Josh Posted June 28, 2019 Report Share Posted June 28, 2019 I’ve just this week joined the TR-Register. I am having problems starting my 1974 TR6, which I have had for a couple of years, which has always struggled to start from cold (original starter motor, not hi-torque). It had recently started to misfire occassionally which progressed to misfiring badly just over a month ago. I briefly checked plugs, and electrics, which all appeared to be fine. So I then moved my attentions to checking fuel supply, specifically injectors, to find one of the injectors had disassembled itself, but all parts were still intact inside. I removed all injectors, and had them refurbished, refitted, and bled them. Since refitting, I have not managed to get the car into life since replacing the serviced injectors, which I believe are now in fine fettle. My initial throught for the car not kicking into life, was the fact that the injectors are now set NOP @ 60psi, whereas they were previously in the range 52-60PSI, which I wondered may be causing issues further down the fuel line. However, I have so far decided not to touch either the Pump, PRV, or Metering Unit after the injector refurbishment. The car has not run for over a month. Before going down the route of checking/adjusting what to date has been a working Pump, PRV & Metering Unit setup, I decided to recheck electrics, to find there does not appear to be any sign of a spark at the plugs. There does appear to be fuel getting to each of the pots, because when I turn the engine over, I have pulled each plug out and found each of them are fuel covered, having not fired! I have checked and replaced coil, points, & condenser. HT leads appear to be electrically intact end to end, if I believe the results of my multimeter testing, so I have not yet changed distributor cap, or HT leads. I have done continuity & voltage checks, which show there is now power to coil, LT & HT, and HT @ the distributor cap. One final thought for concern is that the main battery lead to the starter motor does get extremely warm after multiple attempts to turn the car over, - just wonder if a problem with starter motor could be contributing to reducing available power for fuel pump, and power at plugs? I’m now starting to doubt my own fault-finding as the car still does not appear to be firing! I’m based in Gerrards Cross, so any help, guidance, suggestions would be gratefully received. Josh Quote Link to post Share on other sites
Tim D. Posted June 28, 2019 Report Share Posted June 28, 2019 I suspect that you've ended up flooding the car (hence wet plugs) and this will prevent further attempts to start. Before you do anything give the plugs a clean and dry them out or buy some new ones. It is also possible that the voltage is dropping when you are cranking to such a level that you do not get a good spark and hence plugs get wet and you are stuck. Two options could be temporarily piggy backing another battery onto the car using jump leads. This should give enough extra kick to make the voltage drop negligible. Second option (not liked by all) would be to spray some ether (available in cans for starting engines) into the inlet and then try starting. I have found this gets most things going when the spark is weak. Not a permanent solution but might get things going. If it doesn't start on ether then spark would definitely be suspect. Tim Quote Link to post Share on other sites
RogerH Posted June 28, 2019 Report Share Posted June 28, 2019 Hi Josh, wet plugs can kill them permanently. Fit new ones. TRy testing the ignition system by removing all plugs and then spin the engine over (Ignition ON) and see if you can get a spark. If no sparks, then remove the centre Dizzy cap lead and see if you can get a spark form this. Roger Quote Link to post Share on other sites
Waldi Posted June 28, 2019 Report Share Posted June 28, 2019 I agree with Tim above. I would measure battery voltage during starting, it should well above 10-11V. Then measure voltage at coil “feed”, it could be a bit lower but not much. You can also put one HT lead on an additional plug, hold that against the engine, and see if and how strong the spark is. Beware for a shock, especially if you have a high voltage /high energy coil. Since you have wet plugs (fuel), this is not the most like cause if it does not fire at all. Waldi Quote Link to post Share on other sites
Josh Posted June 28, 2019 Author Report Share Posted June 28, 2019 Thanks to you all for your helpful suggestions. I have comnbined Tim's and Roger's suggestions and connected another battery from another running car. I then turned the car over for 1.5-2 minutes with no response from the engine. I then removed the distributor cap and turned over again to find no spark being generated at the (new) set of contact breaker. Additionally the starter motor started to smoke while the car was turning over. I am therefore thinking I may at least have a starter motor problem. I now need to do some further investigations to try to isolate the reason why there is no spark at the cb. Any further suggestions welcomed. Quote Link to post Share on other sites
RogerH Posted June 28, 2019 Report Share Posted June 28, 2019 Hi Josh, it would be worth rechecking the installation of the new CB's and fit a known old working condensor. If either were short circuit then the sparks disappear to earth. Roger Quote Link to post Share on other sites
Waldi Posted June 28, 2019 Report Share Posted June 28, 2019 Regarding the starter motor: Find out where the starter motor is smoking from. It could be just a loose connection from the thick red cable to the starter motor terminal. And only use the starter motor in short intervals. if you have removed the distributor cap you cannot see sparks, so not sure what you mean. The contact points should also not spark (but they sometimes do. Are the wires to the points connected correct? If you disconnect the white wire and open the points, the wire inside the dizzy to the points should not make contact with earth, so infinite resistance. Waldi Quote Link to post Share on other sites
astontr6 Posted June 28, 2019 Report Share Posted June 28, 2019 11 hours ago, Josh said: I’ve just this week joined the TR-Register. I am having problems starting my 1974 TR6, which I have had for a couple of years, which has always struggled to start from cold (original starter motor, not hi-torque). It had recently started to misfire occassionally which progressed to misfiring badly just over a month ago. I briefly checked plugs, and electrics, which all appeared to be fine. So I then moved my attentions to checking fuel supply, specifically injectors, to find one of the injectors had disassembled itself, but all parts were still intact inside. I removed all injectors, and had them refurbished, refitted, and bled them. Since refitting, I have not managed to get the car into life since replacing the serviced injectors, which I believe are now in fine fettle. My initial throught for the car not kicking into life, was the fact that the injectors are now set NOP @ 60psi, whereas they were previously in the range 52-60PSI, which I wondered may be causing issues further down the fuel line. However, I have so far decided not to touch either the Pump, PRV, or Metering Unit after the injector refurbishment. The car has not run for over a month. Before going down the route of checking/adjusting what to date has been a working Pump, PRV & Metering Unit setup, I decided to recheck electrics, to find there does not appear to be any sign of a spark at the plugs. There does appear to be fuel getting to each of the pots, because when I turn the engine over, I have pulled each plug out and found each of them are fuel covered, having not fired! I have checked and replaced coil, points, & condenser. HT leads appear to be electrically intact end to end, if I believe the results of my multimeter testing, so I have not yet changed distributor cap, or HT leads. I have done continuity & voltage checks, which show there is now power to coil, LT & HT, and HT @ the distributor cap. One final thought for concern is that the main battery lead to the starter motor does get extremely warm after multiple attempts to turn the car over, - just wonder if a problem with starter motor could be contributing to reducing available power for fuel pump, and power at plugs? I’m now starting to doubt my own fault-finding as the car still does not appear to be firing! I’m based in Gerrards Cross, so any help, guidance, suggestions would be gratefully received. Josh Josh, I live in Burnham, Bucks. If your Gerrards Cross is the same as the one near me send me a mail and your tel.no and I will come over to see if I can sort it out. Bruce. Quote Link to post Share on other sites
Sapphire72 Posted June 28, 2019 Report Share Posted June 28, 2019 (edited) I've had this no start issue, at which time the Low-Tension lead (between the contact-point post & the side of the distributor) had frayed apart wires within the sheathing. You can't see this problem with the sheathing covering the wire strands. You did say that you checked the LT & HT, but here is another persons experience. And, yes, once spark plugs get soaked, it is important to replace them with new. Another thing which can deter a start-up, is the sequence in which the distributor post is loaded. Be sure you stack the dist. post in the manner shown in this Owners Workshop Manual. Edited June 29, 2019 by Sapphire72 Quote Link to post Share on other sites
rocket ron Posted June 30, 2019 Report Share Posted June 30, 2019 Hi I had a similar problem with my Volvo 240 (265.000 Miles) But i do also have a TR6.The starter motor was playing up had to tap the solenoid to get it to turn over sometimes.Changed the starter motor and its fine was the faulty starter taking all the amps?Regards Ron. Quote Link to post Share on other sites
Josh Posted July 5, 2019 Author Report Share Posted July 5, 2019 Just a brief update to thank Bruce for his helping in person to identify and fix this issue, which turned out to be an electrical supply/wiring issue from the ignition switch. So I was seeing zero volts being delivered to the LT side of the coil. Regards Josh Quote Link to post Share on other sites
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