m0ss4yy Posted December 22, 2009 Share Posted December 22, 2009 Ok so my car wouldnt start and was completely overfueling, it just wasnt sparking. The brand new points in there were duds, so i put the old ones back in and then it sparked at the points. Tried to start it, plugs got wet and shit again, so i cleaned them, tried again, same result. So im thinking it probably has to be the leads, there is this white looking shit on them, it looks like maybe the insulation shit or something is damaged? Im wondering if theres a way to test the 5 ht leads with a multimeter or something similar? Its really annoying cause it probably something stupid like leads. Helps please Quote Link to comment Share on other sites More sharing options...
Mike-e Posted December 22, 2009 Share Posted December 22, 2009 yep. set the multimeter to check for resistance then check the resistance value against the manufacturers specs. to check for arcing place one hand on batt negative then rub hand along the length of the lead with vehicle going. note which lead shocked you as you fart and pass out. Quote Link to comment Share on other sites More sharing options...
Beaver Posted December 22, 2009 Share Posted December 22, 2009 note which lead shocked you as you fart and pass out. thats the most imporant part, otherwise just do it again Quote Link to comment Share on other sites More sharing options...
m0ss4yy Posted December 22, 2009 Author Share Posted December 22, 2009 If i turned the starter over with the lead a few mm away from the block or something and it sparked, would that indicate they're sweet, or would I still needa check the resistance? Cause using a multimeter is really low voltage, higher voltage heats the leads, and changes the properties dramatically. what I like to do, to check my spark plugs are sweet, is wedge my eyelid between the gap, and give it a fire, works nicely Quote Link to comment Share on other sites More sharing options...
thegreatestben Posted December 22, 2009 Share Posted December 22, 2009 Ffffffuuuuuu... If you just check the resistances of all the leads, their resistances will be proportionate to their length. If all your leads are about the same resistance give or take depending on length then you know they're either: A) all sweet or all fucked If your points are fucking out maybe worth changing the condensor too Quote Link to comment Share on other sites More sharing options...
m0ss4yy Posted December 22, 2009 Author Share Posted December 22, 2009 I changed the condensor when i put the other points in, same with rotor and cap. Three of the leads are about the same length, and 1 is a short one. But theres this shit on them, looks like white sorta stretch marks, thats why im thinking they could be fucked. (bent or something in the past??) they all have some white marking in at least one place. unless its the coil ht lead not doing its job? Quote Link to comment Share on other sites More sharing options...
Beaver Posted December 22, 2009 Share Posted December 22, 2009 do what tgb said. its highly unlikly they are all fucked so yeh Quote Link to comment Share on other sites More sharing options...
m0ss4yy Posted December 22, 2009 Author Share Posted December 22, 2009 Just with a random normal multimeter? Quote Link to comment Share on other sites More sharing options...
Beaver Posted December 22, 2009 Share Posted December 22, 2009 yep, just set it on resistance and bobs your uncle Quote Link to comment Share on other sites More sharing options...
thegreatestben Posted December 22, 2009 Share Posted December 22, 2009 http://lmgtfy.com/?q=checking+ignition+lead+resistance Quote Link to comment Share on other sites More sharing options...
m0ss4yy Posted December 22, 2009 Author Share Posted December 22, 2009 If they're all the same.. should they have basically no resistance at all yeah? Quote Link to comment Share on other sites More sharing options...
toyabusa Posted December 22, 2009 Share Posted December 22, 2009 also as you check them bend them and move them around etc, they sometimes may only show a fault in a certain position they should be around 2K ohms per 100mm depending on type etc Quote Link to comment Share on other sites More sharing options...
KKtrips Posted December 22, 2009 Share Posted December 22, 2009 Since I was an apprentice working on horse drawn buggies with points ignition, the rule I always followed for checking resistance of HT leads is 15000 ohm's per ft of lead - its nothing to do with measuring voltage. Much above that and you should replace them. I dare you to measure voltage on the HT side with a multimeter... A very agricultural way to check them is to open the bonnet and get someone to load the engine (make sure the handbrake is on and wheels are well chocked) and turn the lights off in the workshop so its dark - you may be able to see the HT spark going to ground which is a definite fail.... (if you don't see a spark - it doesnt necessarily mean they are OK) Quote Link to comment Share on other sites More sharing options...
m0ss4yy Posted December 22, 2009 Author Share Posted December 22, 2009 Yeah heard that one before. Looking for electric streaks or something huh? I have to get a battery for my multimeter first Quote Link to comment Share on other sites More sharing options...
m0ss4yy Posted December 23, 2009 Author Share Posted December 23, 2009 Checked leads on 20k on the multimeter. Lead 1 - (380mm) gave me 8.74 = 2300 ohms/100mm. Lead 3 - (280mm) gave me 6.14 = 2192.9 ohms/100mm. Lead 4 - (300mm) gave me 5.74 = 1913.3 ohms/100mm. Lead 2 - (280mm) gave me 5.78 = 2064.3 ohms/100mm. Coil lead - (270mm) gave me 6.28 = 2325.9 ohms/100mm. So based on this: they should be around 2K ohms per 100mm depending on type etc The leads seem to be fine? Quote Link to comment Share on other sites More sharing options...
Toucan Posted December 23, 2009 Share Posted December 23, 2009 Ignition system is only as strong as its weakest part, you have replaced points/condensor/rotor/cap/plugs. Buy new leads. Quote Link to comment Share on other sites More sharing options...
m0ss4yy Posted December 23, 2009 Author Share Posted December 23, 2009 New plugs and leads is the go for now. (plugs have only done about 100km though) Quote Link to comment Share on other sites More sharing options...
KKtrips Posted December 23, 2009 Share Posted December 23, 2009 Checked leads on 20k on the multimeter.Lead 1 - (380mm) gave me 8.74 = 2300 ohms/100mm. Lead 3 - (280mm) gave me 6.14 = 2192.9 ohms/100mm. Lead 4 - (300mm) gave me 5.74 = 1913.3 ohms/100mm. Lead 2 - (280mm) gave me 5.78 = 2064.3 ohms/100mm. Coil lead - (270mm) gave me 6.28 = 2325.9 ohms/100mm. So based on this: they should be around 2K ohms per 100mm depending on type etc The leads seem to be fine? Those seem absolutely grouse to me.. I wouldn't suspect your leads - perhaps dist cap or rotor is the next place to check. Remove the cap and take the coil HT out of the centre of the cap - hold it approx 5-10mm above the centre of the rotor and get someone to crank the engine - if you see a spark jump the gap between the lead and rotor - replace the rotor. if not - the rotor should be OK With the distributor cap, there is not much you can test except checking for obvious damage/cracks and continuity of the conductors, if it looks old and filthy - just replace it - costs bugger all and is good insurance anyway. Quote Link to comment Share on other sites More sharing options...
m0ss4yy Posted December 23, 2009 Author Share Posted December 23, 2009 With the distributor cap, there is not much you can test except checking for obvious damage/cracks and continuity of the conductors, if it looks old and filthy - just replace it - costs bugger all and is good insurance anyway. Both rotor and cap are brand new. Could test the rotor by that method ^ then if thats sweet, test cap by taking off coil lead from the dizzy, and hold it next to the block and see if that sparks, if it does, narrowed down to the cap, carbon point in the cap. Should be sweet though, its new?! Mind you, the points were too (which they have already sent me a free set) Quote Link to comment Share on other sites More sharing options...
KKtrips Posted December 23, 2009 Share Posted December 23, 2009 With the distributor cap, there is not much you can test except checking for obvious damage/cracks and continuity of the conductors, if it looks old and filthy - just replace it - costs bugger all and is good insurance anyway. Both rotor and cap are brand new. Could test the rotor by that method ^ then if thats sweet, test cap by taking off coil lead from the dizzy, and hold it next to the block and see if that sparks, if it does, narrowed down to the cap, carbon point in the cap. Should be sweet though, its new?! Mind you, the points were too (which they have already sent me a free set) If they are brand new they will be OK - unless you have dropped them. Also your comment about testing the cap by holding coil next to the block confuses the fuck outta me. It makes zero sense.. Quote Link to comment Share on other sites More sharing options...
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