Peter Cobbold Posted September 17, 2014 Report Share Posted September 17, 2014 Maybe its a loose wire in the coil- try moving the coil to the bulkhead away from engine vibration? Quote Link to post Share on other sites
Leif Posted September 17, 2014 Author Report Share Posted September 17, 2014 Maybe... Today I drove around for more then one hour listening to static from the ignition system on the radio, and I had it turned up really loud too. (I wonder what people thought when I drove by.) But this time there wasn't any hick-ups so it was wasted time. It was not fun to listen to either, it actually got boring really really quick. Quote Link to post Share on other sites
Steves_TR6 Posted September 17, 2014 Report Share Posted September 17, 2014 I still think it's low tension electrics. I'd rig up an entire new lt circuit. Fused switched lead from battery for power, new lt wires to and from distrib to coil, and new points and condenser. Also new earthing. If this cures the problem then backtrack from there. If it doesn't cure the problem at least you know it's not LT! Steve Quote Link to post Share on other sites
Ragtag Posted September 17, 2014 Report Share Posted September 17, 2014 I was going to post before but never got round to it and in the time elapsed, you have made a couple of he checks I would have suggested...sort of. You have confirmed the fuel pump works during a cutting out episode but I would like to know if, during a cut out, you go into neutral can you rev the engine, rather than waitng for the revs to drop. Reason for the question is another old addage, misfire under load suggests Hi Tension. Having said that, I'm with Steve D in suspecting the LT circuit. However, I would go further and suggest you 'bite the bullet' and make a few purchases of items that will undoubtably improve your TR anyway (assuming you aren't a concours wallah) and might solve the problem en route. Distributor cap and rotor from Martin Jay Aldon/Pertronix/Accuspark ignition (removes points & condenser) Lucas DLB105 Coil (also make sure you don't have a ballast resistor) New NGK spark plugs Magnacor 85 kva Leads. Quote Link to post Share on other sites
Peter Cobbold Posted September 18, 2014 Report Share Posted September 18, 2014 I do tend to think its the spark thats at fault. But it is possible to have good fuel pressure and good spark but still have a dead engine - if the MU rotor stops turning. So heres the test for the MU stalled: Next time it fails keep the throttle wide open. When it restarts if you get an exhaust backfire, its the spark that was lost. If you dont get a bang in the exhaust, it has not filled with unburned mixture, and points to the MU rotor stopping. The rotor is turned by a red plastic, slotted adaptor- it may be possible that is damaged, although I've ever heard of it stop then start working again. Quote Link to post Share on other sites
JohnC Posted September 19, 2014 Report Share Posted September 19, 2014 Maybe... Today I drove around for more then one hour listening to static from the ignition system on the radio, and I had it turned up really loud too. (I wonder what people thought when I drove by.) But this time there wasn't any hick-ups so it was wasted time. It was not fun to listen to either, it actually got boring really really quick. I'm so glad that others do things non-believers would think utterly incomprehensible in the name of understanding! Leif, I feel your pain But really good diagnostic idea. Cheers, John Quote Link to post Share on other sites
Leif Posted September 23, 2014 Author Report Share Posted September 23, 2014 A couple of days ago I spent another hour listening to ignition static on the radio with the car running perfectly the entire trip. But today I went for another ride and this time the engine died several times, and most of the times it started again as usual if I just let the rpm drop to near zero. But then there was some times when it just stayed dead, and I had to stop at the side of the road and it just wouldn't start again. But also the static on the radio was gone, only the high pitched sound from the generator was still there. So there is no spark when it dies. The scary part now was that it died so often that I was starting to be afraid that I might not be able to get home. (The generator is charging, but not much...so the battery isn't that powerful, but that is next on the list). Anyhow, when it died and stayed dead, I went out searching for faults under the hood. With ignition on I measured the voltage at the coil. It did have 12V on both sides so I figured the breaker points had to be open. So next step was to check under the distributor cap and measure on the points, hm they seem to be closed. I opened them manually and a little spark could be seen between the points. Now is that normal? Shouldn't the capacitor take care of that? So the points where closed, hm, I measured again on the coil and now I didn't have 12V on both sides so something had changed while I messed around there. Now I had current flowing through the coil and breaker points. I put the distributor cap on and the engine could be started again. This happened a couple of times. The previous owner had installed a new coil, new wiring and a new distributor cap and everything seemed to be very well done, that's why I haven't exchanged anything yet as some of you have suggested. My bad, because when I started to pull a little harder in the wire between the coil and the distributor it seems as if the contacts aren't pressed well enough. The wire can move back and forth in the contacts, in both ends. This COULD be it. (A little embarrassing if it is though.) Quote Link to post Share on other sites
Peter Cobbold Posted September 23, 2014 Report Share Posted September 23, 2014 The points could be have been closed simply because their cam follower was not on a lobe of the cam! Try cleaning the points with fine sandpaper then set them -with the follower on the apex of the cam - to about 15 thou. Smear a liilte grease on the tip of the follower/cam. It may be that the previous owner fitted new points without sanding them to remove the supplier's protective varnish. The wire that connects to the points terminal fits like this:http://www.paulhunt73.webspace.virginmedia.com/mgb-stuff/images/p25conn.jpg its important that the insulating washer does insulate the wires from the post. Looks like the problem's solved, and we all learned something !! Peter Quote Link to post Share on other sites
Leif Posted October 5, 2014 Author Report Share Posted October 5, 2014 A small update. It seems the problem is solved, the engine has not failed since I exchanged the wire between the ignition coil and the distributor. And with the help of this forum I did learn a few new tricks a TR6 can play, so thanks everyone for the help. Quote Link to post Share on other sites
mike3739 Posted October 5, 2014 Report Share Posted October 5, 2014 A small update. It seems the problem is solved, the engine has not failed since I exchanged the wire between the ignition coil and the distributor. And with the help of this forum I did learn a few new tricks a TR6 can play, so thanks everyone for the help. Good to hear Leif Cheers Mike Quote Link to post Share on other sites
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