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jblen536
09-14-2007, 05:50 PM
We have a 2002 XSTAR with a 350 Chevy engine; With only 600 odd hours on it, two of the valves in the head leaked by. The mechanic who made the repair said the head was defective from the manufacturer (ie: was cast 'thin' in the areas where failure occurred) Just wondering if anyone else has had this problem.

east tx skier
09-14-2007, 06:02 PM
I haven't read about anyone with defective heads. You might also try asking on a Chevy truck forum though. Not that someone hear might not have had the problem, but just by volume, if it was a common problem, you might have a better chance of finding more of them.

Maristar210
09-14-2007, 10:54 PM
We have a 2002 XSTAR with a 350 Chevy engine; With only 600 odd hours on it, two of the valves in the head leaked by. The mechanic who made the repair said the head was defective from the manufacturer (ie: was cast 'thin' in the areas where failure occurred) Just wondering if anyone else has had this problem.


Never hear of this. Sounds like Bull **** to me

T-Rager
09-14-2007, 11:26 PM
We have a 2002 XSTAR with a 350 Chevy engine; With only 600 odd hours on it, two of the valves in the head leaked by. The mechanic who made the repair said the head was defective from the manufacturer (ie: was cast 'thin' in the areas where failure occurred) Just wondering if anyone else has had this problem.

What exactly do you mean by "leaked by"? Was there a compression problem, a coolant-leaking problem, or an oil-loss problem? I'm not familiar with your terminology. Please explain.

JimN
09-14-2007, 11:35 PM
'Leaked by' almost sounds like they tulipped and bypassed the valve seats, which also sounds like water got into the cylinders and if it had stopped, would have hydro-locked. Thin castings? WTH? If he didn't replace the heads, how did he repair it? If it's a cast iron 350, I seriously doubt this diagnosis. GM has made literally millions of these motors and unless someone was PO'd at GM, they wouldn't have made it past inspection. Valve seats aren't just machined into the heads, they're a different material and are pressed in.

I hope someone can give a good definition of 'leaked by'. If the valves burned, it sounds more like it ran lean but that could also have burned holes in the pistons.

pilot02
09-15-2007, 01:34 AM
"Leaked by??" I second JimN's response.. There's slim to no chance the valve would leak around the seat. Through the seat, yes if there was a poor valve job, carbon build up or a bent valve but not around. I don't buy it.
And if your mechanic was able to repair this "leak" without welding the head, completely remachining the area where the seat is pressed in, I definitely find his diagnosis and repair techniques doubtful at best.

pilot02
09-15-2007, 01:37 AM
Second comment. Did you retrieve this "defective head?" because I'd sure like to see a reputable machine shops review of this one...