Post Mortem Pulling head - what comes off?

[carl johansson]

Ok guys,
So i now have to pull the head and do a post mortem, try to figure out why a new HG - Toyota OEM, would fail after less than 5 hours.

I have no idea, but i did farm out the job to a trusted mechanic - but maybe he made a mistake, so now I need to do it myself!

So to get the head off, what bits and parts come off - specifically in the intakes and manifolds. The FSM is a bit unclear at least to me, so on the exhaust side - would you pull off the header from the head? or disconnect it at the collector? or both?

As for the intake - would you take that off in 2 parts, or the whole thing at once? I assume you have to pull off the 1st part. over the top of the head, to get at the head bolts, but what about the part that wraps around the side of the head? pull it as one - or seperately? - what works best!

Carl "clueless in Fresno" Johansson

[cre]

Hey Carl,

With the GE I always unbolted the exhaust at the head, disconnected the exhaust hangers and swung it aside. With the intake I usually leave the intake in the car but I think it's easiest to disconnect the lower half from the head with the upper half disconnected first... I can't recall if you can even get the lower half off without first removing the upper.

As for what could have gone wrong... A lot of things, really. The first could things I would check for are significantly distorted jackets in the head gasket, pitting (especially if it's close to the ring lands), warpage. Was this a composite or MLS HG?