Welding K1100 Cylinder Head

[Popcorn]

I'm about to weld one of the above heads, wanted so pointers as I've not attempted anything like this before.
@Brad93 you've already told me what type of filler to use 4943, I've now acquired these. I'm dry decking the cylinder head ie. filling all the water ways and oil ways including the 2 at the back of the head, the holes I've circled in the pic and the 3 small round holes between the chambers, I'm know I need to pre heat the head, to what temp should I be aiming for, I've seen 150 degrees C quoted on similar projects is this enough ? I'm planning on using a gas heater and hot air gun to do the pre heating.
Welder is a R_Tech 201 and as mentioned the filler will be 4943 which I have in 2.4mm. What sort of settings should I be starting with ?

 

[Fazerruss]

I'm curious, what is the reason for "dry decking" ? How will the head be cooled? Its something I've never heard of. Are you wanting to fill the holes completely or just cap them off? I presume you will be having the head skimmed afterwards?
Looks like it needs some serious cleaning before you near it with TIG torch.

 

[Popcorn]

It's going on a BMC A series engine (mini), it's getting to be quite a common conversion.
You can get away without dry decking the head but that means using a very expensive gasket.
The heads looking a lot cleaner now I'm about half way through cleaning it, just not got a very good picture due to the glare of the shiny alloy.
Yep the head will be skimmed after welding.

 

[Popcorn]

Here's what I'm aiming for:

 

[tom2207]

Ive heard lots about this conversion , and will look forwards to hearing about your progress , and the end results.

 

[minimutly]

Here's what I'm aiming for:

View attachment 238460

I have an 8 valve head waiting for this conversion - please let us all know how you're getting on. All I've done so far is machine the cam pulley cover off.

Re the welding of the head - you need a water cooled torch, otherwise it will take you forever. Should you clean the waterways, make ally plugs, bang them in and weld around?
Also, now I'm not sure what grade of ally these heads are made of, but generally I've found that when they get really hot (say due to gasket failure), the metal softens considerably, making it difficult to skim cleanly. So maybe slowly slowly (or rather quickly for each weld then allow to cool?) is the best way to go?

 

[Popcorn]

Cheers minimutly it's all in hand including water cooled torch, got some alloy for the plugs. My understanding is the only plugs made are for the 2 oil returns at the back of the head.

 

[tom2207]

would it be worth cutting up an old head to make your own plugs , fill in the bulk of the hole to start with ... just a thought. at least the alloy would match maybe not enough room for that after looking at the pics.

 

[WorkshopChris]

Should you clean the waterways, make ally plugs, bang them in and weld around?

Would that promote cracking around the weld area as the plugs and head would expand and contract at differing rates in everyday use?

 

[minimutly]

No, don't see why, you would use similar metals, so long as you didn't use extreme force to push them in - in fact they wouldn't need to be a press fit anyway.

 

[minimutly]

Here's what I'm aiming for:

View attachment 238460

Those inlet valves look huge in there @Popcorn , what sizes are they? Be nice to compare them to the 8 valve, and also other 16v heads.

 

[ronan]

Any of the American guys i have seen welding aluminium castings (Motorcycle bits usually) online, say they pre-heat to 200 F, which is 95 ish degrees celcius. I think the idea to plug the larger holes is a good one rather than trying to keep filling around the edges. Sometimes you can over think things and you just have to get on and try do the job the best you can.

This is a conversion i heard about years ago, its interesting, hope it works out for you.

 

[cheb]

If you block off all the coolant and oilways how is the head cooled and lubricated? I must have missed something blindingly obvious.

 

[ScoobyMick]

If you block off all the coolant and oilways how is the head cooled and lubricated? I must have missed something blindingly obvious.

Re-drilled to suit the A series block ?

 

[Popcorn]

Those inlet valves look huge in there @Popcorn , what sizes are they? Be nice to compare them to the 8 valve, and also other 16v heads.

It's just a photo I grabbed of the net bud, don't know who's head it is. Get over to 'Turbominis' forum lots of info there on this conversion, not a lot of detail on the actual welding though, that's why I thought I'd ask here.

 

[Popcorn]

If you block off all the coolant and oilways how is the head cooled and lubricated? I must have missed something blindingly obvious.

You weld a pipe onto the side of the head and bolt another onto the block using one of the core plugs. The oil feed is taken from the oil pressure pipe feed on the front of the block, you need to remove a Allen screw from the head and drill and tap it for the 1/8 NPT fitting.
The bloke who first di this conversion has website covering that first one it's here:
http://www.lojomo.com

 

[Steveblade]

If you get it clean its clearly viable to weld up the holes, I think you will struggle with that machine though, you could do with more power on tap. I hear ( never tried) helium added to the shielding gas helps get more heat transfer into the work but thats a big chunk to weld, your going to have to get it very toasty to weld with less than 250 plus amps. Its effectivley a big heat sink

 

[ronan]

If you get it clean its clearly viable to weld up the holes, I think you will struggle with that machine though, you could do with more power on tap. I hear ( never tried) helium added to the shielding gas helps get more heat transfer into the work but thats a big chunk to weld, your going to have to get it very toasty to weld with less than 250 plus amps. Its effectivley a big heat sink

Helium does work, and you can weld aluminium with DC rather than AC too, but go onto BOC and look at the price ! Warning, you'll need a couch to flop on and some tissues for your nosebleed when you see the price.

 

[Steveblade]

Yeah I hear its pricey, another bottle rented forever to cus you aint going to waste the stuff. Maybe just hire a bigger machine. Electricity is cheap by comparison.

 

[minimutly]

You weld a pipe onto the side of the head and bolt another onto the block using one of the core plugs. The oil feed is taken from the oil pressure pipe feed on the front of the block, you need to remove a Allen screw from the head and drill and tap it for the 1/8 NPT fitting.
The bloke who first di this conversion has website covering that first one it's here:
http://www.lojomo.com

Always arguments who was first with anything, I remember seeing it first in "fast car" or "ccc". Some french I think student did it, no idea when, but I think pre '89. I probably still have the mag in the loft, please excuse me if I don't go looking for it....