Hi all

I purchased my Mk 1 S with an alloy rocker cover with a vent pipe near the filler cap connected to the airbox.

I was looking to replace it with a tin one but am puzzled as to whether I need a vent pipe.

I am aware of the cut outs for the head bolts so do I search for one with the cut outs and a vent pipe?

Maybe someone out there has the one I need that they are happy to sell?

I go to various show and shines and talk to mini owners and walk away further puzzled but I guess that part of the intrigue of minis.

Thanks in advance.

Have a look through the photos on here, the rocker covers were plain tin with no breather. The breather from the tappet cover went to the PCV
http://classicregister.com/id-pages/how ... oper-s-mk1

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Here is a period photo from a 1967 S that I like to refer to.

They never vented to the airbox. Rocker cover had no vent pipe.



The MK1 S had 2 types of rocker covers. The first had a riveted Morris and Patents plate from 1965 to 1966.




The second had the Morris and Hot run tested stickers from 1967 to 1969. I am not 100% of the exact change over.

Thanks GTO you are always a wealth of knowledge.

You can see the blank behind the oil filler on both rockers which is where my pipe is on the alloy cover.

I know now what to look for- just hate the alloy.

Thank you again

The 1970 MK2 S had the same except they used just one Hot run sticker at the front. So it doesn't matter which one you use if you are going to respray and re-sticker it. Here is a photo borrowed from Winabbey.



One thing to look out for is the embossed Mowog Aussie map. They were only fitted to Aussie motors - not the Cooper S. My car has this type fitted by the previous owner and I have been too lazy to change it.

Did the Clubman Gt have the same as the Mk2?

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1963 Morris 850 Smoke Grey
1963 Morris 850 Shadow Blue
1965 Morris Mini Smooth Van
1966 Morris Mini Van
1969 Morris Mini Deluxe Resto
5/72 Clubman Gt

I am not an expert on the GT so maybe someone else will jump in.

I believe the early GT engines had the same as the MK2 S and the later GT engines had the embossed Mowog Aussie Map.

Here are photos of 2 early and 1 late and you can just make out the embossed rocker cover on the late one.

The rocker cover you are after without the breather came with the British built engines. like the Cooper S and 998 Auto. They each had a PCV, so didn't need a rocker cover breather. They differ only slightly from each other with the clearance for the extra bolts on the Cooper S.

It can be simple enough to find a 998 Auto rocker cover and file the reliefs yourself for the head nut/bolt. Its only a small crescent filed for each.

https://www.ebay.ie/itm/CLASSIC-MINI-10 ... 1a439d74eb

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SooperDooperMiniCooperExpertEngineering

All garage work involves equal measures of enthusiasm, ingenuity and a fair degree of irresponsibility.

On the NO breather rocker covers, was the oil filler cap vented?. Is there any correlation to vented /unvented caps and the rest of the breathing arrangements? Also to Tomtax, your original question regarding changing,,,, are you looking at:
need ( eg 1.5 RRockers won't fit under existing)
Being period authentic
simply preference or
performance, as i daresay the answers could be different . cheers

Yes the cars with PCV valve or carb vac ports ran the breather cap. But a sealed cap worked fine on my 1412 stroker.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

You don't really need a vented cap or rocker cover when you have a CCV valve/system.
Virtually all modern engines have a CCV system and the engine is sealed - ie no external breathers.
They rely on air being drawn into the engine past the crankshaft oil seals for the CCV system.
It also helps minimize oil leaks from the seals.

RonR

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68 build Mk1 Cooper S
72 Clubman GT project. Total restoration required

A hijack question re. rocker covers:
Was a thick spacer washer always fitted between the rocker cover cap nut and the cup washer that covered the rubber grommet?

Yes, AFAIK, Bill.

To FNQ

Yes just after period authentic. I just have a preference for unmolested mini's. Mind you what is really authentic is always questionable given the lack of Mini records.

Regards

Tom