Evening all,
Just curious about something… I managed to pick up a Morris rocker cover from the National Rally and I’ve replaced Nellie’s chrome one today… I think it looks great! However I’ve noticed that the Morris badge appears to be on the opposite side compared to others I have seen online? Was there a variation in design or has someone had the badge off at some stage and stuck it back on the wrong side?
The cover could only fit one way so pretty sure I’ve not put it on upside down
I would suggest that there are about 10 variations to the 'A' Series rocker cover. You have a later version without the breather. Even though you have the oil separation canister connected to the SU carb I would suggest that you should also have the breather in the top of the rocker cover which is positioned when fitted between the front securing stud and the oil filler. Note the flat top in the area described. You cannot have enough venting of the crankcase with a 'A' Series.
You appear to have a stick on Morris badge which makes me think that the rocker cover has been refurbished. The badge should be on the offside of the rocker cover.
Last edited by philthehill on Sat Jul 25, 2026 7:54 pm, edited 1 time in total.
philthehill wrote: ↑Sat Jul 25, 2026 7:49 pm
I would suggest that there are about 10 variations to the 'A' Series rocker cover. You have a later version without the breather. You should have the breather in the top of the rocker cover which is positioned when fitted between the front securing stud and the oil filler. Note the flat top in the area described.
You appear to have a stick on Morris badge which makes me think that the rocker cover has been refurbished. The badge should be on the offside of the rocker cover.
Aah thanks that makes sense. Nellie had her original engine switched out for another a series way back in the 70s, so although she’s an early car her engine will be newer… so someone put the badge in the wrong place… brilliant
I too have the same breather system as mrs smith, with plain rocker cover ( I take note of your suggestion Phil ) However I have a manifold that would allow the fitment of a PCV valve, would this be a worthwhile addition to the breathing ?
Les
Having the two means of breathing i.e. the PCV and carb vent working at the same time would in my opinion upset the mixture so much that you would have problems getting the engine to run correctly. You can have either the PCV valve or vent to the carb but not both.
To maximise crankcase/engine breathing you need to have the top of the engine also vented and not just rely on having all of the crankcase breathing exit through the oil separation canister to the carb. A 'T' piece in the pipe from the canister to the carb and a vent in the top of the rocker cover connected to the 'T' piece would maximise the crankcase breathing. Or have the canister and rocker cover connected to a PCV valve.
The canister needs to be cleaned out on a regular basis and having the split canister (use search facility for details) allows for the cleaning. As you will know the canister gets very choked with crud and can be ineffective with use especially as the canisters are now of a age where they are likely to be fouled and breathing ineffective. Below is the removed contents of a canister and not a pretty sight.
Breather canister crud.JPG (249.15 KiB) Viewed 396 times
