Oil out of the breather

[peter2]

Hi,

my Super Major started spilling oil out of the breather on the timing cover. I learned from older posts here that

1. hard work for her may help, so I disced an hour on a friends field.
2. the air filter sucks air from the motor body.
3. the breather normally contains some wool or mesh.

I opened the breather and found nothing in. Someone must have opened it before and cleaned it out.
I filled the breather with a stripe from an old towel, but don't know, how tight the filling should be. Actually it's (I think) very tight. Might that come to a problem if there's not enough air coming through?
Is the breather sealed on the top? Due to the former opening the cover has a small gap around. Maybe I simply have to close that gap?

The metal pipe at the air filter body that comes from the valve cover is not completely closed, so air can get in from the outside and not only from the motor. Is that normal?
I taped it as good as possible to make it tight.

Next step will be a plastic bottle around the breather to prevent the ventilator blow the oil around the whole tractor ...

Peter

[Pavel]

All engines have to have a system to scavenge and relieve the build-up of pressure inside it which are caused by thermal [heat] expansion and piston ring blow-by. Without this the internal pressure would cause serious, and messy, oil loss through gaskets and oil seals. The Major achieves this with a SEALED pipe from the rocker cover to the air cleaner where the flow of air through the air cleaner causes a slight pressure drop, or vacuum, in the pipe, much like the air flow through a carburettor that sucks out fuel from its main jet in the process. Obviously the sealed pipe should not be blocked with carbon -- which becomes much more likely as the piston rings and cylinder walls wear.
The timing chain chest is a semi-sealed compartment and therefore needs its own breather -- the small oil cleaner with the loose fitting cover on top of the chest. The inside is filled with coiled metal strips, much like a metal pot scourer, but with each strip about a millimetre wide. This is so that the oil in the vapour will condense on the coil strips and drip back inside instead of plastering it all over your nice shiny paint work.

Pavel

[Brian]

Sorry Pavel, got to disagree with some of what you said

The breather on the timing cover is an air intake for the engine to breath. As you say, the pipe on the air cleaner should be sealed and this should draw air in through the breather on the timing cover exactly as you say, like a carburettor. On new engines that timing cover breather had to be serviced and a small amount of oil put in it to trap dirt just like the air cleaner because of the way air was flowing in the engine. It was quite common in dusty conditions to find an appreciable amount of soil in there when you took it apart. As the engine wears compression leaks past the rings and becomes greater than the air flow caused by the air cleaner/valve cover pipe can handle, then oil starts to blow out of the breather on the timing cover.

In the timing cover, just under that breather there should be a cone shaped deflector on the auxiliary drive gear. This can break off or not be replaced when the engine has been stripped down. If it is left off the timing gears will throw oil out of the breather.

I would agree however that the most likely cause of the problem is a worn engine or one that has not bedded in.

[county654]

If the reason is the breather, it is available at agriline.

[Pavel]

Thank you Brian for the very courteous way of correcting me. You have also explained why my Major exhaled any oil I placed in it as per service instructions. Obviously the rings are worn.
Interestingly I once owned a 1939 Wolesley 8 that had one of these canisters on the timing cover and the 'experts' gave me the answer that I stated in my post -- thinking the Major had a similar set-up. We live and learn.

Pavel

[Brian]

No problem Pavel, it is something that is not common knowledge I have found. Most people think it is to let fumes out rather than an intake point.

Are you going to be outside your place waving as we pass over in 7 weeks time?

[Pavel]

Was that last question for me, Brian? If so give me a heads up -- I'll be wherever.

Pavel

[Brian]

Hi Pavel,
Yes, we should be crossing the coast on the way to Melbourne from England on the evening of October 6th. We arrive in Melbourne about 10.30pm. You will know our plane, it will be the one going up and down as two excited people bounce in their seats.

[Pavel]

Sadly the flight path, Uk to Melbourne via Perth, is 350 clicks north of us so the hay bales in the paddock reading 'Welcome to Oz' [ah la Tour de France] would be pointless. Still I, like most of us on your return, will look forward to your report and pics.

Pavel