Thread: Is there such a thing as a "soft" head?

Originally Posted by facarroll

Just pulled the head off 200 Tdi and sent it away for skimming and crack testing. The response from the reconditioner was that there are no cracks, but because the motor got hot, the aluminium has become soft, and I should go for a reco head. Has anyone else ever heard of this, because it's new to me. He also says that I shouldn't use a composite gasket. I've already ordered an Elring from UK. Any useful advice. BTW, the gasket hadnt broken, but a straight edge showed warping. Leaking between numbers 2 and 3.

Very common on 300tdis - do a search.

Yes.

They drop a small ball bearing onto the head. If the head is still hard, the ball will bounce quite well nad the head will ring.

If the head is soft, the ball doesn't bounce too well and the sound is more like a soft thud.

See http://www.engineworx.com.au/HardnessTesting.htm

and

http://www.jaeparts.com/gasket.pdf

You may also have luck searching for the term 'porous head'

Soft heads are very common.........couple of fellows at work have them......err.......ahhhh........ engines...Yes....Soft heads on engines...Oh I see.......should read the post better. Similarly soft heads are a common result of cooking ya engine...and the metal swells particularly around the cylinder. The ball bearing in a tube is the best way to tell whether ya got a soft head.....I wonder how they would take to me bounceing ball bearings off their heads.

Originally Posted by RobHay

Soft heads are very common.........couple of fellows at work have them......I wonder how they would take to me bounceing ball bearings off their heads.

As long as the air pressure is high enough they might not complain at all

The ally heads can be re-hardened in many cases, although the cost is somewhat dearer than a new head................ if you can find one.

Common on Ford Falcon sixes. Ford not being big on quality components or quality control. When the cheap crap head gaskets Ford uses as OE fit leak, you generally find the head bolts are stuffed and often the head is too soft to reuse.

Bugger being a 200Tdi, heads are getting hard to find.

I believe you can have the head re-hardened if it isn't porous or cracked but unsure of costs involved and it may be hit and miss in the heat treatment department ?

I've also heard talk that a 300Tdi head may be able to be retrofitted, but unsure of the work involved as anything is doable, it all comes down to cost effectiveness.

BTW, Genuine and aftermarket parts are available from a couple of good suppliers in Sydney at wholesale prices
Karcraft in Silverwater is who I deal with and I've heard good things of BMI at Mulgrave.