Kioti DK 35 Crankcase vent question

[Avondale]

My DK35, every now and then, blows the orange rubber cap off the oil filler tube (located just below the alternator) resulting in quite a mess. The rubber plug is "ribbed" but the tube is not. Is this meant as some form of over-pressure relief? I see another rubber tube running from the valve cover to the intake manifold, (which has a recessed device the hose spigot fits on to). I would think this should be the PCV arrangement but it is not shown or discussed in either the owners manual or the Kioti Service Manual. For the record, my engine also has an oil fill cap on the valve cover, too. Anyone with experience on this problem?

[k0ua]

Mine is the SE model, but no I haven't heard of that

[Coyote machine]

Do you fill your engine at the orange cap or at the valve cover? You should ONLY fill the oil at the orange cap NOT the valve cover.
Have you checked to see if your crankcase is overfilled? There should not be enough pressure at the orange cap, which is press fit to the hole.
Have you checked or changed your AIR filter recently for possible blockage?
How many hours on the DK? Does this problem occur only in cold weather? What exact oil and quantity do you have in the machine?
Do you change the filter with every oil change and at what hour interval?

[Avondale]

I have added oil via the valve cover port (labelled ) as well as the tube but the tube port is a bit awkward with my funnel because of the alternator. I do have a ribbed funnel spout but still awkward). The oil level is slightly less than the full notch, about 1/4" or so from full. I have not checked my air filter since the first snow fall, say late Nov 2012. I have 1096 hours on the machine and it has been serviced as per the book. It only happens when it is cold outside but long after the tractor has reached normal operating temp range. I change the oil and filter together and only use OEM filter with specified grade of oil at specified intervals. My manual is out in the garage so can not quote right now, will look up and get back to you about grade and hours at last change. Thanks for your help. PS: will check air filter when next out there too.

[Coyote machine]

Want to reiterate: DO NOT add or fill oil through the valve cover. It can cause cavitation and other problems. Just because it's labeled oil fill does NOT mean that is where the oil for this engine is added/filled. That is partly why the orange cap is used to mark the location for oil to be added/filled. (I believe it is also noted as such in either the owner's manual or the service manual).
Instead remove the lower panel on the right side when the hood is open and add/fill oil at the orange cap ONLY.
If it turns out the air filter is dirty, DO NOT try to clean it. Replace it, vacuum out the area where it goes in the canister, and note the hours on the canister with duct tape.

[Avondale]

Thanks, again. Good idea about marking date. Do you know anything about the short hose that runs from the valve cover to the intake manifold and especially about the device I am guessing might be a pcv type relief for venting off excess pressure? It is not shown in either manual but has 4 "phillips/star" screws holding it into a recessed part of the cover.

[ritcheyvs]

Recommend you research this on one of the online parts sites, like: OEM Parts

[Coyote machine]

Thanks, again. Good idea about marking date. Do you know anything about the short hose that runs from the valve cover to the intake manifold and especially about the device I am guessing might be a pcv type relief for venting off excess pressure? It is not shown in either manual but has 4 "phillips/star" screws holding it into a recessed part of the cover.

As suggested in the post above, look up the part, it's corresponding number and show us a pic.
Have you done what was already suggested, checking air filter condition, etc. Oil you have put in through the valve cover could be your entire issue. Let's verify that first.

[Avondale]

Have not had a chance to follow up due to my main work requirements (12 hr days) and also it is maple season prep time so very little time for much else. I will look into, when able. I have not had to add any oil since the last change less than 100 hrs ago and just ran the machine for snow blowing contract work since (set rpm at about 2000-2200rpm) for majority of work. I mainly filled via the top oil cap (since new) and have also used the side tube before but will now only use the side tube. I have never been advised by the dealer to not use the top cap (marked oil).

[Patches]

There is no issue with adding oil through the valve cover access, so long as you're not tipping a gallon jug into the cover; the issue then is the drain back holes in the head can not keep pace with the rapid oil flow from such as a gallon oil jug and will allow engine oil to "back up" into that vapor recovery tube mentioned. That may cause engine run-away as the excess oil admitted to the recovery system enters the intake manifold and, when the engine is started, the combustion chambers.