1969Mk3Spitfire Posted June 19, 2022 Report Share Posted June 19, 2022 I (think) that I've solved my sooty plug issue, choke lever, and I've blown-through and cleaned the fuel system from pump to pipes to float chambers and jets. I still have the misfire symptoms. Could all of my recent grief been a red herring 😭 Cars runs really well for about 5 miles. Water temp gauge reading normal but by now engine is hot. It seems to miss under all driving conditions including low load steady state and mild acceleration. The only two ignition components that I haven't changed are condenser (I bought an Intermotor but it did not fit the Delco distributor due to a poorly made bracket) and coil. Could either of these gives rises to hot engine, not cold, misfire? Anything else to investigate? Any recommendations for a decent condenser and a 12v, non-ballast coil? Many thanks. Link to comment Share on other sites More sharing options...
Badwolf Posted June 19, 2022 Report Share Posted June 19, 2022 PeteL will give you chapter and verse on dodgy condensers, just wait!!! As for coils, not my thing I'm afraid. I have a box of two or three spares from scrappies for years gone by. I just swop if needs be, so no help there, sorry. Glad that you appear to have sorted sooty out. Link to comment Share on other sites More sharing options...
Andy Moss Posted June 19, 2022 Report Share Posted June 19, 2022 Wouldn’t bother with fuel on this one. So you have changed the plugs, HT leads, dizzy cap? Then points, condenser, coil. Are the points fouled? Dwell set correctly? Advance at 6deg BTDC. when you say misfire - what are you hearing exactly? Link to comment Share on other sites More sharing options...
1969Mk3Spitfire Posted June 19, 2022 Author Report Share Posted June 19, 2022 12 minutes ago, Badwolf said: PeteL will give you chapter and verse on dodgy condensers, just wait!!! As for coils, not my thing I'm afraid. I have a box of two or three spares from scrappies for years gone by. I just swop if needs be, so no help there, sorry. Glad that you appear to have sorted sooty out. So, who makes decent condensers? Link to comment Share on other sites More sharing options...
1969Mk3Spitfire Posted June 19, 2022 Author Report Share Posted June 19, 2022 9 minutes ago, Andy Moss said: Wouldn’t bother with fuel on this one. So you have changed the plugs, HT leads, dizzy cap? Then points, condenser, coil. Are the points fouled? Dwell set correctly? Advance at 6deg BTDC. when you say misfire - what are you hearing exactly? Yes, Andy, plugs, points, HT leads, rotor arm and dizzy cap. All from club shop. Not checked points condition in a while so I’ll check and post finding, probably tomorrow. I have a Draper Dwell meter and the engine is within 1 degree of nominal spec. Never checked timing but the car runs extremely well until it’s covered 5 miles 😩 Whether on country lanes or around town, it drives really well for around 5-10 miles. First symptom tends to a single miss with almost instant recovery. It seems most pronounced at light load, steady state, say 40 mph on a flat road. When accelerating, either from standing start or transient, it will miss frequently, almost kangaroo hopping. Accelerating harder, the car pulls but will misfire. The plugs are less than 500 miles old but they have been removed and refitted to different cylinders a million times so it is probably sensible to fit new again, I use NGK BE5S. Appreciate your comments. Link to comment Share on other sites More sharing options...
Pete Lewis Posted June 19, 2022 Report Share Posted June 19, 2022 get a condenser from the distributor doctor if you have a delco talk to him Delco condenser: 829111,829107,1861709,1866049,18655972, 1869704,1882239, Lucas Condenser 484249, 400308, 407044, 54411935 / DCB105, 54413006, 23D4 22D 23D DM2 25D DM6 DM4 lucas distributor, Lucas condenser number 423871, GDC101. Condensor 405833 for Ford 8 and Ford 10, Lucas condensers from Distributor Doctor Pete Link to comment Share on other sites More sharing options...
Pete Lewis Posted June 19, 2022 Report Share Posted June 19, 2022 any hint of a back fire is condenser letting go is the electronic or on points as im getting a bit lost Pete Link to comment Share on other sites More sharing options...
1969Mk3Spitfire Posted June 20, 2022 Author Report Share Posted June 20, 2022 8 hours ago, Pete Lewis said: any hint of a back fire is condenser letting go is the electronic or on points as im getting a bit lost Pete There’s no backfire, Pete. Car is standard and original so it’s points and 12v, non-ballast coil. Link to comment Share on other sites More sharing options...
1969Mk3Spitfire Posted June 20, 2022 Author Report Share Posted June 20, 2022 @Badwolf I’ve had this problem before with this forum. I have the start of your last comment as an email message but can’t see the post within this thread 🤷♂️ My ignition is original, not converted to electronic. Link to comment Share on other sites More sharing options...
NonMember Posted June 20, 2022 Report Share Posted June 20, 2022 Could be a weak coil, points, condenser, or plugs, especially if the plugs are NGK and have been in there since before you sorted the fouling issue. Link to comment Share on other sites More sharing options...
1969Mk3Spitfire Posted June 20, 2022 Author Report Share Posted June 20, 2022 14 hours ago, Andy Moss said: Are the points fouled? Checked the points this morning and they are fine. Link to comment Share on other sites More sharing options...
1969Mk3Spitfire Posted June 20, 2022 Author Report Share Posted June 20, 2022 8 minutes ago, NonMember said: Could be a weak coil, points, condenser, or plugs, especially if the plugs are NGK and have been in there since before you sorted the fouling issue. Thanks, I’m planning to replace the plugs and the condenser. Any recommendations for make/type of coil? Many seem to offer a standard coil and a “high performance” version. What does HP mean in this context and might it be of help? Link to comment Share on other sites More sharing options...
Badwolf Posted June 20, 2022 Report Share Posted June 20, 2022 3 hours ago, 1969Mk3Spitfire said: @Badwolf I’ve had this problem before with this forum. I have the start of your last comment as an email message but can’t see the post within this thread 🤷♂️ My fault. Sent a post through and realised that it was for the wrong thread so deleted it. Unfortunately you got an email notification to say that you had a new post even through I has made a mess. Apologies. Link to comment Share on other sites More sharing options...
Ian Foster Posted June 20, 2022 Report Share Posted June 20, 2022 A faulty condenser will certainly cause a misfire under load and I had this issue on my GT6 (Delco) many years ago. Luckily I was carrying a spare and a simple swop sorted it out. The quality of aftermarket condensers can be iffy so try and source from a reputable dealer of substitute one from another car that is known to be OK. Ian Link to comment Share on other sites More sharing options...
Pete Lewis Posted June 20, 2022 Report Share Posted June 20, 2022 i had a local spitty that would run like a complete bag of sh1te you could twiddle all morning it would run fine after for 5 miles and turn into a nightmare it eventually demised to no further that its drive fitted a dizzy doc condenser and shes been fine ever since but for all my magic fingers didnt point to condenser for a good while too long HD on a coil is often just the label .......... any 3 ohm coil is ok like DLB101 or a supposed sports version DLB105 both are 3 ohm non ballast coils Pete Link to comment Share on other sites More sharing options...
Badwolf Posted June 20, 2022 Report Share Posted June 20, 2022 Is there any way to spot a dodgy condenser by putting a meter on it, and if so how do you do it. Obviously the electricity knows it's a rubbish unit, how do we? Link to comment Share on other sites More sharing options...
johny Posted June 20, 2022 Report Share Posted June 20, 2022 After first discharging a capacitor/condenser I find when I put a meter on it the resistance shows as low to start and then climbs to a high value as it charges up. Then with the meter on volts you might even be able to get a reading as it retains the charge - you could even charge it up on the car battery and check its stored some volts. Of course this isnt a guarantee the unit will be good in service but its sure that if you see a continual low or high resistance it has a problem.... Link to comment Share on other sites More sharing options...
PeteH Posted June 20, 2022 Report Share Posted June 20, 2022 I think, that if you use a Multimeter, on the Ohm`s range, It should rise reasonably slowly to a peak reading. if nothing happens or the rise is instant, assume the Condenser to be defective?. It`s a LOT of years since I tested one, but I think that is correct?. They are (or used to be) cheap as chips, and I tended to replace any time I replaced the points. Pete Link to comment Share on other sites More sharing options...
NonMember Posted June 20, 2022 Report Share Posted June 20, 2022 4 minutes ago, johny said: After first discharging a capacitor/condenser I find when I put a meter on it the resistance shows as low to start 4 minutes ago, PeteH said: I think, that if you use a Multimeter, on the Ohm`s range, It should rise reasonably slowly to a peak reading While this is a good way to test a fairly hefty (e.g. electrolytic) capacitor, the definition of "slowly" for an ignition condenser is probably too fast to notice. The multimeter may only be putting a tiny fraction of the ignition current into it, but it's only aiming for a volt or two, while in operation the condenser needs to swing from 0V to 300V in a fraction of a millisecond, or you don't get a spark. Link to comment Share on other sites More sharing options...
1969Mk3Spitfire Posted June 20, 2022 Author Report Share Posted June 20, 2022 7 hours ago, Pete Lewis said: fitted a dizzy doc condenser and shes been fine ever since but for all my magic fingers didnt point to condenser for a good while too long Pete Dear magic fingers, I’ve ordered one and if it doesn’t solve the problem I’ll be sending the boys round for a chat 😁 (thanks for your help, notwithstanding) Link to comment Share on other sites More sharing options...
1969Mk3Spitfire Posted June 20, 2022 Author Report Share Posted June 20, 2022 The condenser spec is 0.18 to 0.24 microfarads. I have an LRC meter and have measured mine at 0.21, so within spec. Sadly, I don’t think that a static measurement like this is sufficient to assess dynamic, load and heat affect. I know there are advocates (sensible people) of assessing the effect of a single change but I’m planning to simultaneously change condenser, plugs and coil. No real reason to doubt any of these but I’m otherwise running out of ideas. Beating the car with the branch of a tree as per John Cleese is next on my list. Link to comment Share on other sites More sharing options...
daverclasper Posted June 20, 2022 Report Share Posted June 20, 2022 25 minutes ago, 1969Mk3Spitfire said: I know there are advocates (sensible people) of assessing the effect of a single change but I’m planning to simultaneously change condenser, plugs and coil. No real reason to doubt any of these but I’m otherwise running out of ideas. Maybe worth taking the spares out and when car is hot changing one at a time at the roadside, if you can be bothered?. You should then have spares for the future that you know should be working Link to comment Share on other sites More sharing options...
1969Mk3Spitfire Posted June 23, 2022 Author Report Share Posted June 23, 2022 Update. As per advice within this thread I have today replaced condenser, coil and new plugs (again). Just been for a 15 mile drive in a mixture of 30, 40, 50 and 60 limits on a hot ambient day. For the first time in months the car did not misfire! Fingers crossed that both my sooty plug and misfire issues are now resolved. Huge thanks to all for help and advice along the way. Odometer turned to 55,000 during the drive. Link to comment Share on other sites More sharing options...
Badwolf Posted June 23, 2022 Report Share Posted June 23, 2022 Great news, now the question, which one was the culprit? Link to comment Share on other sites More sharing options...
Chris A Posted June 23, 2022 Report Share Posted June 23, 2022 4 minutes ago, Badwolf said: Great news, now the question, which one was the culprit? In turn refit each of the old stuff one at a time until . . . Link to comment Share on other sites More sharing options...
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