Triumph Repair: Triumph car ignition system, spark plug leads, car ignition system


Question
I have a 1975 Triumph 2.5 Mk2.Automatic. suddenly it stopped firing on cyl's 1 & 3, I replaced the spark plug leads and managed to get #3 firnng again, but even with a brand new plug and lead on #1 it will not fire, I haven't done a compression test yet as it also has a faulty starter motor which I will be replacing very soon. hope you can shed some light on this problem for me...Thank you.   Len.

Answer
Len,the cap might have a crack in it... you usually can't see them so i'd replace it. take the plug out and put the wire back on it. touch the end of the plug to a good ground and crank the engine over. you should be able to see the plug firing then. If it dosen't and it's the only one then the problem might be the distributor itself. sometimes the shaft wears out and can't make a high point to open the points! If you see a spark then the next thing is go ahead with a compression check.the cylinder could have a problem like a bad valve or a cracked head. or the head gasket itself. the head gasket could show the oil and water sort ot mixing. we don't want any of those last 3!!!!!Dave