Kioti Dave
Gold Member
It has been pretty cold here lately in Western Canada. Today, engine blew out crankcase dipstick due to high pressure. I am assuming that a vent hose is frozen. Anyone else see this happen to them?
NX crankcase pressure
- Thread starter Kioti Dave
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justman777
Platinum Member
All of these odd issues with people in the cold North make me glad to live in Texas! It was 72 degrees Fahrenheit here today. Had to turn on the AC because the house was getting warmish and muggy. Can't open the doors due to it being Mountain Cedar season. If you live in South Texas, you know what that means...
But to answer your original question, no, I haven't had that happen. Shouldn't the PCV or other valve take care of excess pressure? Do these things even have one? Hmm...
But to answer your original question, no, I haven't had that happen. Shouldn't the PCV or other valve take care of excess pressure? Do these things even have one? Hmm...
xcgreene
Platinum Member
Most newer diesels do have a Positive Crankcase Ventilation valve (PCV) Some of them can freeze up if its a certain type and in the right situations. If you only ran the engine in short stints, where there was enough moisture still steaming off in that PCV system, then shut down during a very cold snap, I have seen this happen before. blew the dip stick right out of the tube. Not good for the engine seals, don't run it this way if you can avoid it. An air dryer of sorts over the PCV valve will free it up.
On an older tractor, I had some mud wasps make good use of the crank case vent tube, plugged it up real good. Found out in a similar fashion.
On a 22r Toyota gasoline engine I've seen the front main seal blow out due to a stuck PCV valve while driving. Oil everywhere in the engine bay. Looked like this one had gummed up, as opposed to freezing.
On an older tractor, I had some mud wasps make good use of the crank case vent tube, plugged it up real good. Found out in a similar fashion.
On a 22r Toyota gasoline engine I've seen the front main seal blow out due to a stuck PCV valve while driving. Oil everywhere in the engine bay. Looked like this one had gummed up, as opposed to freezing.
Kioti Paul
Silver Member
My older (DK45) has "positive" crankcase venting, but it simply consists of a (very short) hose that runs from the valve cover to the intake manifold. Because there is no throttle (air) valve, there is no need to have a PCV valve to restrict manifold vacuum loss at low power settings.
I cannot visualize how a PCV valve could work in a diesel, or why there would be any need for one. I do agree if you have (any measurable) crankcase pressure, it can be very detrimental to your crankshaft seals. My crankcase vent hose runs from the rear of the valve cover, to the rear of the intake manifold, maybe 1 foot long.
I cannot visualize how a PCV valve could work in a diesel, or why there would be any need for one. I do agree if you have (any measurable) crankcase pressure, it can be very detrimental to your crankshaft seals. My crankcase vent hose runs from the rear of the valve cover, to the rear of the intake manifold, maybe 1 foot long.
OP
Kioti Dave
Gold Member
Had to rub it in hey!
it's was minus 42 here the other day. ( same in farenheit or celcius) after I let the tractor sit for a few minutes it was fine. Did it once last winter as well. The hose from valve cover seemed fine. Something is frozen.
K5lwq
Elite Member
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Pretty sure everything is frozen at those temps! That is crazy cold!!
Kioti Paul
Silver Member
We're laughing now....You will get your laughs in July, when it is 105 here!
xcgreene
Platinum Member
Here's a snip from the Kioti manual for the DKse tractors. Really isn't much going on there, but #11, the oil baffle plate, would be easy to have a look at.
If OP can rule that out, its one more thing off the troubleshoot check list.
OP
Kioti Dave
Gold Member
One other thing I forgot to mention. There was engine oil coming out the muffler. Probably due to increased pressure in engine? After the crankcase pressure went away and the excess oil in the muffler burnt off it all seemed fine. No mention of PCV in shop manual.
justman777
Platinum Member
Are you using a block heater?
OP
Kioti Dave
Gold Member
Yes, do use a block heater. This did happen last winter as well. That may be why my rear main seal began to leak. Will have to be careful not to run when this happens again. I try not to use tractor when it is very cold, but when the driveway snows in.... I am concerned this may happen again. Would there be any harm in tapping into fill cap to add another bypass to avoid any seal damage?? If it is a design flaw, what could a person do to avoid this?? I guess a heated shop would solve that.
justman777
Platinum Member
Took a look at the service manual. These tractors do have a PCV valve. Sits on top of the valve cover on the end opposite the fill cap. It has a circular metal cap over it that is attached by what appears to be three screws. The blow-by hose looks like it's 3 or 4 inches in length and is connected to the PCV valve and goes into what appears to be the intake manifold. I'd open that up and see what you can see.
OP
Kioti Dave
Gold Member
Yes, it is finally going to 'warm' up to 0 celcius tomorrow, 32 in your world. Will have a good look. I will have to remember to ask about the heat in the summer.
Thanks for the help.justman777
Platinum Member
Yes, it is finally going to 'warm' up to 0 celcius tomorrow, 32 in your world. Will have a good look. I will have to remember to ask about the heat in the summer.
No problem. Helps me learn things about my own tractor!
You may try a hair dryer or heat gun to warm up the PCV valve or bypass hose before you use your tractor. Seems if your issue goes away after the engine runs for a bit and warms everything up, something freezing up would be a likely cause of your issues.
OP
Kioti Dave
Gold Member
On my 2016 model, there appears to be a 3/4" rubber hose about 10" in length that goes from side of valve cover to intake tube. There is no PCV valve visible. Fired up tractor and no pressure build up. Can't see how the 3/4 " rubber hose could get completely plugged. Will take apart intake to see if there is a valve inside?
xcgreene
Platinum Member
That snip I took in post #8 of this thread is a screen grab from the kioti Workshop manual. and should be exactly what the DKse and most likely NX series tractors have.
I'm shooting from the hip here, but it is possible that the oil heater, if its not big enough or hot enough for extreme colds, may be causing the problem. If only the bottom of the engine is hot, moisture will rise up to the valve cover area, and if there is not enough heat to keep pushing the moisture out of the engine entirely, and it is super cold, The moisture will condensate and freeze back up right at the top, where the pcv system is. Especially if the engine is only run in short increments in the cold, where it does not have time to steam off all moisture gathered.
Worth a check during the next hard freeze, to see if your valve cover is still well below 32deg with the heater still on.
This is one of the reasons I prefer the lower radiator hose jacket water heaters, as opposed to the sump pad type. The hot water really gets around the whole engine with the former, if its big enough.
I'm shooting from the hip here, but it is possible that the oil heater, if its not big enough or hot enough for extreme colds, may be causing the problem. If only the bottom of the engine is hot, moisture will rise up to the valve cover area, and if there is not enough heat to keep pushing the moisture out of the engine entirely, and it is super cold, The moisture will condensate and freeze back up right at the top, where the pcv system is. Especially if the engine is only run in short increments in the cold, where it does not have time to steam off all moisture gathered.
Worth a check during the next hard freeze, to see if your valve cover is still well below 32deg with the heater still on.
This is one of the reasons I prefer the lower radiator hose jacket water heaters, as opposed to the sump pad type. The hot water really gets around the whole engine with the former, if its big enough.
justman777
Platinum Member
If you take a look at XCGreen's earlier post with the picture, it shows the valve cover assembly. To the rear of the valve cover assembly is a round cap held on by three or four screws. The picture only shows three, but I suspect there's a fourth screw on the backside. That round cap covers the PCV valve. The tube you found (blow-by tube) comes from the PCV valve and goes to the intake manifold. If you pop that cap off, the PCV valve should be underneath it.
Also, XCGreen is correct in that the DK and NX series share common engine configurations. The graphic he posted is the exact same in the NX workshop manual. The graphic I referred to in order to find the PCV valve is on page 3-80 of the NX workshop manual. The one he posted is found on page 3-41 of the NX workshop manual.
OP
Kioti Dave
Gold Member
I think you guys are correct. My shop manual from 2016 doesn't have the same photos, so thanks for the diagram. It does take forever for the engine to warm up. Think a block heater and an oil pan heater would help? The engine was at operating temp when this happened though. After I let it sit for 15 minutes it was fine (shut the engine off) Can the PCV get 'stuck'?
xcgreene
Platinum Member
Yes they can. Have a look at this screenshot here, a different view than before. Just take the 4 screws out and have a look at the baffle plate, #5. It could be gummed up stuck against the seal.
A quick thing to rule out while troubleshooting, and with some luck, it could solve your problem.
OP
Kioti Dave
Gold Member
Thanks for the picture. Will take apart when it is warmer. Sure miss the old tractor. Looks like I may have to take off hood just to have room to get this apart. :confused2:
