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Panko

Cast iron manifold needing repairs

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Hi guys, i have a cast iron turbo manifold for a cross flow, stamped 1981. However i today test fitted it to my head, and turns out its slightly bent, believe it or not. So cyclinders 456 all line up ok, but 1&2 i cant get bolts into, and 3 i can only get one bolt in. Is this able to be repaired? If so can anyone recomend a place around melbourne who can.

 

It also, has a slight crack (see photo below) that i need to get sorted. Again if repairable where ?

6D36793C-A5E8-4CC1-B1D5-1803AD191422_zps

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Hi guys, i have a cast iron turbo manifold for a cross flow, stamped 1981. However i today test fitted it to my head, and turns out its slightly bent, believe it or not. So cyclinders 456 all line up ok, but 1&2 i cant get bolts into, and 3 i can only get one bolt in. Is this able to be repaired? If so can anyone recomend a place around melbourne who can.

 

It also, has a slight crack (see photo below) that i need to get sorted. Again if repairable where ?

 

 

Everything can be fixed . just depends on how much you want to spend, by the sounds of things, it would be cheaper to get a new one made from steampipe, than to have an engineering shop fix it 

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Looks like that thing's been pretty hot. You could hacksaw the bent runners off and weld them back on in the right spot using an electric brazing rod or nickel one suitable for cast iron repair. Pre-heating is a must. Here's an engine build on a Ford 300 six where they broke part of the bellhousing face off and welded it (mind the ads, they get quite annoying):

 

http://www.powernationtv.com/episode/EP2014-04/hopping-up-an-old-skool-six-part-2

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Depending how much it is actually bent and twisted it may not be repairable. Cast Iron can be worked and moved back into shape but not very much and it must be done by people that know exactly what they are doing. It needs to be heated to red in colour then pulled back into position very gently. This is no guarantee that it won't crack either and I would be cautious on anyone that claims they can fix it no drama unless they have a long history of working with cast iron.

The next and what I would think it the biggest drama is the pic you have taken. 100% agree with Greg that the manifold has gotten very hot, but I would want to know what actually caused that major crack as it goes all the way down the centre piece and it has been bent, cast iron does not bend very easily it just normally cracks and I can't see an impact mark on the divider. There are other cracks in the flange other than the major one, I can see a definite 1 and possible 2 more and trying to get a good weld with full penetration with distortion and maintaining a square face will be a challenge. Lastly I don't know if its the pic but it looks like the flange has a hollow in it on the right hand side between the studs in the flange which will affect the turbo to flange seal.

 

If this needs to be repaired to keep the car period correct then chose your repairer very carefully and I would not be restricting your search for a tradesman to your local area, you may need to send it away to be repaired.  The other option is to take the cast manifold to someone to copy and make a new one out of steam pipe as suggested above. Steam pipe is just thick wall mild steel pipe like 3.5mm wall on a 50mm outside diameter pipe (triple the thickness of regular exhaust pipe) Buying steam pipe is not hard at all, it is known as buttweld joints and comes in different degrees and lengths of bend and its relatively cheap. You will still need a good shop to be able to copy the cast manifold but that is more of just getting a quality job done. You could also use stainless pipe but Im not a fan of that as even na exhaust can crack due to heat cycles so a turbo it will be a worse.

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Run a drill thru the holes so you can get your bolts in and machine the face flat so it seals on the head face

The manifold is just split pulse manifold does it even matter its cracked? just machine the face of it as well and go again if its not leaking. I have a cast manifold on turbo corty I think there rubbish, id just make a log for it cheap as and if it shits itself make another one

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thanks guys for the answers. 

Dave i will need to look at it again as to whether i have enough material to drill the holes out any further. it has multifit flanges on it, by the looks to fit a 4L OHC engine as well (strange) 

 

the engine its going on is only running low boost for now, so if i can make it work, im happy with that. perhaps in the future i look at getting it replicated. 

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multifit will be for cast iron head. i'd also just do the machining of the mating faces and file out the mounting holes till they fit.

people have used a J pipe off the stock manifold with success so any manifold is probably better than that.

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multifit will be for cast iron head. i'd also just do the machining of the mating faces and file out the mounting holes till they fit.

people have used a J pipe off the stock manifold with success so any manifold is probably better than that.

 

Gary used a standed manifold on his old XF Ghia turbo (WYLDXF) never seemed to have an issue.

 

Another way of truing up the mating surfaces is to use a belt sander, keeping the flanges flat of course and checking as you go.

 

Be sure to check the mating surfaces with a straight edge Aaron :)

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Just be careful when facing the flange, measure how much needs to be removed before going ahead. Cast iron is strong but requires meat to retain strength, if to much meat is removed it will crack easier. Also you will need to control the heat when facing as if one part gets hot and the heat travels because another area is cold thats when you will get cracking as well. NEVER quench it to cool it, it must be placed on something that wont suck the heat out to fast otherwise it will crack. Yes cast iron can crack quite easy if you don't take care

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Looks like that thing's been pretty hot. You could hacksaw the bent runners off and weld them back on in the right spot using an electric brazing rod or nickel one suitable for cast iron repair. Pre-heating is a must. Here's an engine build on a Ford 300 six where they broke part of the bellhousing face off and welded it (mind the ads, they get quite annoying):

 

http://www.powernationtv.com/episode/EP2014-04/hopping-up-an-old-skool-six-part-2

 

Great video, use ad blocker. I watched a few episodes with no ads what so ever! :)

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Not sure why people don't think these manifolds are any good. People have made good numbers with them. Pretty hard to make a log manifold that is any better.

 

As said, that crack doesn't matter, but would be easily fixed with castcraft rods in an arc welder. They often crack there, but I have never seen an open crack like that (usually hairline).

 

Bolt holes on them seem to be close not to fitting at the best of times. I'd be following pro250's advice here.

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To much talking that manifold would be fixed now if it was mine and matt would have done the welding LOL well if adam was not at home

are we at the maching shop machineing it yet panko? boost it common :D

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