Bowie69 Posted January 5, 2012 Share Posted January 5, 2012 A mate has been running Megajolt for just over a year now, very pleased with it, and a very good increase in economy at the same time, due to being able to run two ignition maps. However, as he had a lovely set of Magnecor HT leads (not my choice I assure you) connected to his Dizzy, I reused these and instead of Generation 1 coil packs, I used the later 'normal' terminal coil pack, which you can connect regular HT ends to with no problems, as long as they have internal grips as well as the normal 'cage' on the end of them. A couple had come loose at some point and the result was completely burnt through terminals on the end of the leads from the arcing -I could have just got Magnecor to repair them, but instead after a PM to Nige, he suggested a mate of his had managed to get 10mm Magnecors through his 'Coil Pack Ignition Lead Ends Kit', so thought it worth a try, especially as I have converted 8mm leads before with no problems.... This will be a 2-part post, as I haven't fitted the terminals yet(!), but for starters lets get the boot on the leads Take one old lead, with a possibly burnt through terminal: Cut the end off with a pair of sharp wire cutters, make sure the end of the outer bit in particular is tidy, otherwise it will snag on the way into the boot: Clean the lead throughoughly, at least the first 6 inches, any dirt will make the lead stick in the boot, and any lube with be wasted. For all cleaning and lube I ignored Nige's advice ( ) and went with some bike lube I had kicking around, GT85, and it worked bloody well: Next job is to find some strong twine, very strong in my case due to the thickness of the HT lead... I found some builders lines (for marking out foundations, block work etc) and seemed to do the job well. Tie this in a knot around the HT lead, make sure you use one which is a 'slip' knot, as this allows the loop to self tighten around the lead when you pull on it. I used a two-half-hitches knot and it worked very nicely. Trim some of the excess off, not too much otherwise the knot may pull through and come undone: Feed the end of the twine through the boot from the narrow end : Now the first tricky bit, feeding the lead into the boot, put a bit of lube in the narrow end of the boot, and on the end of the lead, slip the lead into the end of the boot, making sure the outer silicon bit of the lead goes in nicely, and nothing left outside. Only push it in about 5mm (1/4" for old fogies!) as there's not enough lube to go any further and it will just get jammed. Now it is in this far, squirt LOADS of lube from the wide end of the plug lead, and cover the lead for about 6" with lube at the same time, now, as they say, it is time to start pushing. Keep the loop of twine out of the way for the moment, you don't need it yet. Push the lead in with a twisting motion, making sure you don't ruck up the lead outer, which can cause snagging. At the FIRST sign of progress slowing, stop and re-lube from both ends. Once you have done this you should be able to see the end of the lead from the with end of the boot, or at least be an inch into the boot. Now the tricky bit (hence no photo!), getting the lead round the bend; this is where the twine comes in... lube EVERYTHING again, and start pulling -use a rag around your hand to stop it from cutting into your flesh too much. It will take some force to move, especially with 10mm leads, but will go through in the end, pulling the wide end of the boot to straighten the bend as much as possible really helps. Eventually it will look like this: At this point you can trim and fit the terminals (tomorrow's job, once the crimper arrives) and then push/pull it back through the boot, I can't do this yet, so I'll just show off with a completed set of 8 Couple of other points, if it won't go, or the twine breaks, or the knot comes undone or for some other reason you have to start again, don't despair, as the boots have now had a good stretching the next time will be a piece of cake. Keep metal tools away from it, as you will bugger up the lead outer, or the boot, or both. Using this method and some practice I got it down to about 5 minutes per lead, taking my time, making sure I didn't arse it up Will post tomorrow once I have the terminals fitted up Pete. Quote Link to comment Share on other sites More sharing options...
TheRecklessEngineer Posted January 5, 2012 Share Posted January 5, 2012 Can I vote this to the tech archive when complete? I've done this too - it's an absolute pig, but looks awesome when finished - especially when you get the lengths just right and it looks like it came out the factory. Quote Link to comment Share on other sites More sharing options...
bobtail84 Posted January 5, 2012 Share Posted January 5, 2012 When I put 10mm leads on a nigey boot kit I used silicon spray and they pushed right through no probs. Quote Link to comment Share on other sites More sharing options...
stuck Posted January 5, 2012 Share Posted January 5, 2012 When I did mine I just cut the lead at 45 degrees, lubed it with some Fairy and they went on fine. Edit: "Lubed it with some Fairy" could have phrased that it a better way! Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted January 6, 2012 Author Share Posted January 6, 2012 Well today the crimper hasn't turned up yet... but went back and re-inspected the leads, first thing I noticed was the 4-core nature of these Magnecore leads which means fitting them to the crimp is a little different from normal, the reason being there is just not enough room in the crimp for 4 conductors to be bent over, instead Magnecor have a tang inserted into the end of the cut lead: The long end of the tang is pushed into the end of the lead, in between the 4 conductors, and the short one sits on the outside of the outer part of the lead so it makes contact with the metal of the crimp, and give a good path for conduction. Failure to fit this will cause the spark to jump between the HT lead and the crimp causing it to burn through. Note this is just a piece of scrap lead, hence the insulation missing One other point, I saw a mate and he let me have some industrial 'bumper and engine bay dressing' stuff they use when selling cars, and tried this out this morning by disassembling a lead and refitting, it was VERY VERY VERY slippery, and did make putting it back together a lot easier. I have used aerosol back to black silicon stuff before for other jobs, but it dries more than this stuff, which is not in an aerosol, but a 5l tin, it is REALLY sticky, and slippy. If I was doing it again (and I probably will at some point) I will get some more of this for the job. I put it in a little pot and dunked the whole boot in before fitting, slipped the string over the lead and pulled it straight through with no bother at all. Only thing, I have washed and scrubbed my hands about 4 times now with Fairy and a) They still smell of 'new car scent' b) I can barely type as my hands are slipping off the keys -apologies for any typos Another note... 'normal' 7/8mm leads with just one conductor you would trim the outer insulation to reveal just the black inner core, say 15mm or so, and bend this around the end of the lead before fitting and crimping, so basically the same shape as the tang above. Looks something like this: More to come when the crimp arrives... Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted January 11, 2012 Author Share Posted January 11, 2012 Today..... the crimper arrived, very simple device: The main body is hard plastic, but there is a metal liner to the hard working part, for £10 is was worth a punt, and it did help create some much nicer crimps than I would have been able to with a pair of pliers and a hammer.... here it is in place in the vice -not that you need much force to create the crimp of course. So... let's crimp As I am doing the uber-fat magnecor leads at the moment, after a failed attempt at a crimp, I decided it would be better if I removed the first 10mm of the outer layer of silicon of the lead before crimping. This outer layer is predominantly a waterproofing layer from what I can see, and has very little structural integrity, as it tears just by looking at it -unlike 'normal' leads which have a much firmer outer sheath. So I trimmed it back like this: I removed some fine fibrous woven stuff from the end as well, cuts easily with scissors. Then inserted the tang, this needs to go in the centre of the lead as discussed above, but also needs to make contact with the terminal, so when inserting the tang, put it in the 'top' of the lead. This means that once you have crimped it all up and bent the terminal 90 degrees it should pull through without having to twist the HT lead in the boot. Of course if you are using regular HT leads do as described in my previous post The terminal with tang: Next, insert the terminal into the crimper, pretty obvious which way round it needs to go: Then, as it needs 3 hands, I didn't get a photo, but push the lead into the terminal with the tang(or inner core of HT lead) in the bottom of the crimp and gently tighten the vice. First time I did it the terminal kicked over a bit in the crimper and gave a lopsided crimp, and it continued to do this on subsequent crimps to a greater or less degree, I found the best way in the end was to crimp it and allow the terminal to slip a bit, then pull it out, and twist the HT lead so that when you re-crimp it does the other half. I suspect the problem with the crimper is the terminals are not quite the right design for it, but it has made some very decent crimps, far better than pliers and a hammer!: The terminal has made a VERY good physical connection, so I was confident enough to pull on it quite hard without it coming apart Next thing to do was push the terminals back through the boots, easier said than done though as most of the lube (now last used ~5 days ago...) had dried up. Easiest way to get more in was like this: That's a watchmakers posidrive screwdriver, posidrive to avoid snagging the boots. Dip the screwdrive in the lube and wiggle it in to the boot, to the sort of depth show, then dribble more lube into the gaps made by the screwdriver either side, wiggle it about until you can freely move the whole of the screwdriver around the circumference of the lead, then do it from the other end as well -though clearly you won't need to go as deep. Next thing to do is bend the terminal -no picture of it on a lead as too many hands required, but using a pair of point pliers, bend the terminal to almost 90 degrees at this point here: If you've lubed it all up properly (including the terminal) and the crimp is strong enough, pull the lead back through the boot until the terminal sits in the right place, fit the clippy-hood thing (really obvious how this needs to go, then put them all on the desk for posing: Job done Then for more aesthetic appeal, clip them to a coil pack Would I buy the crimper again....? Well, it has done a good job for me on this, but I doubt it would last me more than say 10 sets of leads, but for only £12 delivered I am not going to complain! If I could foresee me doing 10 sets I would have bought the 'proper' one, but for a DIY/budget crimper it has done very well, so yes, very pleased I got one in this case Will this be my first thread in the Tech Archive....? Quote Link to comment Share on other sites More sharing options...
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