Excessive Blow-by on Kama 554

[3RRL]

I'm nearing 500 hours (on the clock) on my Kama 554. I have a couple of questions.

I've noticed excessive blow-by coming from the breather cap on the valve cover. It's become more apparent than before. I can see oil fumes (smoke) getting pushed out the little holes in the breather cap and the valve cover gets oily when it's been running for a long time.
There are no water leaks and the engine runs good. It does not overheat either, but uses oil more than before.
-Does anybody else have that problem?
-Is it normal?
-What causes that and what can I do to fix it?

My Kama doesn't appear to have a crankcase vent like on the Jinmas. What it has is a breather cap on the valve cover but nothing I could see in the crankcase itself.
I took these photos this morning.
They are looking at the left side of the engine where the starter motor is. I want to know what that is, what does it do?



I took the 2 bolts off to remove the cover, but I think it must have a shank or something in it because the cover did not just pop off. Is the cap attached to something? See that screw in the 3rd photo, do I need to loosen it first to take the cap off? I stopped since there is nothing in my manual about it and I don't know what it's for. The starter is in the way of that set screw.

I was thinking of drilling a hole in that cover to add a crankcase vent like on the Jinma if it goes to the crankcase. I can take the starter off to get to the set screw, but I'd like to know what that unit is, first.

 

[greg_g]

Pretty sure your photos are of the cover plate over the (optional) air compressor mounting location. Presumably that lower screw is related. Very good chance it's a set screw as you suspect.

About the blowby - first SWAG is one or more valve guide seals. But first - how old is the oil, when was the last time you had the valve cover off, and exactly where does the valve cover get "oily when it's been running for a long time"?

//greg//

 

[IH3444]

Rob, all diesels have blowby. If this is a tier II certified engine, then I would look for the one way valve that is required by law to sent the crankcase blowby to the intake manifold whenever the engine speed picks up over idle. By EPA law, all tier II engines must recirculate the crankcase blowby through the engine combustion chambers to be burned for a cleaner exhaust. Your oneway valve my have become stuck closed, and the crankcase being virtually ventless, maybe finding anyway out that it can, thereby looking like excessive blowby. Which oil brand are you using also? I am breaking in a new Volkswagen diesel engine with TSC 15w-40 dieselall oil. Put a few hundred miles on it, then changed filter, and oil. Oil now is Rotella 15w-40, and from my dash mounted oil pressure gauge, the Rotella is holding from 10-15psi more at idle, at operating tempertures. I was quite surprised at this. So all 15w-40 oils are not created equal, or hold up as well at operating temperture. You may only need to change the oil, and check your oneway valve.

 

[bluechip]

The KM tractors that were legally imported prior to 2006 (25 to 50HP) were brought in under TPEM exemptions (small volume importers) and do not have any EPA certification at all. The engine crankcase is vented throught the oil filler cap, which has a "steel wool" type filter built into it. The Feidong engine which is manufactured in-house by the Shandong Tractor factory was never EPA certified, the factory simply changed to certified engines from other manufacturers.

 

[3RRL]

Thanks for the replies guys.
Like I said, I couldn't find a crankcase vent of any sort and Chip just verified it.
My question is, is there a place to install one?
Perhaps through that cover which I posted photos of?

Chip...
Can you tell me what that cover and set screw do? Is Greg correct in his assumption that it has something to do with the optional air compressor? Do I need to loosen that set screw to take the cover off? What would I find in there?
Thanks,

 

[3RRL]

I have a couple more questions for you:

- Is there anyway of finding out what that cover is all about? That would be good to know. As far as I know, it is not mentioned in the engine manuals.
- Also, can you point me to where that old breather plug they put in? The one that is blocked off. I would still like to add a crankcase breather, just to reduce the oil residue coming out of the valve cover breather cap.
- What are your feelings about running the breather cap exhaust back into the intake? I discussed that with Larry and he was not to keen on the idea of having residue enter the manifold and possibly building up on the valves.
- What about running it connected to the exhaust stack or exhaust manifold then?
Thanks,

I remember reading that the air compressor was somehow connected to the front of the fuel injector pump casing somehow. Over on the other side of my engine. I thought anyway, that is what I read?
So maybe that cover is for something else.
I'd sure like to know what before I chance taking it off.

 

[bluechip]

Under that mistery cover is a gear that runs on the camshaft and drives the oil pump. the screw at the bottom is a plug into an oil galley.

I don't know of any blocked off breather plug... the breather is in the oil fill cap.

 

[3RRL]

OK Chip,
Thanks for getting that information on the "mystery" cover. I guess I won't be going into that then.

 

[Dave_Lilly]

I'm nearing 500 hours (on the clock) on my Kama 554. I have a couple of questions.

I've noticed excessive blow-by coming from the breather cap on the valve cover. It's become more apparent than before. I can see oil fumes (smoke) getting pushed out the little holes in the breather cap and the valve cover gets oily when it's been running for a long time.
There are no water leaks and the engine runs good. It does not overheat either, but uses oil more than before.
-Does anybody else have that problem?
-Is it normal?
-What causes that and what can I do to fix it?

My Kama doesn't appear to have a crankcase vent like on the Jinmas. What it has is a breather cap on the valve cover but nothing I could see in the crankcase itself.
I took these photos this morning.
They are looking at the left side of the engine where the starter motor is. I want to know what that is, what does it do?



I took the 2 bolts off to remove the cover, but I think it must have a shank or something in it because the cover did not just pop off. Is the cap attached to something? See that screw in the 3rd photo, do I need to loosen it first to take the cap off? I stopped since there is nothing in my manual about it and I don't know what it's for. The starter is in the way of that set screw.

I was thinking of drilling a hole in that cover to add a crankcase vent like on the Jinma if it goes to the crankcase. I can take the starter off to get to the set screw, but I'd like to know what that unit is, first.

Try cleaning or replacing the breather cap ( I am assuming that this is the oil fill cap wth a vent to relieve crankcase pressure from crankcase blow-by). If this doesn't solve your problem, you should look for worn valve guides or worn piston rings, either one of which will cause excessive crankcase pressure to vent out of the only outlet, which is the oil fill\breather cap.
Any home made modifications to the crankcase breather mechanism may fix the immediate problem, but will still result in oil loss due to over pressure of the crankcase which will only get worse the longer you run the tractor before you actually fix the problem.

 

[greg_g]

Try cleaning or replacing the breather cap .

Not on this engine Dave. It's a 90 degree cast iron appendage that's bolted on to the side of the valve cover. It's not a true breather in the in-out sense, it serves more of an exhaust function (and doubles as an aggravating oil fill location). There's nothing inside but a floppy rubber disc that covers half a dozen holes. When pressure inside the valve cover is higher than outside, the flap is lifted to relieve the pressure. Otherwise gravity holds it in place to minimize intruding outside air and moisture.

I disassemble mine for inspection at every oil change, the only thing I've ever wiped out was a little emulsion. That said, it bears inspecting for excess emulsion. If there's a water leak, what looks like blow-by could actually be condensation (like the initial white smoke out of a cold muffler)

//greg//