Impreza Heads.....

ScoobieWRX · Post by **ScoobieWRX** » Mon Jul 21, 2008 1:30 pm

The same as there is a sequence to tighten down the cylinder head bolts/nuts on an Impreza cylinder head is it the same for removal of?? Could removal of the nuts/bolts in the wrong order cause cracks??

Cheers

Gerry H · Post by **Gerry H** » Mon Jul 21, 2008 2:16 pm

Yes. You can warp a head by undoing the bolts without consideration to sequence and tightness.

ScoobieWRX · Post by **ScoobieWRX** » Mon Jul 21, 2008 3:30 pm

I've heard of heads warping if the nuts/bolts haven't been undone in the right order but would that cause cracks as well?

And another quick quesation

Are cracked heads a common problem with subaru engines?

Gerry H · Post by **Gerry H** » Mon Jul 21, 2008 3:53 pm

IMO it's unlikely to crack. I have heard of heads suffering cracks at the plug holes iirc.

Have you got crack heads?

neilK · Post by **neilK** » Mon Jul 21, 2008 4:14 pm

Gerry H wrote:IMO it's unlikely to crack. I have heard of heads suffering cracks at the plug holes iirc.

Have you got crack heads?

Mike Paynes Heads were found to be cracked around the plugs when the engine was stripped and rebuilt recently. not sure if this is a common issue though
.

ScoobieWRX · Post by **ScoobieWRX** » Mon Jul 21, 2008 5:51 pm

No crack heads here Gerry......not even a piss head :lol:

Apparently the bloke i sold my engine to, on a for spares or repair basis, reckons that when the heads were taken off (which he did himself) and pressure tested ( at a garage) they found cracks from the spark plug area down which weren't visible from the outside.

I have no idea if this is true or not because the engine was running fine after the big bang and i even drove it into my garage and it was running fine then apart fromt he knocking. It's never ever overheated since i've had it and when i took the engine out there was no oil in the water and vice versa so i assumed the heads were fine. It made good power too so i had no reason to even think the heads were a problem.

It would seem this is a common problem then. Oh well...shit happens!!

stockcar · Post by **stockcar** » Mon Jul 21, 2008 7:18 pm

fine hair lone cracks can often be seen radiating out from the plug holes........unlikely to cause a problem in general use

ScoobieWRX · Post by **ScoobieWRX** » Mon Jul 21, 2008 9:23 pm

Well the chap i sold the engine to said the pressure test didn't show any leaks but because of the cracks the mechanic putting the engine together said he wouldn't guarantee the work therefore wasn't prepared to do the work using those heads.

So the chap rings me and says oi i want some money back off this engine!! I said to him the engine was sold for spares or repair which is as he bought it, told him he knew the heads weren't pressure tested because i told him so and they were still fixed to the engine anyway so how could they be pressure tested :roll: , and he knew i gave no guarantees on anything as it was sold for spares or repair and that's how it was advertised, needing a rebuild.

So i told him to sling his hook and gave the example, if i bought a car for spares or repair and found a thousands things wrong with it, did i expect to get my money back....NO!!, because that's the chance you take when you buy for spares or repair.

The engine wasn't sold knowingly with cracked heads, and as it's not leaking as Alyn has said, under normal useage they would probably be fine to use but clearly this chaps mechanic isn't willing to use them but that is not my problem.