Slight misfire from one exhaust

Post by **toolmanchris** » Wed Jul 11, 2018 12:34 pm

When my Essex engine is ticking over once warmed up I get a slight misfire from the offside exhaust. Nothing major but every so often its as if a cylinder misfires then back to normal again. Other bank is fine.
Plugs and leads are fairly new and the carb is also (DGAS)
Adjusting the idle screw on that side seems to make no difference.

I have checked for air leaks and nothing identified however I did notice a slight exhaust leak between the manifod and the downpipe could this be the culprit perhaps?

Thanks

Post by **philhoward** » Wed Jul 11, 2018 12:41 pm

Seems to be something some cars suffer with - a slight "is it?" missfire from one bank.

Valve clearances OK? Dizzy cap? There's some questionable ignition parts floating around nowadays, sadly - the joys of making parts from 50 year old tooling and getting small batches made by the lowest (only) bidder

- not a fault of any supplier as that's all you can get now (unless you happen across some NOS bits).

Post by **toolmanchris** » Wed Jul 11, 2018 12:50 pm

Valves are a bit tappety on that bank Phil but I cant seem to adjust the noise out, dont know if the cam might be worn. I did notice that one of the valve guides on that bank at the front has been welded back together so I wondered if the timing wheel had gone bang in the past and the pushrods had broken it.
I checked all of them when I had it converted to unleaded and they were straight enough though.

Post by **mattscimmy** » Mon Jul 23, 2018 12:59 pm

I had this on my 6a, a new ballast resistor fixed it. Lots of other possible culprits possible. Usually the last one you think of.

Post by **peter freeman** » Mon Jul 23, 2018 3:32 pm

Don't assume that a new plug is always good - they are not.