Welding Aluminum Cylinder Head

Hi Everyone,

Well my 93 Pontiac Sunbird gas beater finally took a crap on me. The engine is a 2.0 litre 4 cylinder with an aluminum head. Pulled the head off and came to find out it was cracked in two different spots. I went to the junkyard to find a used head and no luck. A new one costs $400 and I dont think i want to do that considering I paid $600 for the entire car. There are 2 cracks in two different intake ports and they both run down the ports quite a ways. I was just wondering if it is reasonable and effective to try and weld up the cracks? The local mechanic thinks that he can drill out the cracks a little farther so he can lay a nice bead so it will seal up good. Is it difficult to weld on aluminum or is it just like regular welding? I just as well junk it if welding it doesnt work cuz I just cant find it justifiable to buy that new $400 head. Any suggestions? Thank you.

requires a tig weld with aluminum filler material. NOt really that hard to do.

K

Not difficult, but does require a certain amount of skill. Not something your average mechanic is capable of...usually.

Vince

If your mechanci wants to try it, it will probably work. My cousin is a mechanic who has done a few of these, no problems so far.

my dad welded up some aluminum 350 heads for a friend of mine and they worked great after that.

I would find out if the person doing the welding has done this type of job before and also if they are going to use AC or DC Straight.

Also do they perform a pre-heat before starting to weld it.

Tmod

First the head will need to be dis assembled and cleaned before welding. Once the head is welded the repair is only half done. The head should be straightened and reheat treated. After that it will still need to be shaved to get the deck surface completely flat. If you have the job done right it will be cheaper to exchange the head for a rebuilt one.

A dead 93 Sunbird is a throw away car and your 's time has come. But I don't understand why you can't find a good used head, those 2.0 motors have been around a while and are not hard to find. Go cruise any big apartment complex and you will see a couple dead Cavaliers/Sunbirds with expired tags, probably get one for free just to haul it off if you look around a bit.

Actually you just described my cousin's old side business, only he did it with Escorts. Buy dead ones for $150, fix timing belt and head problems, sell for $800-$1000. Worked good in his area, lots of young people without much $$ needing wheels for work.

they need to be heliarc welded.
but my concern is if the cracks are that big youll eventually warp the head real bad by welding them.

We TIG all aluminum head repairs.

Any type of welding on any cylinder head is going to require complete cleaning of the head, pressure checking, and in the case of aluminum, a dye pentrant or zyglow inspection before any repairs are attempted.

The head should be preheated before Tig welding is done. Skill is required, and the repair should be pressure checked again once it's welded. If welding takes place anywhere near seats, then you probably should replace them. Definitely a resurface job from the warp caused by the intense heat and a valve job will be required.

You might keep looking for a good used head, to fix it right will cost you.

I don't know about you guys but $400 for a NEW head doesn't sound bad at all to me. The hassle of fixing an used "up" head just isn't worth the hassle. If the repair is not done right, you will be removing the head again to try to fix it again or to replace it anyway. If the car isn't worth $400 to you maybe you should scrap it and buy something else to drive.

I would not weld a head and bolt it back on. You need to have it machined after the welding and grinding is done. Of course you will have to totally disassemble it as well. While your at it you might as well replace the seals and get a valve job. Unless you have a machine shop in your back yard it's going to cost more to fix that head than it will for a new one.

Royce

Try looking at www.car-part.com
Looks like there are places that want as low as $99 for a cylinder head.