Crank case vent tube

[Nasdaqsam]

Just reading a couple of recent threads on the subject. Oddly enough I just noticed I have been getting a few drops of oily residue on my Toad on the drivers side opposite the coach exhaust. While in for a recent oil change I asked about what could be causing this. They pressure washed the whole underside and determined nothing was leaking but the vent tube. Said it was normal.

Does anyone else get this? The tube right now runs straight down behind the engine and is zip tied to a cross member near the rear of the coach. Not sure re-routing it will help it will just send the droplets to where ever I run it.

[mackwrench]

1st you must verify the engine oil level is correct. Many coach application the "full" mark may actually be overfull. This happens quite often. If the engine is overfull, even a quart or 2 it'll blow it out and makes a mess...

Using Cummins quickserve or a quick call to Cummins using your engine serial number find out the specified amount of oil.
Next time it needs service, drain and refill with the spec amount. Then pull dipstick and see where "full" actually is. The oil level is now your new full mark.


If oil level is correct, then you could have excessive blow by causing engine oil to be pushed out the vent.

Some here have tied a Gatorade bottle or the like to the tube to catch it.

On my older (1999) engine I used a Cummins fleetguard crankcase vent system. It includes a oil/air separator theater is basically maintenance free. I get zero oil from crankcase vent system.

With engine at operating temperature can you feel any air coming from the vent hose?

[texnet]

There are lots of threads that have been posted on this subject. Some have taken a peanut butter jar, cut a hole in the lid for the slobber tube, punched some holes in the top to allow it to breath and attached it to the tube/coach.


You should not bend the tube much as the pressure in the engine needs to escape somewhere!


I had the same problem and investigated multiple suggestions. I finally purchased an inline filter at Tractor Supply but never installed it as I found another issue that was causing the problem. The last time I had the oil/filters changed I requested the shop to ONLY put in the amount of oil that was specified by Cummins for my serial numbered engine. They did what I asked and for about 500 miles I still had a little oil on the front of the toad. After that the toad is dry!!! I marked the dipstick after they put in the amount of oil that Cummins stated. The mark was about half way between the bottom ADD mark and the FULL mark.

[Nasdaqsam]

Originally Posted by mackwrench

1st you must verify the engine oil level is correct. Many coach application the "full" mark may actually be overfull. This happens quite often. If the engine is overfull, even a quart or 2 it'll blow it out and makes a mess...

Using Cummins quickserve or a quick call to Cummins using your engine serial number find out the specified amount of oil.
Next time it needs service, drain and refill with the spec amount. Then pull dipstick and see where "full" actually is. The oil level is now your new full mark.


If oil level is correct, then you could have excessive blow by causing engine oil to be pushed out the vent.

Some here have tied a Gatorade bottle or the like to the tube to catch it.

On my older (1999) engine I used a Cummins fleetguard crankcase vent system. It includes a oil/air separator theater is basically maintenance free. I get zero oil from crankcase vent system.

With engine at operating temperature can you feel any air coming from the vent hose?

Thank you for the reply. I will check next time we do an oil change. And for now add the bottle to catch it. I have not checked for air but will tonight.

[Nasdaqsam]

Originally Posted by texnet

There are lots of threads that have been posted on this subject. Some have taken a peanut butter jar, cut a hole in the lid for the slobber tube, punched some holes in the top to allow it to breath and attached it to the tube/coach.


You should not bend the tube much as the pressure in the engine needs to escape somewhere!


I had the same problem and investigated multiple suggestions. I finally purchased an inline filter at Tractor Supply but never installed it as I found another issue that was causing the problem. The last time I had the oil/filters changed I requested the shop to ONLY put in the amount of oil that was specified by Cummins for my serial numbered engine. They did what I asked and for about 500 miles I still had a little oil on the front of the toad. After that the toad is dry!!! I marked the dipstick after they put in the amount of oil that Cummins stated. The mark was about half way between the bottom ADD mark and the FULL mark.

Sounds like an issue with the dip stick reading. Thanks

[dennis45]

Originally Posted by Nasdaqsam

Thank you for the reply. I will check next time we do an oil change. And for now add the bottle to catch it. I have not checked for air but will tonight.

You are likely aware of this but if not, be careful not to restrict the size of the breather tube when adding a catch can. Any restriction will result in a rise in crankcase pressure and possible oil leaks.

[Nasdaqsam]

Originally Posted by dennis45

You are likely aware of this but if not, be careful not to restrict the size of the breather tube when adding a catch can. Any restriction will result in a rise in crankcase pressure and possible oil leaks.

I was not aware of that, my only knowledge of this was when I asked the mechanic about it I asked if I could put a filter on it. I was told no it needs to remain completely clear and able to breath.

Thank you

[dons2346]

Cummins markets a device that attaches to the blow by tube, collects the oil and re routes the oil back to the crankcase. Cost is around $500

[mackwrench]

Originally Posted by dons2346

Cummins markets a device that attaches to the blow by tube, collects the oil and re routes the oil back to the crankcase. Cost is around $500

Kit part number is fleetguard CV50116, $250.00 from fleetguard. Comes with all hoses, clamps and mounting bracket. Also has very easy to read and follow installation instructions.
I was able to install it in a little over an hour. I've got around 10k miles on setup since I added it.
Maintenance free, no bottle to crawl under and deal with.....and not one, not even a speck of oil from vent.

[Nasdaqsam]

Originally Posted by mackwrench

Kit part number is fleetguard CV50116, $250.00 from fleetguard. Comes with all hoses, clamps and mounting bracket. Also has very easy to read and follow installation instructions.
I was able to install it in a little over an hour. I've got around 10k miles on setup since I added it.
Maintenance free, no bottle to crawl under and deal with.....and not one, not even a speck of oil from vent.Attachment 206909

$250 seems reasonable enough. I will look into this. Thanks

[mackwrench]

Originally Posted by Nasdaqsam

$250 seems reasonable enough. I will look into this. Thanks

Its cheaper than a engine overhaul, and worth a try....If you have any installation questions or issues, shoot me a pm....be glad to help.

[mackwrench]

Here's a few more pics. The vent tube has the 90 degree plastic fitting, then the hose runs up to separator, the smaller hose runs from separator to where the dipstick would be if it was on that side of engine....that's the brass nipple you see in one pic. The instructions noted the separator needed to be mounted 18" above the oil level, which is just below the area where oil pan/engine block bolt together....the vent is where you see my finger in the one pic. I have since ran a little more hose down to the rear mud flap....but really didn't need it.

Cummins has the dipstick hole on both sides of block, depending on application which one is used. There is a small metal soft plug pushed into the dipstick access hole. I used a small sharp point chisel and it pulled right out.....

[mackwrench]

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