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Omega Help Area => Omega General Help => Topic started by: JamesV6CDX on 02 October 2013, 17:12:17

Title: Welding manifold?
Post by: JamesV6CDX on 02 October 2013, 17:12:17
I can't seem to get a used manifold anywhere. Mine has a pretty clean long crack on top. Can they be welded?
Title: Re: Welding manifold?
Post by: JamesV6CDX on 02 October 2013, 17:12:51
Exhsust manifold by the way...
Title: Re: Welding manifold?
Post by: dad1uk on 02 October 2013, 17:33:41
They can but I think it needs special rods and or welder......
http://www.mig-welding.co.uk/cast-iron.htm
Might help James..... means nothing to be but then again no surprise there ;D ;D
Title: Re: Welding manifold?
Post by: serek on 02 October 2013, 17:50:50
I can't seem to get a used manifold anywhere. Mine has a pretty clean long crack on top. Can they be welded?
with out any problems
think mig welder should do job
Title: Re: Welding manifold?
Post by: chrisgixer on 02 October 2013, 20:29:16
Are they cast iron? If so get a professional welder on it. Which will mean removal I would have thought.

Roger Clarke is the man in Reading when it comes to welding. He'll moan it can't be done etc, then proceed to do a top notch job. ::)
Title: Re: Welding manifold?
Post by: Andy B on 02 October 2013, 21:13:58
When welding cast iron, I'd say that you need to use a 'stick'/arc (MMA) set, with a cast rod but you have to heat the manifold up first, otherwise, because of thermal shock, you'll end up with a nice crack along side your nice new weld ....... been there - done that a few times in the past.  ;) ;)
If you're paying someone else to do if for you, I reckon that cost wise, you'd be better off with A N Other manifold .... obviously assuming you can get hold of one.
Title: Re: Welding manifold?
Post by: serek on 02 October 2013, 21:17:29
are we talking about 3.0 manifolds or 3.2
as this to different type of steal
Title: Re: Welding manifold?
Post by: Steve B on 02 October 2013, 22:55:46
are we talking about 3.0 manifolds or 3.2
as this to different type of steal
2.2  :y
Title: Re: Welding manifold?
Post by: Marks DTM Calib on 03 October 2013, 09:40:54
There a nightmare to weld!

Hi Carbon arc rod is what is required.

The only thing working in your favour is that your not looking for a structualy strong weld, just a gas tight one.
Title: Re: Welding manifold?
Post by: symes on 04 October 2013, 22:07:06
if anybody notices this---Frost Restoration--they do a special stuff for cracked manifolds and blocks-dont know why i bother as nobody ever checks out---have used the stuff on mine and guess what--------it works---and maybe thats to simple
Title: Re: Welding manifold?
Post by: steve6367 on 04 October 2013, 22:41:03
This one?

http://www.frost.co.uk/j-b-high-heat-adhesive.html (http://www.frost.co.uk/j-b-high-heat-adhesive.html)
Title: Re: Welding manifold?
Post by: cnj on 05 October 2013, 07:15:15
does anyone know whether you have to clean the crack/split before applying, if so what would you use ?
Title: Re: Welding manifold?
Post by: Andy H on 05 October 2013, 08:11:04
if anybody notices this---Frost Restoration--they do a special stuff for cracked manifolds and blocks-dont know why i bother as nobody ever checks out---have used the stuff on mine and guess what--------it works---and maybe thats to simple
Are these the rods? http://www.frost.co.uk/automotive-welding-tools/hts-528-brazing-rods.html (http://www.frost.co.uk/automotive-welding-tools/hts-528-brazing-rods.html)

They describe them as brazing filler rods so I assume you need oxyacetelyne kit to use them :-\
Title: Re: Welding manifold?
Post by: tunnie on 05 October 2013, 08:14:53
if anybody notices this---Frost Restoration--they do a special stuff for cracked manifolds and blocks-dont know why i bother as nobody ever checks out---have used the stuff on mine and guess what--------it works---and maybe thats to simple
Are these the rods? http://www.frost.co.uk/automotive-welding-tools/hts-528-brazing-rods.html (http://www.frost.co.uk/automotive-welding-tools/hts-528-brazing-rods.html)

They describe them as brazing filler rods so I assume you need oxyacetelyne kit to use them :-\

This stuff more looks like average goo through?

This one?

http://www.frost.co.uk/j-b-high-heat-adhesive.html (http://www.frost.co.uk/j-b-high-heat-adhesive.html)

Be interested to see if it works, as I think FatherT's manifold has a crack. As it's noisey when cold, fine when hot.
Title: Re: Welding manifold?
Post by: omega3000 on 05 October 2013, 12:57:10
does anyone know whether you have to clean the crack/split before applying, if so what would you use ?

No expert but i thought the crack had to be ground into a V for the weld  :-\
Title: Re: Welding manifold?
Post by: Andy B on 05 October 2013, 13:06:50
......
No expert but i thought the crack had to be ground into a V for the weld  :-\

Ideally yes, you get better penetration that way, but on something like the outside of a manifold it's perfectly acceptable to build the weld up & leave it. A weld prep is needed in places where you'd need to grind the weld back flush again eg on the mating face of the manifold where it bolts to the head. 
Title: Re: Welding manifold?
Post by: Sir Tigger KC on 05 October 2013, 13:58:34
I'd give the High Heat Adhesive a go as it'll be quick, easy and cheap!  :y

As Mark has pointed out it only needs to be gas tight and it's been used and recommended by Symes!!  :y
Title: Re: Welding manifold?
Post by: mrgreen on 06 October 2013, 08:30:42
I'm going to try that adhesive as mine has a crack and although i've got another manifold for it i am too scared of shearing off bolts to replace it!!
Title: Re: Welding manifold?
Post by: Steve B on 06 October 2013, 12:05:31
So do the 2.2 manifolds seem to all crack in the same place  :-\
Title: Re: Welding manifold?
Post by: Marks DTM Calib on 06 October 2013, 19:08:57
If welding it then you need a U prep rather than a V.

For both welding and any other repair method, a small hole should be drilled first at both ends of the crack to stop the crack propagating in the future (a hole has no corners and hence no points where a stress riser can form)
Title: Re: Welding manifold?
Post by: omega3000 on 06 October 2013, 21:08:31
So do the 2.2 manifolds seem to all crack in the same place  :-\

2.0 crack as well . Normally in the middle top or bottom .