Reuse Oil from Catch Can?

[Fishfan]

I recently installed a catch can in my 1975 2002 and was wondering if there's any reason I shouldn't put the oil from the catch can back in the engine. 

[dlacey]

That's what most crankcase breathers do: they separate the oil and send it back into the engine... So yours just has a manual step added instead of gravity doing the job.

[jimk]

If the water in has cooked off.  There is moisture in vent vapors and the cans aren't hot enough to boil off the water. (BMW discovered that on a design a few years ago with the vent systems freezing up in cold North American climates.)

[JQ02]

The frothy goo in my catch can does not look like engine oil, but my rings and/or valves are in a serious hurt. I would not reintroduce it into my engine. I'm a month away from rebuilding it.

The oil on the dipstick and when I changed the oil look fine, so I don't think I have coolant in my crankcase or anything.

[Fishfan]

4 hours ago, JQ02 said:

The frothy goo in my catch can does not look like engine oil, but my rings and/or valves are in a serious hurt. I would not reintroduce it into my engine. I'm a month away from rebuilding it.

The oil on the dipstick and when I changed the oil look fine, so I don't think I have coolant in my crankcase or anything.

Mine has a little froth at the top and that's what made me doubt whether I wanted to pour it back in. I did do it the first time but have been having second thoughts ever since. That's why I figured I'd ask. My thought was that replacing the oil lost to the catch can with fresh oil certainly wouldn't hurt anything. Only a slight inconvenience and expense to do so.  

 

 

Edited December 16, 2023 by Fishfan

[TobyB]

NO!

 

t

uses it to make cocktails

[Son of Marty]

How much oil are we talking about? Oil is cheap why take the chance.

[Fishfan]

33 minutes ago, Son of Marty said:

How much oil are we talking about? Oil is cheap why take the chance.

Not a ton, but not an insignificant amount. I think you're right. I mean, in a pinch if low on oil I think it wouldn't hurt but I have a 5 quart jug in the trunk so no need. 

[JQ02]

Cost of risk to engine and subsequent rebuild seems far higher than saving a few pennies on oil. Better to just add and change oil more frequently IMO

Edited December 17, 2023 by JQ02
typo

[Mike Self]

When the engine is cold, you're gonna get some condensate mixed with the oil that is deposited in the can, so i think I'd put that oil in my recycling can.  The amount that's gonna accumulate in there (presuming you don't have worn rings or valve guides) is infinitesimal, so you're not saving a whole bunch of bucks!

 

mike

[FrictionTape]

Bit off topic, sorta, but what brand/style catch can did you purchase?

[Fishfan]

3 hours ago, FrictionTape said:

Bit off topic, sorta, but what brand/style catch can did you purchase?

Amazon.com

WWW.AMAZON.COM

 

Happy with it.