On engines earlier than the Mini A-aeries, such as the Dodge flat head six, they had a breather oil cap which had a permanent oil-soaked filter material in it. Down below they had a steel tube coming out of the crank case and hanging down into the air stream under the car. THe flow of air would generate a Venturi effect on the tube, pulling air through the engine, It also pulled some oil mist, resulting in the bottom of the engine and transmission being coated in tarry mess. You could assess the engine's relative condition by how much smoke puffed out the draft tube at idle.

 

The oil cap worked like the oil bath air cleaner sitting on the carb. It had a permanent metal mesh filter and the bottom of the air cleaner had an oil pan of sorts containing engine oil that would keep the mesh coated in oil. 

If you have the stock air filter housing you may find that the hose connection there does not really go into the housing, only on to it. There should be a hose going from that to the rocker cover. Then a hose from tappet chest cover to ground. Theory being that the air is drawn from close to the filter housing thru the engine and out the tappet chest to ground.

Hello everyone

another question

1963 850, all standard.

 

when i pulled the car to bits years ago there were three breather pipe outlets

 

1 was on the air filter housing  - this wasn't connected to anything

 

2 was on the rocker cover  - this also wasn't connected to anything

 

3 was on the tappet chest cover - this was simply a rubber tube that "vented" to the ground

 

 

when i looked at how to set it up at rebuild time i connected all three of these outlets  to each other using a three way plastic tube fitting. therefore the air filter outlet had a rubber pipe connected to the three way pipe connector, which in turn connected to the tappet cover outlet and the rocker cover outlet. 

 

Q is this correct?

 

 I assume that the airfilter connection acts as a vacuum to vent excess pressure from the crankcase

 

 

thnx for advice

 

PS i have a small consistent oil leak from the rocker cover gasket at the heater outlet end - is this in any way connected the breather connections?