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Originally Posted by drumminforev
So my piston rings are bad, 10 10 15 and 30 are my leakage % based on numerous leak down test. and i burn about 2 quarts a week.
so my question to you is...
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You don't mention what the mileage is on your engine but anything that eats, (doesn't leak) 2 quarts of oil a week, is in serious need of a rebuild.
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Originally Posted by drumminforev
Is it neccessary to buy 0.25 overbore and get the pistons matched to bore...or would stock pistons seat properly with new rings and re-hone?
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Again, if I was to guess, I'd say your engine is high mileage. If your rings are that bad that it's eating 2 quarts of oil a week, I would also be willing to bet that the cylinder walls are worn/scratched enough that you'll require an over bore to get the pistons/rings to seal properly. I'm sure if you simply re-honed/deglazed the cylinders and put the old pistons back in with new rings, it would work and would show decent numbers initially. It is over time that the engine performance would fall and oil consumption would again be a problem. How much time? hard to predict without actually seeing how bad the engine is for myself. In my own personal experience, I've seen the rings not seat at all right off the bat and get blow-by, other times I've seen them seat relatively well for about a year before the problems start to return. This is why I said to just have the engine bored and put in oversize pistons/rings...do it right once and then never have to worry about it again.
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Originally Posted by drumminforev
What is the difference between deglazing with a dingleberry and re-honing with a stone
What is this "glaze"
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ok, first of all, "glazing" is when the surface of the metal becomes "polished smooth" from all the friction. This happens to brake rotors and clutch flywheels all the time and it is why they should be resurfaced/deglazed before installing new brake pads or clutches. Just because a person can see the original factory "cross hatch scuffing/honing" doesn't mean that it doesn't need honing. You can still see the tread pattern on a tire that's 80% worn but it doesn't mean it's going to grip like it's supposed to. When the metal is glazed it doesn't create proper friction with the new surface that is going to be in contact with it and therefore it doesn't "wear in" together properly. Try thinking of it like putting your "brand new" feet into someone else's shoes...they'll eventually adjust to YOUR feet but never as well as a new pair of shoes would.
As for the dingleberry vs. using a stone hone, I'll have to give you my personal opinion on the two. To me, the dingleberry is ok to use as long as the cylinders are in good shape with no deep scratches, the engine isn't high mileage and the cylinders just need a little "scuff" before reinstalling the original pistons and/or new rings. To me it's similar in concept to using a 3M "scuff pad" on your brake rotors or flywheel before installing the new parts. It is far better than putting everything together this way than doing nothing at all. The stone hone does more actual honing in my mind as it deglazes the cylinders and will take out some light scratches in the cylinder walls and creates more of a factory "cross hatch" type of scuff into the bores. Again this should only be done if the cylinder bores are in good shape, if in doubt, have it checked and bored. Either way, you have to be careful using either of these methods since more damage can occur if you don't know what you're doing.
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Originally Posted by drumminforev
What is the name of the tool that measures bore, where can it be bought.
What are the spec tolerances for a b16a2
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It's morning and my brain isn't fully functional yet so I can't remember the specific names or specs other than the fact that most people use a dial gage and/or caliper combination to measure bore specs. These tools should be available at any automotive tool stores that sell specialized tools. As for the spec/tolerances, I would grab a Helms manual which would give you the specs and the names of the tools you are asking about as well as how to check the specs.
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Originally Posted by drumminforev
What is lapping.
How do i know if piston rings are lapped, and how do i lap them.
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I'm not entirely sure what you're asking since "lapping" is somewhat of a general term and is mostly used to describe a process you do to intake and exhaust valves. The only thing I'm familiar with is gaping the rings. When you buy piston rings you usually buy them for a specific application and they come "pre-gaped" spec'd like spark plugs do. When you install the rings you are supposed to check the amount of gap to make sure it's within spec, if it's to tight you can file them until they meet spec. You can also buy "file fit" rings for a particular bore size which allows an engine builder to make the ring gap whatever spec they specifically want.
Neccessary to reBORE or just a hone - severe ring leakage
