Let me start by saying this is not related to my turbo accord it still runs...i notice on past engine (N/A set-up) that ever time i blew a engine it was always the number one journal that was messed up. is the some reason for the number one cylinder on the crank rod bearing always being the first to seiz up and the only?
when you've built the engine, do you bet the crank oilways chamfered so the bearings get a better oil spread?
no, "bet"? what is that, to open or port? that wont throw the crank off? and im talking about the factory setting....
how many engines have you blown, and what kind of engines are you talkng about about specifically?
Crank journal bearings toasted? usually comes from poor oil maintenance , contaminated or lack of oil, and normally happens over time.
If you are dealing with a big bored out motor, a juiced or forced induction (esp aluminum block) you would have a chance the block distorted and caused the crank to favor one spot.
Last edited by 2oodoor; 08-22-2008 at 06:58 AM.
sorry, bad spelling
getting the oilway outlets chamfered is sort of like counter sinking the hole.
it just lets the oil coming out of the crank at the bearings spread across the bearing face in a more uniform way. it opens up the oil feed at the opening by best part of 50% so you can imagine how much better the spread of oil is going to be.
it shouldnt throw out the balance of the crank if done by an expert
most cranks have this done from factory to an extent, but when you start adding extra stresses to the bottom end, eg turbo charging or bumping the compression, its always a good idea to have the crank "race prepared" just for peace of mind if for nuthing else.
when they do that, they generally cross drill and enlarge the oilways,chamfer the openings at the bearings,machine and polish the journals and balance it.
just make sure to give the machine shop the front pulley,flywheel and clutch aswell so it can all be balanced at the same time.
oh ok... and im talking about the a20a3 86-89 FI blocks. now back then i never worked on my cars like now. but you never know how a piston skirt or anything unless you crack it open. but those were replacement engines from the J.Y. but ill have the machine take a look into this, HRT will be doing this for more than lightly.
am i the only one with this problem?
quick answer= oiling issue, excessive end play, improper bearing size from being patched up previously.
the oiling issue could be the oil pump, they can leak internally (rubber seals) and lose psi intermidantly.. that is the only A20xx model specific oiling issue I know of on these. There have been threads on the oil pressure relief, you may want to search on the mod for the relief valve that increases oil pressure if you need that. It is in the how to or FAQ section I think.
ima just put a new oil pump on my car then. the original one can last 20+yrs a new will do the trick. increasing the oil pressure will end-up damaging the bearing also..cant remember what its called put it'll force the bearing outward, on the rod bearing and cause you to throw a bearing. you know what im saying?
increasing the oil pressure is more likely to blow oil seals than anything else.
never heard of it hurting bearings tho.
old aston martins run up 100psi with out problems.
thats a whole nother car, with a whole nother crank...but, too much oil pressure in certain cars can damage bearings
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