Oil Catch can and condensation
- Thread starter Larryjb
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gooffeyguy
Tom
You make a lot of short trips?
Usually a motor will produce condensation inside the crankcase shortly after starting up from being cool. After it gets up to operating temp it takes a little while for that condensation to burn off.
If you only drive it a couple miles then shut it off and it cools back down before driving it again for a couple miles you will see more water, or the oil in the catch can will look milky.
Usually a motor will produce condensation inside the crankcase shortly after starting up from being cool. After it gets up to operating temp it takes a little while for that condensation to burn off.
If you only drive it a couple miles then shut it off and it cools back down before driving it again for a couple miles you will see more water, or the oil in the catch can will look milky.
I'm more than just a few miles, it's a good 25 minute drive each way to work and back.
I have read that some catch cans are poorly insulated which causes significant condensation inside the can itself. I didn't get as much condensation last year, but perhaps it's been more humid here this fall.
I have read that some catch cans are poorly insulated which causes significant condensation inside the can itself. I didn't get as much condensation last year, but perhaps it's been more humid here this fall.
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I'm no oil catch can expert by any means, but I would not expect to see (nor do I see in my oil catch can) large amounts of water.
I've been reading elsewhere that some catch cans that have thin walls produce a lot of condensation inside that doesn't get evaporated out with normal driving. I'll admit I got a cheap catch can, and this may be the result.
I didn't seem to get this much condensation last year. I'm going to assume it's a result of more moisture in the air and cooler temperatures now.
I didn't seem to get this much condensation last year. I'm going to assume it's a result of more moisture in the air and cooler temperatures now.
SnowDrifter
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'Bout par for the course for cold weather. Just drain it more often and don't think much about it.
There are some pros/cons to mounting locations on the catch can.
Mount it somewhere cool (but not where it would freeze): You'll catch more schmoo, water included.
Mount it somewhere warm: Will catch mainly oil particulate, but less water / other VOCs,
I have mine mounted somewhere on the cooler side and just drain it more often, personally. It's on driver's side cowl, next to the master cylinder. It won't freeze if it's cold, but that's about it. The way I see it: Anything that ends up in there, is more junk not recirculating to the intake.
There are some pros/cons to mounting locations on the catch can.
Mount it somewhere cool (but not where it would freeze): You'll catch more schmoo, water included.
Mount it somewhere warm: Will catch mainly oil particulate, but less water / other VOCs,
I have mine mounted somewhere on the cooler side and just drain it more often, personally. It's on driver's side cowl, next to the master cylinder. It won't freeze if it's cold, but that's about it. The way I see it: Anything that ends up in there, is more junk not recirculating to the intake.
I'm having to drain it every day now.
If I don't keep it drained, I get a tapping sound on start up that doesn't go away. If I drain it, the tapping sound goes away within the first few minutes of driving. I have ready elsewhere that the PCV valves can make noise too which would make sense. If the catch can is full of water, the vacuum won't be strong enough to open the PCV valve properly, and the ball valve inside the PCV may rattle.
However, I'm concerned it's more than that. The tapping sound is very regular indicating a lifter may be getting sluggish. I can't think of anything else that could be making such a noise that is related to the PCV not scavenging oil vapours properly.
Given all this, I may be better off deleting my catch can if I am unable to keep it drained.
If I don't keep it drained, I get a tapping sound on start up that doesn't go away. If I drain it, the tapping sound goes away within the first few minutes of driving. I have ready elsewhere that the PCV valves can make noise too which would make sense. If the catch can is full of water, the vacuum won't be strong enough to open the PCV valve properly, and the ball valve inside the PCV may rattle.
However, I'm concerned it's more than that. The tapping sound is very regular indicating a lifter may be getting sluggish. I can't think of anything else that could be making such a noise that is related to the PCV not scavenging oil vapours properly.
Given all this, I may be better off deleting my catch can if I am unable to keep it drained.
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Have you checked your PCV valve for proper operation?
@Joseph Garcia You're right Joseph, I'll have to check that too. That may be a reason why the water never gets evaporated while driving either.
Anyone ever heard of bad PCV's wrecking lifteers? I sure hope not. Those would be a real PIA to change.
Anyone ever heard of bad PCV's wrecking lifteers? I sure hope not. Those would be a real PIA to change.
Just to update:
I have been emptying the catch can every day and the lifter tapping is much better. I get about a tablespoon of condensation every day at the moment. This was an inexpensive catch can and it won't hold much before it fills up.
I have been emptying the catch can every day and the lifter tapping is much better. I get about a tablespoon of condensation every day at the moment. This was an inexpensive catch can and it won't hold much before it fills up.
SnowDrifter
Full Access Member
I've heard of bad PCVs causing all sort of trouble by means of failure cascade... But not directly against well... Anything.
Usually it'll manifest itself as oil usage, then progress to seal failure - particularly around the spinny bits. I honestly can't really fathom why it would have any direct influence on lifters / tapping...
The only thing I could rationalize, and it's a realllllll long shot, is some sort of buildup on top of your intake valves that's clearanced *just* right so when the engine is warm(and expands), it doesn't strike anything. And that by filtering your crank gasses, you're preventing a regenerative buildup and allowing the detergents in the fuel to clean/degrade them.
Usually it'll manifest itself as oil usage, then progress to seal failure - particularly around the spinny bits. I honestly can't really fathom why it would have any direct influence on lifters / tapping...
The only thing I could rationalize, and it's a realllllll long shot, is some sort of buildup on top of your intake valves that's clearanced *just* right so when the engine is warm(and expands), it doesn't strike anything. And that by filtering your crank gasses, you're preventing a regenerative buildup and allowing the detergents in the fuel to clean/degrade them.
I decided to ditch the catch can. Perhaps it was because it was a cheap one, or its the climate here, but I was having to empty water out from it daily. Furthermore, there was so much moisture it was collecting in the PCV itself. That means that there would be moisture under the valve covers that wasn't getting removed.
Just to clarify, I'm not losing coolant, certainly not enough to equal the amount I was dumping each day from the can. The moisture must have been condensation.
It was a nice idea while it lasted, but at the moment it will be doing more harm than good so out it comes. I may try a more expensive one in the future.
Just to clarify, I'm not losing coolant, certainly not enough to equal the amount I was dumping each day from the can. The moisture must have been condensation.
It was a nice idea while it lasted, but at the moment it will be doing more harm than good so out it comes. I may try a more expensive one in the future.
