Where is the PCV

[RayIN]

PCV valve is normally up under the valve cover. It is used to separate oil from the crankcase vapors and to vent those vapors into the intake manifold. Caution must be used when filling the engine with oil. Too fast and you can fill a cylinder with oil and cause hydrolock. See service bulletin:

file:///C:/Users/Owner/Downloads/Ref%2002%20TC40DA%20Service%20Bulletin.pdf

link says "couldn't find that".

 

[macdoesit]

From what I can tell, the TC30 had two different designed valve covers and the change point is SN 30000. The early ones had the tall breather on the cover with a hose going down from it. I'm just going from the parts diagram on the Messicks site. Hopefully someone else can chime in with more info.....

Thank you. Im trying to stop[ the blue smoke.

 

[macdoesit]

If it was me, I think I'd plug the fitting going into the intake manifold and route the hose from the breather assembly on the valve cover and down the side of the engine to terminate next to the oil pan, which is exactly how my Kubota's are.

If you are getting excessive blowby (oil vapors) that is indicative of an internal engine issue.

No blowby

 

[5030]

I would not get concerned with a gummed up PCV valve then but like I said, I believe I'd plug the fitting and direct the breather hose to atmosphere.

My Kubota's have a sort of valve on the top of the valve cover. It's just a baffle to keep the engine oil from going down the tube and I have almost no blowby either. Little bit but then both units have serious hours on them anyway. 6000 on one and 5500 on the other. My 3406 Cat on the other hand will drip a bit of oil out the road draft tube when it's hot. Keeps the dust down in the gravel driveway,

 

[5030]

Blowby is a factor of 2 different things, first is the passage of the compressed fuel-air mixture past worn rings and the second it the physical design of the internal rotating parts of an engine as it relates to pressure changes internally.

All engines will have some blowby. Worn engines will have more.

 

[macdoesit]

I'm going to try this first, hopefully it will work.

Bar's Leaks Oil Seal Engine Oil Burning & Leak Repair Additive, 16.9 oz​

 

[5030]

Never used that stuff and don't intend to either.

 

[macdoesit]

I can kill the engine and immediately start it again and there is a puff of black smoke, I know this is fuel but why??

 

[toot77]

Seeing as how there was a change in the crankcase venting after serial number 3000, it would help to know what side of that your tractor is on. As mentioned before, pre-s/n3000 just has a vent tube from the valve cover down the side of the engine towards the ground, essentially a road draft tube from pre pvc days. There is no pvc valve. On the post s/n 3000 models, there will not be that tube going down towards the ground. Apparently there is a vent back into the intake manifold, I do not know that there is a pvc here either, I suspect just some kind of baffling.

If you are getting a puff of black smoke at startup only, I am not so sure that is a blowby issue. Blowby is more consistent and and would occur whenever the engine is running, not just at startup. I would suspect a fuel issue, probably with an injector(s)

Also, note that the service bulletin concern about hydrolock only applies to the after s/n 3000 models that have the crankcase vent to the intake and the oil fill is through the valve cover. The earler models with the vent tube from the valve cover down towards the ground will not hydrolock. If you fill one of these too fast, the oil will simply overflow through the vent tube and end up on the ground, or garage floor.

 

[macdoesit]

Seeing as how there was a change in the crankcase venting after serial number 3000, it would help to know what side of that your tractor is on. As mentioned before, pre-s/n3000 just has a vent tube from the valve cover down the side of the engine towards the ground, essentially a road draft tube from pre pvc days. There is no pvc valve. On the post s/n 3000 models, there will not be that tube going down towards the ground. Apparently there is a vent back into the intake manifold, I do not know that there is a pvc here either, I suspect just some kind of baffling.

If you are getting a puff of black smoke at startup only, I am not so sure that is a blowby issue. Blowby is more consistent and and would occur whenever the engine is running, not just at startup. I would suspect a fuel issue, probably with an injector(s)

Also, note that the service bulletin concern about hydrolock only applies to the after s/n 3000 models that have the crankcase vent to the intake and the oil fill is through the valve cover. The earler models with the vent tube from the valve cover down towards the ground will not hydrolock. If you fill one of these too fast, the oil will simply overflow through the vent tube and end up on the ground, or garage floor.

There is no blowby. Black smoke at startup.