6:29 pm

Double post stutter removal service

mountainmanUK · Post by **mountainmanUK** » Thu Jun 28, 2007 6:34 pm

My local welding chappie fettled Monica's rear hanger in 5 minutes, for a crisp tenner in his hand! (He actually did the job in between 2 taxis who were already booked in! ):lol:

Edit: Sorry..posted this on wrong thread!

tim leech · Post by **tim leech** » Thu Jun 28, 2007 6:40 pm

I will replace it dave when I can locate one, as I have to take it off anyway I will exchange it Its cracked quite near the centre so has split all the way through.

classic2cv · Post by **classic2cv** » Thu Jun 28, 2007 7:21 pm

Hi Tim

yes they can be welded

if you can't get your hands on a new one and you can get it off without too much hassle

it may be possible to clean it up weld it and get it back on the same day

tim leech · Post by **tim leech** » Thu Jun 28, 2007 9:19 pm

If you can weld that is, bear in mind I normally glue my fingers together with anything remotely adhesive!

Post by **docchevron** » Fri Jun 29, 2007 2:35 am

Weld isn't adhesive mate. It will burn your flesh away very effectively, but it wont bond them!

Oxy really is the only way to go with exhaust mainfolds though.

Although I'll have to have a marathon welding sesh myself soon, I started looking round the valver and discovered it's as ripe as a pear!

So form an orderly que gents, small jobs will be considered whilst I'm up the farm replacing dead tin with shiny new stuff!
But not for a few weeks.

tim leech · Post by **tim leech** » Fri Jun 29, 2007 10:05 am

docchevron1472 wrote:
Although I'll have to have a marathon welding sesh myself soon, I started looking round the valver and discovered it's as ripe as a pear! .

So it snot just me then!

Post by **docchevron** » Fri Jun 29, 2007 11:36 am

Nope! I've neglected it too long.
It's creeping in everywhere! Even the bottom of the B pillar and into the sill. I've never seen a BX go there before.
Oh well, it'll excercise the MIG....