Rough higher revs

[sansvalo]

Hi, from the beginning I would like to thank you all for your answers on my problems. I done the cherry bomb muffler fitting on the Morris, works well and pretty silent, too. I have also fiddled around the wheel alignment problem, and it helped to make the front wheels more parallel with the tape measure method.

But some time ago I ran into new problem - my Morris started to run very rough in higher revs, being a little shaky and losing power. Runs fine under low load. I reseted the carb mixture, it seemed to help for like 30 mins, and it started to run rough again. Piston is falling down with a click, and the damper thing have correct amount of oil. Other than that, the car revs seems to go up a bit, but sometimes they are normal. I think I shall check the spark plugs if they are not fouled, do I? It might be that one cylinder is not fired up? I think the petrol pump is working ok, as it only ticks once/twice at ignition time. Or is it the coil problem, or rather wiring, as I remember that previous owner shown me that some connections are sometimes pretty wobbly there (I tried to reconnect them). Where shall I start? Thank you for help!

[bmcecosse]

It's NEVER the coil.......... Could be bearings rattling - or pre-ignition, do you hear any 'pinking'. General engine check - valve gaps and compression test, and check the vacuum advance is working - the Ignition timing may be over advanced to compensate for failed vacuum unit.

[MarkyB]

As above, just give it a tune up first, check the condition and gaps on the plugs, set the valve gaps too.

[sansvalo]

How can I check those valve gaps? Do I need special tools for those and plugs, or can I use the calipers? What are the correct spacings in mm? Today I had to go to GP, so I took car for longer trip, and it was ok again. Also I saw this wire: http://puu.sh/7143E.jpg hanging near the coil, it's in very poor shape as well as other wires, should it be connected to the coil or what? There is one free slot. Where can I buy new wires to replace the old ones?

[bmcecosse]

I suspect that wire is for oil pressure warning - or oil filter warning. If you clean it up - what colour is it? Gap for plugs 0.025" (0.65mm) and for valve gaps is 0.015" (0.38mm) and yes - you need 'feeler gauge' strips to measure the gaps properly. Like these.... http://www.ebay.co.uk/itm/DRAPER-18-BLA ... 2586f4b6c5

[sansvalo]

Thank you, I will clean it up tomorrow. I just learned the 9 method on valves gaps, do I count them from front or back of engine looking from front? Shall I set both inlet and outlet for 0.38mm? Or is it different for inlet? Thank you!

[bmcecosse]

Front or back as you wish! But normally from the front on a Minor... Just set the same gap for now at least - it's not critical.