Edwin Posted August 5, 2009 Report Share Posted August 5, 2009 Hello, I am having a very frustrating problem with the ignition timing on my TR6 (1970). I already read a lot of other posts but could not find the answer in any of them. When I set the static timing at 12 BTDC according to the manual the dynamic timing at idle (900-1000 rpm) is almost 24 BTDC (with or without advance line connected). Because the vacuum retard was removed the static and dynamic timing should be the same!? It is a standard engine and i checked the following: - contact point gap is set to standard - new spark plugs (NGK BP5ES) with the standard gap (0,025") - vacuum retard was broken so I removed it (new carbs do not even have a option to connect the line) - valve clearance adjusted and checked - it has brand new SU HS6 carbs especially made for a TR6 with the correct needles (done by www.sucarb.co.uk) - the airflow of the carbs is perfectly balanced - vacuum advance is connected (to top of front carb) and working (no leaks) - at TDC the rotor in the distributor is pointing at the spark plug wire for cylinder no 1, the way it should be I think And because of this timing issue (at least I think that is the cause) the car will not accelerate at all. only the slightest bit of pedal movement will make it go faster (slowly). But when trying to push the pedal in a normal way will make it stutter and not pick up any speed, it's like it is stalling itself. I am really confused as to why the dynamic timing is way off. Am i overlooking something or is the distributor broken and how can i tell if it is..... Please help me with the very frustrating problem. Kind regards, Edwin Treffers Quote Link to post Share on other sites
RobinTR6 Posted August 5, 2009 Report Share Posted August 5, 2009 Hello, I am having a very frustrating problem with the ignition timing on my TR6 (1970). I already read a lot of other posts but could not find the answer in any of them. When I set the static timing at 12 BTDC according to the manual the dynamic timing at idle (900-1000 rpm) is almost 24 BTDC (with or without advance line connected). Because the vacuum retard was removed the static and dynamic timing should be the same!? It is a standard engine and i checked the following: - contact point gap is set to standard - new spark plugs (NGK BP5ES) with the standard gap (0,025") - vacuum retard was broken so I removed it (new carbs do not even have a option to connect the line) - valve clearance adjusted and checked - it has brand new SU HS6 carbs especially made for a TR6 with the correct needles (done by www.sucarb.co.uk) - the airflow of the carbs is perfectly balanced - vacuum advance is connected (to top of front carb) and working (no leaks) - at TDC the rotor in the distributor is pointing at the spark plug wire for cylinder no 1, the way it should be I think And because of this timing issue (at least I think that is the cause) the car will not accelerate at all. only the slightest bit of pedal movement will make it go faster (slowly). But when trying to push the pedal in a normal way will make it stutter and not pick up any speed, it's like it is stalling itself. I am really confused as to why the dynamic timing is way off. Am i overlooking something or is the distributor broken and how can i tell if it is..... Please help me with the very frustrating problem. Kind regards, Edwin Treffers Why do you think its the timing, most would recommend turning the dizzy from retarded to advanced until she runs a bit rough then back of a couple of degrees. Its worked for me for years. Is it getting enough petrol, if it starts the timing cant be all that bad. I would suggest tht you look at the petrol side of things as well, float chambers etc to ensure its getting enough petrol. Quote Link to post Share on other sites
88V8 Posted August 5, 2009 Report Share Posted August 5, 2009 I'm about to go out and don't have time to look it up in the Brown Bible, but the dynamic advance starts below 900rpm, to check the timing I think you should be idling it slower. Did it run OK before you did whatever you recently did? What was it you did since then? Ivor Quote Link to post Share on other sites
PILKIE Posted August 5, 2009 Report Share Posted August 5, 2009 Have you set the mixture on the carbs? Twin SU's have a natural tendancy to want to run rich on tickover to ensure the car runs ok at revs! If you set them so the readings are spot on,when you open the throttle,its like fuel starvation happening. I set my carbs mixture on my rover v8 with it running at about 2000rpm,or when I set it on tickover,I set them up,then I give them 1/4-1/2 turn to the rich. Currently get about 25mpg on a run and 17mpg just local. Quote Link to post Share on other sites
TONYL Posted August 5, 2009 Report Share Posted August 5, 2009 Hello, I am having a very frustrating problem with the ignition timing on my TR6 (1970). I already read a lot of other posts but could not find the answer in any of them. When I set the static timing at 12 BTDC according to the manual the dynamic timing at idle (900-1000 rpm) is almost 24 BTDC (with or without advance line connected). Because the vacuum retard was removed the static and dynamic timing should be the same!? It is a standard engine and i checked the following: - contact point gap is set to standard - new spark plugs (NGK BP5ES) with the standard gap (0,025") - vacuum retard was broken so I removed it (new carbs do not even have a option to connect the line) - valve clearance adjusted and checked - it has brand new SU HS6 carbs especially made for a TR6 with the correct needles (done by www.sucarb.co.uk) - the airflow of the carbs is perfectly balanced - vacuum advance is connected (to top of front carb) and working (no leaks) - at TDC the rotor in the distributor is pointing at the spark plug wire for cylinder no 1, the way it should be I think And because of this timing issue (at least I think that is the cause) the car will not accelerate at all. only the slightest bit of pedal movement will make it go faster (slowly). But when trying to push the pedal in a normal way will make it stutter and not pick up any speed, it's like it is stalling itself. I am really confused as to why the dynamic timing is way off. Am i overlooking something or is the distributor broken and how can i tell if it is..... Please help me with the very frustrating problem. Kind regards, Edwin Treffers Hi Is this a 150 PI now running carbs? The dizzy on the PI has no vacuum advance and should be set with the tick over around 7-8000 revs so as not to bring in the mechanicle advance. What needles are fitted and are the pistons moving freely? Tony Quote Link to post Share on other sites
Edwin Posted August 5, 2009 Author Report Share Posted August 5, 2009 Hello everyone, I am very pleased to say that the problem has been solved..... Upon the suggestion to check the fuel supply I checked every line and was shocked to find that one of the carbs was malfunctioning. I bought these SU HS6 carbs brand new and (of course) assumed they would be perfect: they were NOT !! On the front carb the fuel line going from the float chamber to the metering needle was almost disconnected at the float chamber side. So fuel was leaking heavily from the underside which could have set the TR6 on fire Once I took it apart and reassembled everything the car goes like never before, really unbelievable and what a joy to feel the acceleration... Thank's everyone for you advise and comments. It always amazes me how many of you reply on such short notice: THANKS !! And now I'm going back on the road because the sun is shining and it's 30 degrees outside. Regards, Edwin Quote Link to post Share on other sites
grahama Posted August 5, 2009 Report Share Posted August 5, 2009 Edwin, jolly well done! Now....if you can arrange to ship some of that 30C sunshine over here it just might inspire me to finish my to do list before winter arrives (did someone say it already arrived a few weeks ago!). Graham Quote Link to post Share on other sites
PILKIE Posted August 5, 2009 Report Share Posted August 5, 2009 Glad you resolved it before cathing it on fire! I am off for a blast while the suns out! Quote Link to post Share on other sites
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