Rings aren't bedded yet, needs more vacuum overun.
Depending on speed 3rd and 4th over run, helps pull the rings to the bore and bed the rings, oil control rings especially as they are ported to the crankcase through the piston...
Morning all,
My engine I'm currently running in is a 4age, i fabricated a small 650ml catch can out of stainless with 2X inlet ports and 1 uni filter breather. I have a late model 4age block that has a crank case port on the rear left of the block, this normally aids in draining oil from the head but since i have a bigport head this drain point doesn't exist. I have since plumbed this crankcase outlet into the catch can as well as the factory cam cover breather.
Now the motor is probably 150km old, and I'm finding a tainted amount of oil in the catch can every short stint of driving.. it smells moderately of fuel.
I'm just curious to know if this is just normal blow by as the rings bed in, or should i be adding a baffle in the crank case hose as it seems that's where its all coming from.
All idea's theories, and past experience welcome
cheers,
Case
Rings aren't bedded yet, needs more vacuum overun.
Depending on speed 3rd and 4th over run, helps pull the rings to the bore and bed the rings, oil control rings especially as they are ported to the crankcase through the piston...
There is a lot going on here Casey. A lot more we need to know & heaps to argue about.
Was this rebuild, new bores, new pistons & new rings, or was it old bores, old pistons & new rings ? Did you hone the bores, & what type of hone ? Are the rings chrome or cast iron ?
What oil are you using ? How are you running it in ?
If you can answer these questions, I can give a more accurate diagnosis of what is going on.
150 k, this should not be happening & I fear that that you missed the most important window for sealing your rings with combustion pressure in the first couple of k's.
Owen.
What he ^^^ said. Block the oil drain port off, and just vent from the standard cam cover vent.
Cheers... jondee86
Cheers cuzzo I had a feeling that was the case, though the oil in the sump is still pretty clean, really nothing like the stuff coming ot the catch can.
As for re: missed window, I doubt this has happened, orig bores and pistons, new chrome rings, crosshatched honed bores.
The engine doesn't miss a beat nor blow any smoke, I was just hopping I can utilize this crank case breather bu it seems like it's a waste of my time and should tap a thread in the head to allow drain back like it was originally made for, might just add some bigger breather lines on the next set of cam covers
"Does it go to atmo" means does it go straight into the atmosphere/air
Not here anymore!
is it running rich?
"I'm a Teaspoon, not a mechanic"
"There is hardly anything in the world that a man can not make a little worse and sell a little cheaper" - John Ruskin (1819 - 1900)
AU$TRALIA... come and stay and PAY and PAY!!! The moral high horse of the world!
Yes to atmosphere and yes slightly rich.
Okay, i've just gone over the whole engine and i have got a vac leak around the inlet manifold flange its actually pretty bad, could this contribute to anything? at about 200km now and it has since reduced in amount how much oil gathers in the catch can, so yeah not really sure whats going on just yet but im thinking it was just blow by from un-bedded rings and its now bedding in thus reducing blow by??
will pull the manifold off, by new gaskets, install half size rad, fab up the turbo manifold, install the turbo, wastegate and all associated plumbing, drop the oil, change the filter and then do the remaining 750-1000km's on the run in and then slowly introduce boost.
might have to make a new catch can yet (bigger) but we'll see
Other things like vavle stem seals 'bed in' to, could play a small part.
you dont have to slowly introduce boost, give it the whole lot, just dont keep it singing in the top revs for ages.
around 3000ks to bed the rings in "proper". i only do around 300 then it goes on the dyno.
that c/case breather would have played a big part in filling the can, just cap it off if you dont use it.
i dont have a funny or cool signature.
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