1HDT head (1 Viewer)

[dscawilson]

Wondering how many people have had a cracked head? I'm about to pull the head to replace the gasket. I spoke to a reputable machine shop about getting the head pressure tested and they said its doubtful that it's cracked as its Iron and not aluminum. Just hoping to avoid pulling the cam off if I can.

 

[GTSSportCoupe]

Wondering how many people have had a cracked head? I'm about to pull the head to replace the gasket. I spoke to a reputable machine shop about getting the head pressure tested and they said its doubtful that it's cracked as its Iron and not aluminum. Just hoping to avoid pulling the cam off if I can.

I don't think it's that common on the 1HDT; although not unheard-of. It is definitely more common for the 1HDT head gaskets to leak though. So that is the most likely scenario for you.

The big advantage for the 1HDT is it's direct injection. This means the head is much stronger and sees less heat than say the indirect injection 1HZ.

 

[rick_d]

I pulled a head that was magifluxed and found to be cracked. It does happen. Since the head is off are you going to service it? If so, new valve seals and ideally new valves are not that expensive from overseas. Know your head gasket rules, #2 and #4 are not available beyond the Toyota assembly line and you must upsize one step (If you have a #4, use a #5).