Morris Minor Owners Club

While having a fiddle with the mixture (which is still a bit too rich despite the nut being right up) I decided to replace the Oil Bath style air cleaner with a sports filter I had lying around. I thought a better air flow might help the mixture, not to mention the Oil Bath type gets in the way of everything! I had to leave the bracket on the rocker cover to hold the throttle cable.

Running OK with the Sports filter but a but noisier. What does everyone think of different type filters? What is the best sort to use?

I very much doubt it will make any difference to your 803 engine. And as you see, much more noise. I thought the idea with old Minors like yours was to keep them as original as possible? If you want to go faster then fit a larger capacity engine.

It's not about going faster - just trying to get the mixture right. Plus the Oil Bath cleaner makes access to things difficult. Will prob replace it but interested to know if anyone has thoughts on benefits or otherwise of different types of cleaners.

There is no doubt it gives slightly better air flow at FULL throttle, but how often do you drive at full throttle? It is much noisier, and if you drive in dusty air conditions I suggest the oil bath filter will probably do a better job of keeping dust away from the engine. Your mixture problems are down to float level/needle valve, not lack of air through the filter!

The oil bath filter was fitted to export Minors and Post Office vans. If you have tried setting the mixture with the filter on and off and it is still rich then either the needle or jet or both are worn. On a worn H1 carb I had to adjust the needle so that the shoulder was raised out of the piston so that it ran weak enough on tickover. As has been said earlier all the needles of that size have almost, not exactly the same diameter at tickover so any 090 needle should give almost the same results. The difference between needles will only become apparent when the engine is revved

In another thread - the float chamber has been found to be overflowing..........

David53 wrote:What is the best sort to use?

The best filter is the oil bath type IMHO

Yes Roy, I did have a float chamber problem but fixed that yesterday - replaced the needle valve and no longer spurting from top of chamber. Can you remind me how to check if the level is correct? From memory you take off bell chamber and sight the jet but can't remember what I'm looking for.

Assuming Float level is correct, and air cleaner is not going to make any difference is there any other reason I would have too rich a mixture at idle? Nut is screwed all the way up and lifting the pin gives a slight increase in revs if I lift slightly. Lifting all the way kills the engine but I think this is normal.