Cast Iron Cylinder Head

[doubleboost]

I have been asked to weld this
I was thinking of milling the crack out then
Preheat 100 deg C (just to take the chill from it)

use Aluminium Bronze filler wire (TIG Braze)
The main crack goes between 2 water passages
The hole in the middle is a head stud hole
I could do with buying a few filler rods as a pack is a fortune

 

[Richard.]

Silicon bronze would be my choice for cast iron John.
Do you want a couple sending out

 

[doubleboost]

Silicon bronze would be my choice for cast iron John.
Do you want a couple sending out

That would be good
Would you use A/C with a high EN balance
Or straight DC
Personally i would just leave the crack
But he insists on having it "welded"

 

[Richard.]

That would be good
Would you use A/C with a high EN balance
Or straight DC
Personally i would just leave the crack
But he insists on having it "welded"

Dc with silicon bronze on cast iron works very nicely. Don’t let it puddle. About 50 amps get an arc going and dump in the rod. Do a bit at a time just let the rod melt under the arc and drop into your milled slot.

 

[Brad93]

I’d be tempted to do that with nickel due to the expansion

 

[ronan]

There is a name for jobs like that...................nightmares.

 

[addjunkie]

Belzona 111. Grind it out with a dremel or similar, you might want to drill the top end in the picture of the crack to stop it growing.

 

[decca]

It'll make a good video but!!

 

[Richard.]

I’d actually go with johns approach on this one and mill a small track for the fill to sit in. And like johns thinking in this case I would braze it. A gas braze would be even better for keeping dilution and heat out of the head all together. A nickel consumable would be perfect for welding it as brad said and if that was required to be a decent strong joint then it would be the best approach but once you go down the “welding” route with cast iron you are spinning the roulette wheel. You then need to really watch your temperature and stress releive. That is a big lump so welding would be more practical done cold. It could work and if john decides to do this I can hook him up with some Ni/Fe wire for that too. You’ll likely get pours come through from the casting mind and it might crack again it might not.
I think personally as all we are doing here is filling a gap a tig/gas braze is gonna be the method I’d adopt. As it’s pretty risk free if you keep the arc for melting the filler only.

 

[Brad93]

I’d actually go with johns approach on this one and mill a small track for the fill to sit in. And like johns thinking in this case I would braze it. A gas braze would be even better for keeping dilution and heat out of the head all together. A nickel consumable would be perfect for welding it as brad said and if that was required to be a decent strong joint then it would be the best approach but once you go down the “welding” route with cast iron you are spinning the roulette wheel. You then need to really watch your temperature and stress releive. That is a big lump so welding would be more practical done cold. It could work and if john decides to do this I can hook him up with some Ni/Fe wire for that too. You’ll likely get pours come through from the casting mind and it might crack again it might not.
I think personally as all we are doing here is filling a gap a tig/gas braze is gonna be the method I’d adopt. As it’s pretty risk free if you keep the arc for melting the filler only.

Do you think the CuSi will hold up to the different expansion rates being where it is, between the water ways?

 

[Richard.]

Do you think the CuSi will hold up to the different expansion rates being where it is, between the water ways?

I don’t think on the water ways there is going to much as it shouldn’t elevate in temperature there too much
I’ve not done one before but logic tells me that the head shouldn’t expand much at all. Head gaskets are often steel which doesn’t have much give. If it was a part likely to go through some excessive expansion/contraction then I’d say steel gaskets would likely not seal over time. That’s my thinking mind but I could be wrong

 

[Bill Edwards]

Tig braze seems a useful process which may be brilliant for this type of work, but I have no knowledge or experience of it.

What certainly does work for these is welding it cold using stick and good quality rods for cast (high nickel content). Not the type that welds cast to steel.

It’s got to be kept cool and the weld has to be peened throughout which makes it tedious, but it certainly works.

 

[TechnicAl]

Im assuming they are waterways? If so does it really need welding...they are connected anyway......If so I would leave it alone, theres every chance that heating it will cause more damage.

 

[Kayos]

Im assuming they are waterways? If so does it really need welding...they are connected anyway......If so I would leave it alone, theres every chance that heating it will cause more damage.

That was my thought, especially if it’s rare or expensive enough to not just replace it

 

[dannyp]

my rule with cracks in cylinder heads, unless its the reason the heads been taken off..... what crack i cant see no crack, between

had it with an engine i know recently it has one hell of a crack between cyls 2 & 3, it was there when i rebuilt itquite a few years ago apparently it was there when it was rebuilt meany years before that, motor ran for 10's of thousands of hours like that no problems, guy who just rebuilt it insisted on haveing the crack welded up. now it drinks water and hydrolocks if left overnight