Cold weather driving GDI

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738
Location
New Hampshire
Maybe this isn't the right place to post this, but can cold weather driving help with cleaning the valves on a direct injection engine? Emptied my catch can the other day, and just like every time this winter it's filled with what looks like a lot of water. Summer was different, it appeared to be mostly oil. The school of thought is that water can clean carbon deposits - at least that's what I always heard...how we used to pour a little water down the carb and it'd clean the carbon off those pistons. I'm running Pennzoil Platinum 0w20 in my truck, it calls for the 0w20. I installed a catch can because I was concerned about the amount of oil that seemed to be tracking into my intake (truck only had 10,000 miles at the time). I have 26,000 miles now. But when I'm emptying this can and I see that mixture of water and oil...and when I see that white smoke blowing out of the tail pipe all the way through my 40 mile commute (it's been real cold up here) I think...is the PCV introducing a fair amount of water into that intake, onto the valves...and is it actually doing more good than harm? And believe me there's a fair amount of water...enough to freeze the contents in the can solid (it's been bellow 10 degrees every morning this week....-3 on Tuesday). I know I'm reading into this a bit too much. And I know direct injection has gotten into my head. Lol.
 
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36,248
Location
ME
I think you're asking if the humidity will do a "water injection" type cleaning. There's less absolute humidity in winter, so I guess not. However, you might get a slug of water from your catch can when it thaws out, which is more effective than drop-by-drop.
 

Railrust

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738
Location
New Hampshire
Originally Posted by eljefino
I think you're asking if the humidity will do a "water injection" type cleaning. There's less absolute humidity in winter, so I guess not. However, you might get a slug of water from your catch can when it thaws out, which is more effective than drop-by-drop.
Yeah that's what I was thinking, if the condensation from a cold engine is benefiting valve cleaning through the PCV, during cold weather. But I guess the water in my catch can could also be forming because the can is cold and the crankcase gases are warmer?? And I neve even considered the humidity from the summer...so all things being equal, or not quite equal...I guess it probably doesn't change or help much of anything.
 
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656
Location
Alberta
The bit of water vapour your catch can is trapping would not do anything for cleaning the valves IMO. If the catch can is actually preventing a significant portion of oil vapour from reaching the valves, that would do more good.
 

JAG

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5,320
Location
Fredericksburg, VA
I think that even in the winter, there is too much oil in the oil/water mixture passing through the PCV for it to have a net cleaning effect in the combustion chambers. Motor oil's base oil molecules are are so large that they tend to leave behind a lot of carbon when combusted in an engine, compared to gasoline Also, I think the water needs to enter the chambers in liquid phase, then go into the gas phase to break deposits loose.
 

Railrust

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738
Location
New Hampshire
Originally Posted by JAG
I think that even in the winter, there is too much oil in the oil/water mixture passing through the PCV for it to have a net cleaning effect in the combustion chambers. Motor oil's base oil molecules are are so large that they tend to leave behind a lot of carbon when combusted in an engine, compared to gasoline Also, I think the water needs to enter the chambers in liquid phase, then go into the gas phase to break deposits loose.
Yeah this^^^ is what I wasn't sure about, the oil water mixture.
 
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25,413
Location
MA, Mittelfranken.de
Originally Posted by JAG
I think that even in the winter, there is too much oil in the oil/water mixture passing through the PCV for it to have a net cleaning effect in the combustion chambers. Motor oil's base oil molecules are are so large that they tend to leave behind a lot of carbon when combusted in an engine, compared to gasoline Also, I think the water needs to enter the chambers in liquid phase, then go into the gas phase to break deposits loose.
Not really, I have seen engines using a bubbler system years ago that were spotless in the combustion chambers and intake valves.
 
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3,649
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St. Charles County, Missouri
I had some kind of water injection (bubbler bottle) that I got from JC Whitney in the seventies. Ran it on a '72 Renault R16. Don't know if it did a thing. Thanks for the memory, if that's what you're talking about.
 
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2,046
Location
Oregon
Originally Posted by JAG
Trav, will you please describe that bubbler system?
I assume the "air intake adjuster" side goes to the valve cover... or perhaps not, as that would gum up the entire system. Probably only works with open air style valve cover breathers. [Linked Image]
 
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2,401
Location
WY
Fill your catchcan 1/2 way with -34F windshield de-icer. if you are inleting any vapor towards the valves the methanol at least has a chance of possibly breaking down the carbon.
 

JAG

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5,320
Location
Fredericksburg, VA
Originally Posted by 1JZ_E46
Originally Posted by JAG
Trav, will you please describe that bubbler system?
I assume the "air intake adjuster" side goes to the valve cover... or perhaps not, as that would gum up the entire system. Probably only works with open air style valve cover breathers. [Linked Image]
Thanks. That is clever.
 

Railrust

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738
Location
New Hampshire
Originally Posted by 1JZ_E46
Originally Posted by JAG
Trav, will you please describe that bubbler system?
I assume the "air intake adjuster" side goes to the valve cover... or perhaps not, as that would gum up the entire system. Probably only works with open air style valve cover breathers. [Linked Image]
Interesting, I'll have to look into this...never heard or seen something like this before.
 

Railrust

Thread starter
Messages
738
Location
New Hampshire
Originally Posted by sloinker
Fill your catchcan 1/2 way with -34F windshield de-icer. if you are inleting any vapor towards the valves the methanol at least has a chance of possibly breaking down the carbon.
Never heard of this before, sounds interesting. At the very least I may try it just to prevent contents in the can from freezing.
 
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2,180
Location
South Carolina
Originally Posted by 1JZ_E46
Originally Posted by JAG
Trav, will you please describe that bubbler system?
I assume the "air intake adjuster" side goes to the valve cover... or perhaps not, as that would gum up the entire system. Probably only works with open air style valve cover breathers. [Linked Image]
The "air intake adjuster" just went to the atmosphere. My brother and I built these and used them on our vehicles in the '70's. Using a plastic jar (mayonnaise or peanut butter) and aquarium hose. The "bubbler" was an aquarium stone. We hooked ours straight to engine vacuum on the carb but we experimented with attaching it to the spark advance port. Theory was the more you stepped on the gas the more it would suck. We never figured out how to keep them from freezing in the Winter.
 
Messages
25,413
Location
MA, Mittelfranken.de
Originally Posted by JAG
Trav, will you please describe that bubbler system?
Others have posted the basics of Ron Novac's system but today with modern electrics it can be improved upon without much drama. Instead of allowing air into the bottle from the open air a small nipple in the air cleaner box post filter will insure only clean air enters the system. A small thermostat controlled solenoid that allows the vacuum to be applied to the system only when the engine reaches x degree is a good add on. This is the original system, you add alcohol to the water in winter. Yes it works and works pretty well but like catch cans it requires some amount of constant user maintenance to keep water in it. I would use a tin top glass jar like the old MMO oilers or caning jar and a band clamp to secure it. http://journeytoforever.org/biofuel_library/ethanol_motherearth/me3.html Edit: The intake air is not adjusted only the the vacuum side, it has nothing to do with valve cover breathers. It uses an air stone for a fish tank on the intake air side to make the bubbles.
 
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Messages
1,776
Location
Kingston
Not a GDI but I just emptied my catch can on my 83 Caprice today and it's been driven about 1200-1500 miles short trips in extremely cold weather lately. Way less moisture than I have seen in some people's catch can pics for some reason.

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Railrust

Thread starter
Messages
738
Location
New Hampshire
Originally Posted by caprice_2nv
Not a GDI but I just emptied my catch can on my 83 Caprice today and it's been driven about 1200-1500 miles short trips in extremely cold weather lately. Way less moisture than I have seen in some people's catch can pics for some reason.
Yeah I'm getting maybe twice as much as that with the same mileage. Then again I'm using probably a much lighter weight oil and have GDI. The water bubbler system sounds interesting.
 
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