Machine the nick in this head? With pic

[larrykjr]

I dropped off my 01 OBW 2.5L w/114k to my (trusted) Subie specialist mechanic for HG's, timing belt, etc and he found some nicks on the gasket surface of the head on the driver's side. Looks like the HG's had been done before and they nicked it somehow. They are fully covered with the gasket when you lay it on there, and the concerning part is that the closest scratch is about 1/16'' from the right combustion ring. It's pretty shallow and he says that you can barely catch it with your fingernail. The deeper one to the left is far enough away that I'm not too worried because it's far from the cylinder and the coolant jacket and this motor has the open deck so the other surface of the gasket is floating. What do you guys think? I'm gonna keep the car and want to do it right but the cheapest best way. About $100 to machine the heads, or buy a used head, or leave it alone?

[Fairtax4me]

You should have the heads machined anyway, being a 2.5. As long as it is outside of the compression ring it should be fine. Any machining to remove the knick will probably mean taking the head thickness below spec. Head specs go by thousandths of an inch. The maximum warpage spec for a cylinder head is 0.005", which is about the width an average human hair.

 

As long as the knick is outside of the compression ring, it should be fine. I would just get it resurfaced, and put it back on.

You might talk to the machinist to see what he thinks about possibly making it better. Making it go away completely would mean machining the head a fair amount though.

[larrykjr]

Fairtax4me, thanks for the quick reply. I think you are right to recommend getting it machined. I don't know anything about how far they can go so maybe I'll ask the machinest to see if he thinks he can get out the smaller nicks. I doubt he can get out the deep one, though.

[johnceggleston]

since you didn't know the gaskets had been done before my guess is you haven't had it since new.

 

question: did the nick in the head contribute to the head gasket failure THIS time?

 

how many miles did this gasket last?

 

how many miles have you had the car?

 

is it worth the risk / expense to get the same number of miles this time?

[subaru360]

You need to resurface it now anyway. The guy doing the work for you used one of those 3m pads on the gasket surface and it's not flat anymore.

[Ricearu]

they may have to be redone because they used fel-pro's. make sure you use subaru dealer Multi Layer Steel gaskets. price is fair and worth it in the long run!