Welding iron head

[mag2555]

Hi all!
Any one have any suggestions as to how or who might have success in welding a iron head where cutting it for intake seats has made pin holes into the water jacket?

Note that now there is sealer inside these heads so I do not know how that might effect welding them.

Also one other question if I might, how thick does a water jacket wall need to be to try to stitch these up?

Thanks in advance.

[1980RS]

The only thing I have found that works for me is Muggy Weld rod. Fixed 2 blocks and 2 heads with the stuff so far. I always try to weld cast iron on the hottest days as even though I have had good luck with this stuff it's still better to cool the cast down slow. I have also heard Crown cast iron welding wire in a mig welder works too.

[HQM383]

Nickel electrodes for stick welding or nickel or nickel/bronze for brazing. A bit more control with the brazing. Heat the entire head until you can barely touch it - that will be around 50c (122f). Do the welding and then throw a heat proof blanket over and let cool.

[Tom68]

I wouldn't weld in this situation, unless it's a boat cooling with lake water and not exposed to combustion chamber pressure, I'd put a can of Wynn's radiator stop leak in.

I only recommend that brand because it's saved my arse several times over the last 35 years, other brands will no doubt work.

Wouldn't weld because cracking afterwards is highly likely, I have a set of Iron heads that had intake seats cut for inserts that went through to cooling in every port for several square mm each, big wide cuts allowed you to look into the coolant passages. Machinist fitted inserts with JB Weld or some other unlikely to work in this situation on my daily driver. After a year or so it would start up on maybe 5 cylinders and progressively work it's way up top 8 over a couple of minutes. One morning I started it, normal 5 cylinders firing, turned it off, pulled the plugs, probably pulled 4 out , found water droplets bridging the gaps on a couple, put a can of stop leak in every year for several years until the several hundred thousand mile cam finally run a lobe, never had a misfire after the stop leak.

P.S. These old Chevy heads had the bits of stainless steel looking weld on he rocker cover rails that I've seen on a few old heads. They're still bolted onto a 307 25 years after parking it, maybe I should pull them tonight for pics ? Oh yer, they've been through a flood as well whilst in storage

[Tom68]

Nickel electrodes for stick welding or nickel or nickel/bronze for brazing. A bit more control with the brazing. Heat the entire head until you can barely touch it - that will be around 50c (122f). Do the welding and then throw a heat proof blanket over and let cool.

Oh.....you do know your stuff then. I was reluctant to suggest it, but yep, Nickel alloys are the best option and this is definitely a braze not a weld situation.

[Tom68]

LP Gas through the primaries with these heads so heavy exh recession.

These are the heads with intake seats broken through to coolant.

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[rebelrouser]

Been messing with engines since 1974, I have seen a lot more grief than success when welding cast iron. Yes I know it can be done successfully, but at least in my area, welders that can pull it off are few and far between. What I have seen is the issue of stress in the cast iron after welding always leading to cracks down the road. I taught at a technical college and the welding instructor there simply said if you cannot properly pre heat and cool down the iron after welding it simply will not work. That shop had an oven which would hold a cylinder head or block. I have seen guys use a BBQ grill for heating and cooling. My bottom line is how much time and money will be lost if the weld fails compared to simply buying a different set of heads, either new or used.

[jcisworthy]

Seat pocket is a tough spot to weld successfully. After welding you have an interrupted cut on a hard material and its no fun plus it usually fails.

I have successfully drilled out the hole to a larger size, threaded it not all the way through with the tap, installed brass set screws rough cutting most of the set screw back then cleaning the hole with the seat pocket cutter. Basically small diameter stitching.

Note, I said not to run the tap all the way through assuming there will be and air pocket behind it. This allows the set screw to tighten up and lock in whereas if you tap all the way the screw will be somewhat loose.

Good luck, it's hit or miss

[learner1]

https://cast-iron-repair-specialists.bu ... m=referral

He's the best

[vortecpro]

You need this done-no problem.

[T-flow]

I had some welded up years ago, pin holes on the deck. Stainless wire, preheat the head tig welded.

[HQM383]

I had some welded up years ago, pin holes on the deck. Stainless wire, preheat the head tig welded.

Yep. ER309LSi filler rod.

[6sally6]

Can you drill a hole at the end of the crack to STOP IT from continuing to spread?

I would drill hole(s) at end of crack
Clean it with wire wheel/acetone
Grind a shallow groove along the crack
Using a rosebud...bring temp up to minimum of 250* along big area of the crack.
As soon as its 250*+ start welding crack. (weld it hot to get good penatration)
Peen over weld area with needle gun to help relieve stress(The iron & YOURS!)
Reheat whole area to get the temp up to 250*(if it has fallen)
Wrap in a fiberglass blanket to SLOOOOOWLY cool it down.
Maybe...ever so often use the rosebud to slow the cooling process.
Re-wrap with the blanket after warming.
Several hours of controlled cooling will increase your odds of no crack(s)
6sally6

[vortecpro]

No pin holes here.

[econo racer]

Would it just be easier to find another head?