Valve chest breather

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Steve R
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Valve chest breather

Post by Steve R »

I have just bought my first Minor, a 1968 two door with a 1098 engine. The engine runs fine, starts first turn of the key and pulls well with no smoke from the exhaust. It did have a bad oil leak from the rocker gasket when I first got it. I have cured that but have noticed an occasional drip from the valve chest breather pipe when the engine is running. This pipe is a vertical tube pointing at the ground and is not connected to anything.( I cannot see that it should be) Is this normal?
les
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Re: Valve chest breather

Post by les »

Welcome to the forum.
There are different breather arrangements for the Minor, however the type you describe is normal to be open and vent to the ground
philthehill
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Re: Valve chest breather

Post by philthehill »

The pipe described is not connected to anything - it just exits to atmosphere.
The occasional drip of oil is normal especially if the engine has done some mileage.
Make sure that you have the right rocker cover filler cap. The filler cap for your set up is the non breather type.
You could install the valve chest cover with the oil separator which is connected to either the Pollution Control Valve (PCV) which allows fumes to enter the manifold for burning in the combustion chamber - or connected to the carb for the same purpose.
A photo of your engine in the area of the inlet/exhaust manifold (from above) and the breather would be appreciated.
The Morris Minor with engine number prefix 10ME was fitted with the closed circuit breathing system. What is the prefix to your engine number?

Steve R
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Re: Valve chest breather

Post by Steve R »

Thank you so much for your very informative reply. I will take a photo tomorrow and post it. Once again many thanks
Steve R
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Re: Valve chest breather

Post by Steve R »

photo of engine
photo of engine
engine 1.jpg (162.06 KiB) Viewed 312 times
photo of engine
photo of engine
engine2.jpg (148.36 KiB) Viewed 312 times
photo of engine
photo of engine
engine3.jpg (163.44 KiB) Viewed 312 times
philthehill
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Re: Valve chest breather

Post by philthehill »

Thank you for the photos.
The photo I was hoping you would post is the oil filler cap in the rocker cover. A side on photo of the filler cap removed would be appreciated as it would determine as to whether you have a non breather or breathing cap. With the valve chest covers fitted you should have a non breather cap.
You have the right valve chest covers for your 1098cc engine.
The breather pipe could be extended to the same level as the bottom of the sump with a piece of rubber pipe to get the end of the breather pipe into the airstream below the car. The air stream will suck any fumes out of the engine.

Steve R
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Re: Valve chest breather

Post by Steve R »

engine 4.jpg
engine 4.jpg (86.21 KiB) Viewed 283 times
This is the oil filler cap fitted. Once again many thanks for your advice. Steve
philthehill
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Re: Valve chest breather

Post by philthehill »

Thank you for the photo.
You have the correct non breather oil filler cap.
So that you know the difference - here is a vented cap.
oil filler cap.JPG
oil filler cap.JPG (966.18 KiB) Viewed 278 times
The cap has a gauze centre that allows air to enter through it to the engine, the air collects the engine fumes, then passes out of the engine via either the Pollution Control Valve (PCV) or carb for to be consumed in the combustion process.

Steve R
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Re: Valve chest breather

Post by Steve R »

That clarifies things nicely, and it appears normal that there may be the odd drip from the breather tube. To stop the oil collecting at the joint between the sump and the block I will extend the tube to the bottom of the sump.

First time I have posted and found the forum really useful. Thanks
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