MrMasternes Posted July 23, 2017 Report Share Posted July 23, 2017 Hello. Once again I come to this forum to seek your wisdom! I've tried asking around but no one have any idea what the heck is going on. My car did not pass the inspections. The HC value was off the scale it read a value over 2000 when the limit is 400. As I understand HC is hydrocarbons and this means the car is running a little rich which I can already tell by the backfiring sometimes. I've taken the carburetor apart and replaced all the gaskets and given it a thorough clean. I could already feel it running better than before. I think it was leaking a little bit. I also ordered some ignition parts like: A new coil, distributor cap and rotor and new breaker points. They did not have any condensers so I have to source that elsewhere. Unluckily the distributor cap and rotor did not fit. I changed the breaker points on my corolla and set it up to the factory spec. A gap of 0.4 - 0.5 mm when it is at the top. Then I checked it with a dwell angle and got it pretty on point. I also checked the timing with a timing light. But after I changed the breaker points I noticed it was running very rough. It was coughing and spitting fuel out the exhaust. It's like the timing was way off. Then I noticed on my tacho that it was jumping all over the place. I have no idea why it does this. Is the high voltage jumping and shorting somewhere since it's always triggering the tacho? I've uploaded a video to youtube to demonstrate what happends. Quote Link to comment Share on other sites More sharing options...
Banjo Posted July 24, 2017 Report Share Posted July 24, 2017 (edited) Hi Marius, The symptoms you describe are pretty common, and there can be a lot of things that can cause this. Basically, you have to go through each area step by step, & ensure everything in each area is correct & working. The real problem, where it could be a fuel, or an electrical issue, or maybe both, is that a fault in one area, can create a symptom that appears to be caused by the other area. eg: a worn or erratic advance bob weights in the bowels of your distributor, could make the revs jump all over the place, but it could be interpreted as a inconsistent fuel delivery. There are some other areas outside the straight fuel & ignition issues that can cause erratic behaviour. There are mechanical components, that can cause any number of different symptoms, where the engine runs roughly. A good mechanic, faced with an problem engine performance, will systematically go through each area. eg: I've seen K motors with a stuffed timing chain tensioner, that ran reasonably at revs with load, but would not idle for the "love of money". Basic Tests you can do: Mechanical: 1. Remove all spark plugs & do a compression test, & see how close to each cylinders readings are to each other. This will determine whether rings & or valve seating are OK. 2. Remove rocker cover & ensure tappet settings are OK. 3. Check oil pressure with proper guage. Fuel: 1. Check fuel pump delivery & fuel tank breathing etc. 2. Completely dissemble carby & clean & reassemble, and adjust float level setting (very important). 3. Check the very fine filter in the inlet fuel line to the carby. (remove needle & unscrew brass seat fitting). 4. Check the accelerator pump action. 5. Check the action of the electric solenoid on the carby, which cuts out fuel flow immediately ignition is shut down. 6. Change Fit new fuel filter. (even a filter that was replaced recently, might have suffered a bad batch of fuel) 7. If you haven't paid attention to your fuel tank for a long time, then remove, drain & clean it. (Altezzaclub will endorse this suggestion) 8. Check all the little rubber hoses & valves etc. attached to the carby for pollution control. 9. Check & clean the PCV (positive crankcase ventilation) valve on the top of the rocker cover. 10. Fit new air filter. Electrical / Ignition: 1. Ensure alternator is working OK, and terminal voltage at battery is OK whilst running. 2. Check spark plugs or renew. 3. Check dizzy cap for HV break down. 4. Check H.T. leads for breakdown. (best done at night in the dark)5. Check points & settings or renew. 6. Check or replace condensor. 7. Dissemble dizzy, & check the advance bob weights & springs. 8. Check the vacuum advance unit as part of the dizzy. 9. Check starting resistor attached to the coil if fitted. 10. Disconnect anything non standard, connected to the ignition system, like tachos etc. So there is a few tips, and others might like to add some other pointers, I have omitted. These suggestions are random in the listing order; however, if you go through things systematically, the result will be you must find the issue, and will solve your issue. I hope that assists in solving your problem, & let us know what you find. Cheers Banjo Edited July 24, 2017 by Banjo Quote Link to comment Share on other sites More sharing options...
Banjo Posted July 24, 2017 Report Share Posted July 24, 2017 Hi Marius, Just quickly checking your previous post on Rollaclub, I was reminded that a few years ago, you were contemplating reconditioning your engine, or maybe fitting another second had motor. Did you take either of those actions, or is your existing engine, still pretty much as it was back several years ago ? Cheers Banjo Quote Link to comment Share on other sites More sharing options...
MrMasternes Posted July 24, 2017 Author Report Share Posted July 24, 2017 It was when I first got the car almost a year ago :) I haven't gotten around messing with it since it has been my daily since my other car needs repairs. Also I've finnished my studies and started working so I have some money again! It's still the same 3K-H engine that came with the car originally. This problem only occoured after I changed the breaker points on my corolla. Quote Link to comment Share on other sites More sharing options...
Banjo Posted July 25, 2017 Report Share Posted July 25, 2017 Hi Marius, OK, so this happened as soon as you changed the points, & you didn't touch or adjust anything else ? Did you remove the dizzy to fit the points, or did you change the points with the dizzy still in the engine ? Are the new points exactly the same as the one you took out ? Did you clean the protective coating off the points faces themselves, which some manufactures apply ? The points gap setting can change the timing slightly, if it is out, but you advised you set it correctly, & the timing light indicated advance OK. Are you by any chance living at altitude ? Corolla 3K engines are very sensitive to timing changes at altitude. I'm going to take a guess here. When you removed the dizzy cap to fit the new points, did you lay the dizzy cap with leads still attached to one side, of back over the rocker cover? If so, it is possible, that you have a cracked or broken an HT cable to one plug. Have a look under the bonnet at night in the dark, with the engine running, & see if you can see any "corona light shows". Another possibility is the small carbon spring mounted connector for the HT in the inside centre top of the dizzy cap. It didn't happen to fall out, did it ?. The little springs have also been known to break. Let us know what you find. Cheers Banjo Quote Link to comment Share on other sites More sharing options...
MrMasternes Posted July 25, 2017 Author Report Share Posted July 25, 2017 The coil seems to fire when it's not supposed to. I think that's why it jumps on the tacho. Yeah it did happen as soon as I changed the breaker points. I also changed it with the dizzy on the engine. I just lifted up the cap. The points look exactly like the old ones. I did not see any protective coating... do you need to brush the surface with sandpaper or something? I've checked with a multimeter that it is conductive when the point is closed and it breaks the circuit when it's open. The timing is fine as far as I can tell. I've checked with a timing light. My only concern is that the timing might be advancing too much when the rpm goes up. I live pretty much at ocean altitude haha so that is no concern :) At first I removed all the leads and then removed the cap but after a while I realized it's just easier to remove the cap while the lead is still on and then move it to the side. While thinking about it I did get an electric shock going near one of the wires when the engine was running. I might have to check the HT wires conductivity. I'll order some right away. These are probably the original 40 year old wires that came with the car. I cannot check for a light show at night since we still have midnight sun for another couple of weeks. I'll have to wait over a month until it gets dark outside haha. Thanks banjo I'll keep on looking. Quote Link to comment Share on other sites More sharing options...
Banjo Posted July 26, 2017 Report Share Posted July 26, 2017 Hi Marius, I think you are onto it. I'm still betting it is the HT leads. Let us know how you go, once you've replaced them. Better still, if you can get the correct new dizzy cap, that would be better. Tracking on the inside of the cap, is not uncommon, & really the only way to fix that permanently, is to fit a new cap. Cheers Banjo Quote Link to comment Share on other sites More sharing options...
MrMasternes Posted August 9, 2017 Author Report Share Posted August 9, 2017 New problem. Ignition only occours when the starter is engaged... Any ideas @Banjo ? Quote Link to comment Share on other sites More sharing options...
oh what a nissan feeling! Posted August 9, 2017 Report Share Posted August 9, 2017 It sounds like you have lost power on the resistor circuit to the coil. Check fuses under dash, check resistor (white ceramic thing beside coil). Quote Link to comment Share on other sites More sharing options...
Banjo Posted August 9, 2017 Report Share Posted August 9, 2017 (edited) Hi Marius, Quote It sounds like you have lost power on the resistor circuit to the coil. Check fuses under dash, check resistor (white ceramic thing beside coil). Spot on ! When the ignition barrel switch is in the start position, the resistor is effectively shorted out, & power is temporarily connected to the +ve terminal of the coil, whilst the ignition key is in the "START" position.. A quick test would be to short the resistor out, which is adjacent to the coil, & see if the engine runs. If it does, then the resistor has gone open circuit & should be replaced. If it still doesn't start, then go looking for why power isn't getting to the end of the resistor that is NOT connected to the coil. Could be a fuse or wiring or ignition barrel issue. Let us know what you find. P.S. There is no danger in shorting the resistor out for short periods. Coil may get a little bit warmer, if run for long periods, but doubt that would be an issue in Norway, despite it currently being Summer there. Cheers Banjo Edited August 9, 2017 by Banjo Quote Link to comment Share on other sites More sharing options...
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