plenty of spark but????

[bleddyn]

hi everyone, me again. have tried everything that has been suggested, all electrics working,have taken plugs out, but them back into leads, have a brilliant blue spark on all plugs,have double checked firing order, by turning over and waiting for blow back on each plug, and firing order correct,have removed old petrol from carb, cleaned out, and replaced with fresh petrol to carb, dont know enough about carb to pull apart, strip down etc,have had suggestions about timing being out, but how do i check without having being able to start her up, have already had one of these mobile mechanics out,and still no success, getting deparate now,and plenty of smell of petrol coming through on plugs after turning over, anymore suggestions, am 17 miles from Swansea if anyone fancies having a go, willing to pay,no problem, but need someone who knows moggies,not mordern mechanic who thinks he knows, if you understand what i mean, all suggestions really appreciated

[bmcecosse]

If there really IS a good spark - and petrol - it should go, provided there is some compression. Have you poured some petrol down the carb and tried that ? Otherwise - try a fresh set of plugs - they aren't NGK by any chance ????

[bleddyn]

brand new set of plugs,in fact brand new everything, have emptied float chamber and cleaned out and filled with new petrol, when you say poured new protrol down carb, can you give me more info, thanks

[Dean]

I think you have done exactly what bmc requested regarding refilling the carb. I'm getting a bit stumped myself now, if everything is correct it should start.

bmc mentions compression.. have you a means of testing the compression.. ie a compression tester? This will tell you if there is anything wrong with the valves or pistons.

If asking for a mechanic, just mention old 'A' series engine with carb then give year of car. Many proper mechanical apprentices should have trained on these engines...


Is there a local club member that could help this guy out????

[bleddyn]

hi, do you think i should take the fuel line of carb and see if there is blockage or something or prehaps gunge, i noticed when cleaning float chamber, some dark deposit into both corners below outlet, although smell of petrol on plugs after cranking, they wer'nt wet ,and it was'nt a strong smell

[bleddyn]

hi, do you think i should take the fuel line of carb and see if there is blockage or something or prehaps gunge, i noticed when cleaning float chamber, some dark deposit into both corners below outlet, although smell of petrol on plugs after cranking, they wer'nt wet ,and it was'nt a strong smell

[bmcecosse]

Just tip a good 2 X egg-cup full of petrol down the mouth of the carb. Crank it - it should fire and run for a few seconds at least. If it does - then the problem is fuel supply - if it still doesn't start then the sparks are either insufficient - or at the wrong time!

[Dean]

Is there a safe way to hold the starting handle when cracking? I have been told it may break your thumb if held in a certain way when cranking?

[bmcecosse]

Indeed - you must NOT curl your thumb around the handle - keep it sticking straight out. Just hold with the 4 normal fingers - so if the engine 'kicks back' the handle will jump out of your hand.

[bleddyn]

hi, put 2 capfulls of petrol direct down carb as suggested,and you were spot on,started and after 10 seconds cut out, so we have strippped carb down,cleaned everything out put all back together, and yahoo, starts like a dream, thanks again and have a nice christmas

[Dean]

Well done!!!! Fantastic news.... just in time for a nice cold beer!

[bmcecosse]

Great success. Merry Christmas!

[rayofleamington]

hi, put 2 capfulls of petrol direct down carb as suggested

well done - When i mentioned it on the other thread I didn't really know what 'measurement' to give. I've only ever given it a 'heavy splash from the petrol can'.
Once (on a Modern) I was desperate and didn't have a can of fuel so I sprayed lighter fuel into the inlet plenum - this worked just as well as petrol! That one turned out to be a failed fuel pump.