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Location:
caibs
Registered:
January 2005
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4agze crankcase pressure
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Wed, 30 November 2005 06:28
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g'day.
i have a 4agze from a ae92, and its having a few problems at the moment.
basically, theres bulk crankcase pressure and it has blown the oil filler cap off twice. luckily both times have been short trips so no damage has been done. if i take the oil cap off and run the car, there is alot of air being forced out of the hole.
another thing, there is no pcv valve (that i'm aware of) - as at the back of the rocker cover theres a hose just venting atmo.
so. the question would be something along the lines of
what are the causes of excess crankcase pressure
what do you reckon is rooted on mine
what can i do to fix it
cheers fellas
-caibs
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Location:
Bundaberg, Qld.
Registered:
May 2002
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Re: 4agze crankcase pressure
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Wed, 30 November 2005 08:19
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these engines have a positive crankcase, so a fair bit of air does come out the oil filler hole when you take the cap off. plus no pcv valve, just a pipe from the inlet cam to the inlet before the TB.
check the pipe that comes from the inlet cam to the inlet (or in your case hanging there it seems) and make sure it's not blocked.
excessive crankcase pressure can be worn rings, have you done a compression test?
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Location:
Adelaide
Registered:
May 2003
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Re: 4agze crankcase pressure
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Wed, 30 November 2005 08:22
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hey man.
sounds like you have excessive blow by. which is compression going past the rings into the crankcase. might pay to do a wet and dry compression test to see if there is a cylinder down on compression. if this is teh case then its rebuild time....
it could also be boosted air going into the rocker cover from the supercharger. but if the pcv setup is factory then i doubt its that.....but if you have modified the breather setup to go into the intake after the supercharger, then this could be the fault.
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Location:
caibs
Registered:
January 2005
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Re: 4agze crankcase pressure
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Wed, 30 November 2005 14:30
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i'll do a comp test tomorow, i've got a feeling its in need of a re-ring though, judging by the amount of oil its spitting out the breather it would seem like its getting ring flutter on higher revs. hopefully the bores are ok.
i'm a bit of a rookie with the gze's, dont really know all that much about em. so, a few questions
is the inlet cam the one with the oil cap on the rocker cover (supercharger side) ?
my breather setup is both outlets on the rocker cover are just hoses venting to the atmo (not blocked either). should they be hooked up to something?
not too worried if its farked, its my daily driver so its not a huge deal if something goes wrong - but on that note, if i can fix it before it becomes a problem that'd be orse.
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Location:
Montrose, VIC
Registered:
May 2002
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Re: 4agze crankcase pressure
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Wed, 30 November 2005 21:32
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Inlet cam is the one above the inlet manifold 
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