Oil Catch can finds

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phatz_hatz

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Keep in mind it is 12 degrees here in New York. But decided to see what it looked like in here after about 5 months of driving. Is this discoloration of any concern. 95 Tahoe with TBI
IMG_5033.jpeg
 
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phatz_hatz

phatz_hatz

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IMO, there's nothing wrong with that. I am surprised that you only caught that small amount of oil after driving for 5 months. I catch about 1 oz. of oil for every 1000 miles driven.
Yea i figure it was just from the condensation. To be fair i only drive the truck about 1,000 miles every five months. After i pulled the dipstick i was going to delete this cause that looks fine
 

Marky Dissod

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Would y'all understand, if every time I read a thread about catch cans, I wind up watching videos of Erik Paulson?
 

Double J

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Green in the background, clean in the can
 
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justirv

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Frozen condensation in the pcv circuit can cause engine block pressurization, bad news... bypassing the catch can during severe temp drops isn't a bad idea.
 

Marky Dissod

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i have found that 5w30 ends up with a lot less in the can, which means it must help the valve coking issue in the GMs with no fuel injections.
Besides the fact that 5w30 is in a better spot on the Stribeck curve compared to 0W20 (lool it up),
whatever rate of oil consumption any engine is experiencing, will be greater with 0w20, somewhat less so with 5w30.
Did not say 5w30 is an oil consumption cure, just that 5w30 is less prone to oil consumption than 0w20.
 

Eman85

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What is the reasoning in installing a catch can? Seems pretty needless since it just goes through and burns in the cylinders. These trucks have gone 200k+ mi with no ill effects from the oil in the PCV system being burnt. As far as the moisture that's no big deal either, a little moisture cleans the pistons. Seems like a solution looking for a problem.
 

swathdiver

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What is the reasoning in installing a catch can? Seems pretty needless since it just goes through and burns in the cylinders. These trucks have gone 200k+ mi with no ill effects from the oil in the PCV system being burnt. As far as the moisture that's no big deal either, a little moisture cleans the pistons. Seems like a solution looking for a problem.
Cleaner running engine, greater efficiency. In the old days we just vented to atmosphere with breathers on the rocker covers. Before that they had downdraft tubes.
 

Marky Dissod

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What is the reasoning in installing a catch can? Seems pretty needless since it just goes through and burns in the cylinders.
These trucks have gone 200k+ mi with no ill effects from the oil in the PCV system being burnt.
As far as the moisture that's no big deal either, a little moisture cleans the pistons. Seems like a solution looking for a problem.
I don't NEED a vehicle, but I'm glad I have one, even if I have to keep it clean regularly.
The lil bit of fuel that sneaks past the piston rings and into the crankcase, plus the H2O vapors that make it into the crankcase,
react with each other and form compounds which are not meant to be / are not conducive to productive combustion; basically the stuff that ages motor oil.

Although catch cans are not yet complex enough to guarantee the engine only burns petrol, they help to keep the engine burning more petrol, less of other stuff.
 
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SpareParts

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What is the reasoning in installing a catch can? Seems pretty needless since it just goes through and burns in the cylinders. These trucks have gone 200k+ mi with no ill effects from the oil in the PCV system being burnt. As far as the moisture that's no big deal either, a little moisture cleans the pistons. Seems like a solution looking for a problem.
Take your intake off and turn it on it's side. I bet black nasty looking goo runs out. Catch can will catch most of it.
 

NYBRD

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Oh man I havnt checked mine in months! Woops
 
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phatz_hatz

phatz_hatz

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What is the reasoning in installing a catch can? Seems pretty needless since it just goes through and burns in the cylinders. These trucks have gone 200k+ mi with no ill effects from the oil in the PCV system being burnt. As far as the moisture that's no big deal either, a little moisture cleans the pistons. Seems like a solution looking for a problem.
I installed mine cause i was tired of the ****** pcv hose deteriorating within months and causing a vacuum issues. Plus why not if it’ll catch all that gooeyness
 

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