Pistons and rings being replaced, dealer doesn't want to hone.
#21
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I read the GM bulletin on fixing piston slap a few months ago. I was surprised to learn that they recommend replacing the top ring only - no honing is done. If I were GM I would recall every last engine and replace them all. This is a serious factory defect.
Obviously, the bulletin states that the same pistons must be replaced in the old bores...
I would have thought that if the bores were out-of-round that GM would have installed a brand new fresh engine under warranty.
Hey, if the rings don't seal I would bet GM will just replace the engine....
As you should know by know, GM cars are crap - just look at the resale. Some of the decisions on warranty or replacement are dicktated by performance. GM is really sucking wind right now - see the wall street journal article today. I'll bet they would have replaced the engine but since they have not been selling any new cars lately, you get the crappy rebuild instead.
Next time buy a Honda.
Obviously, the bulletin states that the same pistons must be replaced in the old bores...
I would have thought that if the bores were out-of-round that GM would have installed a brand new fresh engine under warranty.
Hey, if the rings don't seal I would bet GM will just replace the engine....
As you should know by know, GM cars are crap - just look at the resale. Some of the decisions on warranty or replacement are dicktated by performance. GM is really sucking wind right now - see the wall street journal article today. I'll bet they would have replaced the engine but since they have not been selling any new cars lately, you get the crappy rebuild instead.
Next time buy a Honda.
#23
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Originally Posted by BBQLS1
Mains are usually between .0015 and .003. and it does make a difference. That's why you see so many people on this site saying a "broken in" car runs quicker than an "off the lot" car. Bearing tolerances get looser and rings seat better.
#24
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Originally Posted by technical
But how does that translate to setting the motor up "loose" like you were talking about? Sure engines make more power after they break in, but we weren't talking about that.
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Sorry, maybe I'm being too thick. I understand how things break-in. What I'm asking is how can you setup a motor loose? You have to stay within the tolerances. By loose are you just saying the loose "side" of the tolerance?
#28
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Originally Posted by technical
Sorry, maybe I'm being too thick. I understand how things break-in. What I'm asking is how can you setup a motor loose? You have to stay within the tolerances. By loose are you just saying the loose "side" of the tolerance?
#29
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If you want to learn a great deal about this kind of stuff, check out Pro Stock racing or Stock Eliminator. These guys are super hard core when it comes to this stuff. Stock Eliminator cars will even run the oil pan dry if they don't shut down after the quarter mile to keep windage down. Hardcore! You can run your oil on the lowside of the dipstick and pick up some power especially if you are running some rpm's. I wouldn't do it on a street car though. I don't think I am that hardcore!
#30
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Like I asked before. What does blueprinting and trickery have to do with a motor built at the factory? FWIW, I'm well aware of the things race engine builders do to achieve the competitive edge. But I don't build race engines so that information is trivial at best. If I ever setup a customer's engine outside of the tolerances, then I just bought an engine and lost a customer.
The original poster is asking about honing his *street* car's engine. He is not in the market for a balanced and blueprinted race engine that has to be shutdown every 1/4 mile to avoid being genaded.
The original poster is asking about honing his *street* car's engine. He is not in the market for a balanced and blueprinted race engine that has to be shutdown every 1/4 mile to avoid being genaded.
#31
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Originally Posted by Spellbound
I am having my pistons replaced do to excessive piston slap by my local dealer. They sent the pistons out to have the rods/pins pressed in and when they came back they did not put them in the order the dealer sent them out in, so they could not reuse the rings. Now they want to put new rings in but they don’t want to resurface/hone the cylinder bores. They said with the molly rings you don’t need to hone and the most important thing is that the cylinders are straight. The dealer said that the engine still had a good cross hatch finish on it and I shouldn’t worry. What do you guys think?
#35
damn this is scaring me outta wanting to get a forged shortblock... all these problems honing or not honing.. and depending on what kid.. like eagle or lunati u have to have it honed by a machine shop or osmething no?
#36
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Originally Posted by redrocketls1
damn this is scaring me outta wanting to get a forged shortblock... all these problems honing or not honing.. and depending on what kid.. like eagle or lunati u have to have it honed by a machine shop or osmething no?