Morris Minor Owners Club

High everyone,
I have just had a new stainless exhaust built and fitted to my minor,i also fitted an lcb manifold which i have taken from my other mog. Of course i had to put an inlet manifold on as well and the inlet was a 4 stud fixing,however the carb is an inch and a half with a two stud fixing! I took out two studs and fixed the carb on with the relevent new gaskets. The inlet had the vacuum plug blanked off as i have no servo. However the car runs uneven now,can anybody tell me why please??

Regards Andy

Hi and welcome along
What needle is in the carb, I guess the carb is a HS4.

Make sure there are no air leaks at the carb/manifold junction and at the manifold/head junction. Is the vacuum advance connected to the dizzy ? Is the engine otherwise standard? I would fit an AAU needle..

Hi,
The engine is fairly standard except for oversized valves and inch and a half carb. On the inlet manifold (water heated) there is a vacuum take off which i have blanked off as the vacuum is taken off the carb. Interesting to note though,the engine was running perfect before fitting lcb and the new larger bore exhaust??
Andy

As long as the vacuum is connected - and working at the dizzy? Have you checked? What size valves in the head - indeed -what head? Don't connect the water heating!!! And yes - the LCB is designed for long period cams, and can actually lose power on a 'standard' engine. Still suggest an AAU needle - or perhaps an AAA - although it will burn more fuel.

Hi,
Sorry for late reply as i work away some weeks!....the head is a standard 1098 with oversize valves(not sure exactly what size) why do you say do not connect water heating? all i have done is fit lcb and inlet and van was runnig fine beforehand.
Thanks

Because you want the charge to go in as cold as possible, ' Twin carbs ' don't have a heated manifold (pretty much their only 'advantage')....... so why should the single be heated ?

Thanks very much for your help,might have to go back to original manifold!
regards Andy

As long as it's all airtight - no leaks , it should be good. Double check that in all the fuss - the plug leads haven't been mixed up...... 1342 anticlock round the dizzy cap.

Thanks again