Just curious: anyone else seen lots of head-cracking on the little GM pickups with the 5-cylinder engine? Around our 'lil town, both Chev and GMC's are cracking them. Valves seem to be ok, and they are replacing with new heads and old valves--salvage yards, I understand can't get/keep them. sdlomi2
I haven't seen any of that in the dealership...but we haven't had any super high milers yet. I'd want to see what people are calling "cracks". There have been any number of cylinder heads over the years that will develop small hairline cracks between the two valves. Most of the time, it's totally normal and will not affect the engine. But a lot of places would instantly sell the customer a reman cylinder head.
A lot depends on who is looking at the cylinder heads.
Ian
So why would anybody have the cylinder head off if there wasn't some sort of problem?
Ed
Valves or seats needing work, would be my guess. I can remember some V8 heads are known for cracking between the valves. Whether or not the head has to be replaced is another matter.
Good question! I'd be interested in finding out what these heads are being pulled for.
Ian
Some may be for overheating, but iirc most are due to skipping due to low compression. s
Hmmmm....not quite sure what you are saying here. There was/is some problems with the 5 cylinder engines, the fix is to replace the valve springs. I wonder if shops that are unaware of this problem are pulling heads in order to try to repair this problem.....? In some cases, the cylinder head does have to be replaced, but it's not due to "cracking" of the head.
The bulletin number that refers to replacing the exhaust valve springs is #04-06-04-081C
Ian
C'mon, Ian.. You know what is going on. Some of these American dealerships will hump you with all the market will bear. Whether it is the fix, or not.
Was he talking about dealerships? I didn't get that from the post. I know for certain that we wouldn't do anything like that. Nobody really "wants" to pull the heads off these engines if they can avoid it.
Ian
I misspoke, Ian.
Not just dealerships, but some unscrupulous shops would also do this.
And, in retrospect, if they open the engine for compression issues and see cracks maybe they would be foolish not to 'fix' what they perceive as a problem.
I am sure your dealership shop would handle this professionally.
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