Valve cover breather

[Adf]

My first tractor: B7200. The breather tube that comes off the top of the valve cover exhausts oily and drips on oil filter. Is the problem worn valves or is this normal

 

[Dave_eng]

My first tractor: B7200. The breather tube that comes off the top of the valve cover exhausts oily and drips on oil filter. Is the problem worn valves or is this normal

Some "blow by" is normal. An excess amount is usually worn piston rings.

Depending upon where you live, you could extent the tube so it is not landing on the machinery. If you are in a cold climate you risk the tube freezing and then crankcase pressure goes through the roof and can blow oil seals.

Dave

 

[North Idaho Wolfman]

My first tractor: B7200. The breather tube that comes off the top of the valve cover exhausts oily and drips on oil filter. Is the problem worn valves or is this normal

Blowby is normal on these, but it sounds like you might need to take off the valve cover and clean the cover and the vent baffle in the cover.

What type and weight oil are you running in it?

 

[Adf]

I'm not sure of oil weight. It Came with fresh oil change. Hour gage says 506 hours on unit. It doesn't smoke from exhaust after warm up. It drips enough to make a mess on the bottom of the oil pan and leave a few drips if idling on driveway.
Thanks for the responses . Much appreciated.
While I have a thread:
The steering wheel has way too much play in it. To get at the steering box I need to take off dash board right? I'm assuming there is an adjustment nut or screw to tighten it up.
I bought this first tractor from a son who was selling it because his dad who owned it passed away. He didn't know much about it and neither did I. It had low hours on it and seemed to have a tight motor and still have the original rear tires to substantiate it not being worn out, but then I don't know for sure. Maybe I need to do a compression test on cylinders?

 

[Dave_eng]

I have attached the Workshop Manual page dealing with steering adjustments.
It looks like no removal is required.

Suggest you go to this site and download free Owners' and Workshop manuals for the B6200-B7200 tractors.

http://kubotabooks.com/AutoIndex/index.php?dir=Tractor Owners Manuals/

Diesel engines which are not worked hard can develop a condition wherein the piston rings are not seating against the cylinder walls. This results in more blow by and sometimes oily gunk in the exhaust. Common term is diesel slobber.

Making your tractor work hard is doing it a big favor. With only 500 hrs perhaps your tractor is in need of a good work out.

Dave

 

[GreensvilleJay]

I replumbed the 'blowby' back in the air intake on my Buda BD153 diesel that powers my Allis-Chalmers forklift.
I got fed up of the huge amount of blowby oil dripping onto the engine and then the floor. Dang near impossble to get off conrete pavers !

 

[Adf]

Wow!! Super info. Thanks a million. I went from being lost on this rig to being found by your responses.

 

[D2Cat]

Yes, your problem may be as suggested, diesel slobber. Put an implement on your tractor and work it. The harder the better for a couple of hours, and I'll bet you see a difference in the oil dripping.

 

[BruceP]

An "oil catch can" could be added to that breather hose.... just remember to drain it once in awhile.

Also consider changing the motor-oil you use. Some brands of oil are KNOWN to 'outgass' more than others. (MOBIL1 is one of those)

ROTELLA t6 5w40 is a VERY good oil with little inherent blowby. Sometimes, older engines prefer a slightly thicker oil to help seal things up.

Also, if you think your piston rings are sticking... consider some kind of "engine clean" process. (like treat with MMO) What have you got to lose except to free up the rings?

Basic procedure:
1) remove glowplugs and fill cylinders with MMO
2) Let sit for as long as possible (days/weeks)
3) Lie an old towel over the still-open glowplug holes and crank engine to blow out the excess. (this will make a MESS)
4) Reinstall glowplugs
5) Change oil (cheep oil is fine) and use at least one quart of MMO in crankcase
6) Run engine for awhile with MMO in crankcase to wash off internal crud. (perhaps 6-10 hours of use)
7) Do final oil-change with QUALITY oil.

MMO=Marvel Mystery Oil

 

[GeoHorn]

.

Also consider changing the motor-oil you use. Some brands of oil are KNOWN to 'outgass' more than others. (MOBIL1 is one of those)

Horsethit!

Let’s don’t let this slide into a “favorite brand of oil” argument.

Mobil 1 is not what I use and so I’m not trying to defend it, but oil-brand-arguments are foolish B.S. when it comes to serious mechanical maintenance issues.
Blow-by condensation is more likely when engines are little-used, rarely run until fully warmed/hot and used in cold climates for short periods.

The idea of a catch-can and redirecting the hose and checking condition of the vent/baffling is useful info however.

 

[North Idaho Wolfman]

MMM=Marvel Mystery Oil

MMO=Marvel Mystery Oil

MMM=Mid Mount Mower

No confusing the new guy!

 

[dlsmith]

Also consider changing the motor-oil you use. Some brands of oil are KNOWN to 'outgass' more than others. (MOBIL1 is one of those)

Never heard of engine oil "outgassing", in fact a Google search doesn't return any references to that assertion.

Care to cite your source for that "KNOWN" fact?
Just curious.

 

[lugbolt]

Typically when you get excessive "blow-by" (which is what you're seeing out of your vent tube), the engine is worn. No amount of band-aiding with different oils is going to fix it; that's been tried over the years with additives, etc, and, well basically none of it actually works. The only thing that is proven to work is a rebuild that is done properly.

 

[BruceP]

Never heard of engine oil "outgassing", in fact a Google search doesn't return any references to that assertion.

Care to cite your source for that "KNOWN" fact?
Just curious.

Good question! The term 'outgassing' was my own... I believe the more technical interpretation is when light hydrocarbons tend to vaporize out of a motor-oil. There is ABSOLUTELY a difference among motor-oils in this regard.

In discussions of gasoline engines with DI (Direct Injection), there is an ongoing discussion regarding the intake-valves getting carbonized. This is because the PCV system sucks the vapors from the crankcase into the intake manifold. These vapors contact the hot intake valves and turn into a hard carbon coating.

Previous engine designs (before DI) did not have this problem because the injectors spray DIRECTLY on the intake valves which continuously keep them washed off and clean.

it has been made known that some motor-oils will vaporize more than others leading to intake-valves getting carbonized more quickly than when one chooses to run a less-vaporizing oil.

As people become educated on this phenomenon, it has been found that MOBIL1 will vaporize more than some other motor-oil choices.

There are some folks who have made youTube videos by "cooking" various motor-oils and weighing the loss of mass. This is a clear indication of how much of the original oil was lost due to 'outgassing'

 

[Pau7220]

Same guy who did the AntiGel test..... Project Farm channel. I've watched quite a few of his videos. Just about as honest and objective as it gets.

https://youtu.be/a9DWGtXpYUc