M20 Rocker cover Breather

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hannaconner
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M20 Rocker cover Breather

Post by hannaconner »

I am now captain paranoid about making sure everything in my rebuilt engine is clean. I haven't stripped the old engine yet but will be using the head and ancillaries to go on my rebuilt short motor. The oil I drained from the old engine was nasty, looked like metallic paint, upon removing the sump it had lots of grey metallic sludge. I went out and bought a parts washer today so cleaning the head etc should be fairly straight forward.

How do I clean the inside of the rocker cover? there is a riveted plate that covers what I assume is the gauze which constitutes the breather. I'm imagining 38 years worth of oily deposits and accumulated combustion crud will be inside. I've rinsed it with parafin over and over but no matter how many times I do it there's always more crud coming out.


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uwbuurman
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Re: M20 Rocker cover Breather

Post by uwbuurman »

Thats needs to be chemicaly cleaned. Industrial powerwasher or something like that,. I just brought one of mine to a engine overhaul company, they just toss it in the washingmachine with other engine components.

Dont sandblast it, it is almost impossible to get all the sand out, with all risks of engine damage if it gets in the oil.
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1978 BMW 323i
1980 BMW 528i maior restitutio
1987 BMW 325iA cabriolet
2015 BMW 320dA touring xDrive High Executive ///Msport
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