jdmarsh

I recently got a 3 angle valve job on a b16 head and when i was preping it to go on my block i noticed small cracks on the valve seats. When I took it up to the machine shop they said that it is a common thing with these heads and to not worry about the cracks and that they wont hurt anything. The machine shop is Houston Engine & Balancing and they do really good work. Should I take their word on it? Does anybody else have this on their head.

Mach1n1st

It's a very common problem on Subaru heads and on boosted cars it is caused from a number of things one of the more common is excessive timing I see this stuff all the time in a factory rebuild that will not get beat on it's ok..... I say that loosely cause I don't trust it but lots of people still run the head with no problems and I've seen a set of suby heads make 500whp on a set of heads that were cracked just like yours personaly when I find issues like this I stop and call the coustomer and see if they want to continue with the work or find a new core I think that's what the machine shop should have done in this case

EG1834

I find it hard the believe that cracks around the valve seats are okay.

DDTECH

jdmarsh

Thanks for all the inputs. Anybody else seen this?

kingofbattle909

iTrader: (6)

I have a hard time believing they're a good machine shop. They messed it up and lied to you!
NO. IT IS NOT OKAY. aND They should pay for it.

hybrid_KJ

If the machine shop only ground angles into the existing seats and did not change out the seats then they did not cause that. Wether or not it is ok to run is another story. They probably should have identified the cracks and then contacted you about wether or not you wanted to have the head machined. I have seen those same kind of crakcs beofre and they are very hard to see before the head is cleaned/media blasted.

Rosko

iTrader: (1)

Is it the valve seat or the casting around it thats cracked? The aluminum is very thin there, I'm sure its more common than you would think. Some of these heads have had a long life.

kingofbattle909

iTrader: (6)

x2

MAX_CFM

it is very common

I see my share of that .. I see 30 heads a year that look like that ..

to fix that you would have to weld up the crack after you grind it out and replace the seat

.. I have seen big power from heads cracked liked this ...

900 plus with no problems .. when they crack into the Spark plug the seat does not loose

press like you would think ...


anyways Im sure im wrong about this .. so flame away

jdmarsh

Thanks for your input. The machine shop said I shouldn't waste my money on a new head because it could most likely have the same problem. I was debating on whether or not I should use it. It's not a daily so I will run it and if it gives me problems I will update this Forum.

Thanks

dntnedvtec

If it looks broken, it probably is. If it looks cracked, and its not suppose to be cracked, hrm.....

kingofbattle909

iTrader: (6)

<(--went into a apple store today, started swingin' around a 9 Iron-
it seems i cracked one of their new Ipads.
=meh..
"they've been known crack from time to time"