M20 Rocker cover Breather/Gauze Cleaning

[e21Keith]

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.

No way of getting to this, but how do I make sure it's clean?

[Wilmo]

Take the boat to the Netherlands, go to the nearest Wibra and buy this:



It is enough to put the bottle near the dirty parts, about 30cm is enough, and all grease will disappear like snow in the sun.


Or maybe the stuff is available elsewhere as well, I saw it on Amazon for instance. And of course, spray it on

[uwbuurman]

If you want to do a really good job, that I suggest taking it to a decent overhaulcompany. They have professional industrial washers. Toss it in, set it to wash for half an hour and it comes out like new. Quick coat of paint on top and you'll have the icing on the cake that your new engine deserves.

[Thegs]

[e21Keith]

I took the rocker cover to the machine shop today to ask them to put it in their tank, their recommendation was not to do this as it would possibly create pockets of sludge which would be contaminated by the cleaning chemicals and could degrade the oil. Their recommendation was to drill off the rivets holding the plate inside and have a look, so I thought I'd try this on a spare cover first. There is no gauze inside it's just a zig-zag path through the cover and yes it was full of crud.
So how best to re-fix the plate inside the cover, rivets, self tappers? obviously needs to be something that wont come loose

[Wilmo]

Come on, they are looking for nails on low water (Dutch saying). Don’t open it since you will probably create a ton of different problems.

Last weekend I cleaned my bike chain with petrol and Dasty and when there is something with contained spaces, it is a chain. After soaking and rinsing the thing was completely clean. Buy some of the stuff and see the magic on the accessible dirt and extrapolate it to the container volumes.

[uwbuurman]

Yeah, agree. Hose it down good, use air, use cleaner that evaporated in to air, like brake cleaner. Don't open it up. If you are affraid of getting residu into the oil, then after cleaning, you just put it upside down and fill it with oil, leave it for a day. Fluss it. Done.

[Jeroen]

Think I'd give it a lot of Dasty and then use the pressure washer to clean it out. Without removing the plate. Then leave to dry in different positions for a couple of days.

[e21Keith]

I had already soaked the rocker cover in paraffin for 2 weeks prior to the first engine rebuild, cleaning and re-flushing over and over, each time there was more debris coming out, lumps and flakes of it. I tried oven cleaner, jet washing, paint thinner, you name it. Even after this it was still full of crud, some soft, some hard.
My autism tells me that if I can't see it's clean and there is still crud coming out then its still not clean inside and that's not good for my engine.

[Jeroen]

if it's that bad yeah then I can imagine how you feel about leaving the plate in place!

[uwbuurman]

In my mind just keep flushing until nothing comes out anymore

[e21Keith]

Doesn't matter how much flushing it never came out clean, always bits of debris, so as I have two covers I've opened one up to clean and I will refit the plate with screws/self tappers/rivets, to be decided. Then I'll decide which one to fit.

[BertjeConti]

I've used the most common degreaser available in the Netherlands, which is "Dasty", for cleaning my rocker cover (and the whole inner of the engine block and head) by soaking it with the degreaser for a while and then rinse it with hot water. Repeated the process a few times, and that cleaned the labyrint completely.

Do not take off the plate, there is no way to secure it back in place safely.