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I am a new TR owner and new to BCF. I just bought a 69 TR6. The car is pretty solid but still needs a lot of work. It has an eletronic ingition and I am having trouble with the timing. I don't have the paper work that came with the unit. What is the proper way to set the timing. The OEM specs call for 4 degrees after TDC at idle. When I set the by those specs, The car will barley run. It was set at about 12 degrees before TDC when I started. I moved it back and it runs ok but diesels when you turn the engine off. Help! Have patience guys. I will probably be asking a lot more questions before I am finished
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Petronix ignition
- Thread starter 69tr
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Simon TR4a
Jedi Knight
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It is possible that either the distributor has not been well maintained, has never been lubricated, and will not advance correctly. Also possible the springs that control the advance curve are stretched or broken or seized, or the weights the wrong size or missing.
All this would indicate a need to service/repair the distributor, but as a temporary measure (only!) you could try ignoring all the theoretical settings and simply adjust it to run as well as possible. I would be more concerned that it runs well at 3000 revs than having a factory correct setting at idle and a car you can't drive because the advance curve is way off.
Good luck, Simon.
All this would indicate a need to service/repair the distributor, but as a temporary measure (only!) you could try ignoring all the theoretical settings and simply adjust it to run as well as possible. I would be more concerned that it runs well at 3000 revs than having a factory correct setting at idle and a car you can't drive because the advance curve is way off.
Good luck, Simon.
swift6
Yoda
Offline
The crank damper/pulley could also be in bad shape. The rubber in the damper can crack and allow the outer section to shift. Which completely throws off the timing marks. You can check it by getting cylinder number one (front of the engine) at Top Dead Center (ready to fire) and see if the pointer is even close to the mark on the damper/pulley. You can also get an idea of how close the distributor is as well.
Simon offers some other good ideas too. Make sure your distributor is working correctly. Timing by ear and feel will get it to running. Then you can begin to figure why all the marks are off.
/ubbthreads/images/graemlins/cheers.gif
Simon offers some other good ideas too. Make sure your distributor is working correctly. Timing by ear and feel will get it to running. Then you can begin to figure why all the marks are off.
/ubbthreads/images/graemlins/cheers.gif
G
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Dump the Pertronix, go back to points, do a minor tune-up, set the timing at 8 degrees BTDC, plug any vacumn hole in the carbs and letter rip. The other purpose of brakes and clutch is to stop dieseling. Kill the engine in gear and let the brake stop the dieseling. Try the simple stuff first, get you a good workshop manual and play with her. Triumphs were made to get your fingernails dirty and enjoy.
Bill
Bill
achtungeveryone
Jedi Hopeful
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they tend to deisel with the stepped up timing but they do run better and mine seems to get better milage. My idle increased to about 1100 and I have yet to fix that...My Pertronix has been flawless but that isn't everybody's experience. A back up could is a good idea (...note to self...)
Ach
Ach
bobh
Jedi Warrior
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Try the 10 degrees Bill suggested. If you are able to take it out on the road listen for pinging under load. If it is pinging and it still runs on after shutting it off. Try a higher grade of gas. If the problem persists try 8 degrees. If you have to go much less than that you may need to dig a little deeperas the others suggested.
You may have a vaccuum leak. Most leaks will make a high pitched whistling sound, but not always. A large leak may not produce any sound, at least not anything you can differentiate from the engine noise. An old valve cover gasket can cause problems. After awhile they are saturated in oil. The gasket material gets hard. The oil tends to be sticky when it is cool. Stucky enough to seal the hardened gasket to the cover and the head. As it warms it becomes less sticky and allows air to be sucked in. A faulty seal on the oil filler cap can have the same affect. Neither of these make a distinctive noise. Extra air going into the valve cover has a similar effect as a vaccuum leak. Your vaccuum advance on the distributer probably will not fully engage. A large air leak provides plenty of air and the path of least resistance. Vaccuum created by the engine will such this in instead of drawing in the diaphram in your advance module. My 2nd TVR had a bad valve cover gasket. Once the engine was warm (and the oil on the gasket) it would barely run. I spent many hours trying to find the problem.
You may have a vaccuum leak. Most leaks will make a high pitched whistling sound, but not always. A large leak may not produce any sound, at least not anything you can differentiate from the engine noise. An old valve cover gasket can cause problems. After awhile they are saturated in oil. The gasket material gets hard. The oil tends to be sticky when it is cool. Stucky enough to seal the hardened gasket to the cover and the head. As it warms it becomes less sticky and allows air to be sucked in. A faulty seal on the oil filler cap can have the same affect. Neither of these make a distinctive noise. Extra air going into the valve cover has a similar effect as a vaccuum leak. Your vaccuum advance on the distributer probably will not fully engage. A large air leak provides plenty of air and the path of least resistance. Vaccuum created by the engine will such this in instead of drawing in the diaphram in your advance module. My 2nd TVR had a bad valve cover gasket. Once the engine was warm (and the oil on the gasket) it would barely run. I spent many hours trying to find the problem.
Alan_Myers
Luke Skywalker
Offline
Hi,
Assuming your '69 TR6 is relatively stock and the engine is in good shape, I think it should have about 9.5:1 compression ratio. ISTR later U.S. spec TR6s increasingly had slightly lower CR, as emission controls were added. Because of this, I would suggest sticking with premium gas. The car will simply run better and more efficiently, probably making up for the extra cost of higher grade fuel in the process.
Do avoid pinging (or "pinking" in Brit-speak). It can and will damage an engine over time and indicates timing is over-advanced for the general state of tune and condition of the engine. The trick is essentially to get as much advance as possible and then back off just a little to avoid pinging or, more properly, "pre-detonation". And yes, as mentioned, it's possible to get timing pretty well set just by advancing until the engine reaches the highest idle speed, then back off slightly and test drive to be sure there is no pinging at higher rpms under load. A lot of folks don't bother with a timing light! After this, the carbs can be balanced and finally the idle reset. All this assumes the dizzy and vacuum advance/retard are working correctly.
Since you are new to the car, you might have to adjust timing a couple times. There's no telling how previous owners treated, serviced and maintained the car. Their driving habits might have been such that there is some carbon build-up in the cylinders, which will increase the tendency to ping. However, with some regular driving, especially on the highway, some of that carbon (if there is any) might clear out and the timing could then be set a little more aggreassively.
All the suggestions are excellent. Especially: pick up a manual. The Bentley reprint of the original factory manual is likely the best, but others from Clymers, Autobooks and Haynes can be very helpful, too. Of course, the Bentley manual is usually the most expensive. Try Amazon and eBay for better deals on these manuals, unless you want a brand-spanking new one to smudge up with greasey fingers!
The Petronix is a good unit, although some have reported problems. Problems seem to be most likely to occur if the coil/ballast/condenser aren't well matched with the ignition unit. But, this is just an observation on my part and I don't have Petronix installed on any cars, so can't give any solid specifics or personal experiences.
Oh, one last thing... check that the rotor, dizzy cap, spark plugs and plug wires are correct and all in good condition, gapped properly, etc., before going too deeply into setting the timing.
Have fun and welcome!
/ubbthreads/images/graemlins/cheers.gif
Assuming your '69 TR6 is relatively stock and the engine is in good shape, I think it should have about 9.5:1 compression ratio. ISTR later U.S. spec TR6s increasingly had slightly lower CR, as emission controls were added. Because of this, I would suggest sticking with premium gas. The car will simply run better and more efficiently, probably making up for the extra cost of higher grade fuel in the process.
Do avoid pinging (or "pinking" in Brit-speak). It can and will damage an engine over time and indicates timing is over-advanced for the general state of tune and condition of the engine. The trick is essentially to get as much advance as possible and then back off just a little to avoid pinging or, more properly, "pre-detonation". And yes, as mentioned, it's possible to get timing pretty well set just by advancing until the engine reaches the highest idle speed, then back off slightly and test drive to be sure there is no pinging at higher rpms under load. A lot of folks don't bother with a timing light! After this, the carbs can be balanced and finally the idle reset. All this assumes the dizzy and vacuum advance/retard are working correctly.
Since you are new to the car, you might have to adjust timing a couple times. There's no telling how previous owners treated, serviced and maintained the car. Their driving habits might have been such that there is some carbon build-up in the cylinders, which will increase the tendency to ping. However, with some regular driving, especially on the highway, some of that carbon (if there is any) might clear out and the timing could then be set a little more aggreassively.
All the suggestions are excellent. Especially: pick up a manual. The Bentley reprint of the original factory manual is likely the best, but others from Clymers, Autobooks and Haynes can be very helpful, too. Of course, the Bentley manual is usually the most expensive. Try Amazon and eBay for better deals on these manuals, unless you want a brand-spanking new one to smudge up with greasey fingers!
The Petronix is a good unit, although some have reported problems. Problems seem to be most likely to occur if the coil/ballast/condenser aren't well matched with the ignition unit. But, this is just an observation on my part and I don't have Petronix installed on any cars, so can't give any solid specifics or personal experiences.
Oh, one last thing... check that the rotor, dizzy cap, spark plugs and plug wires are correct and all in good condition, gapped properly, etc., before going too deeply into setting the timing.
Have fun and welcome!
/ubbthreads/images/graemlins/cheers.gif
bobh
Jedi Warrior
Offline
This link has an interesting write-up on timing advance and retard. There is a note at the end concerning the 69 TR6.
https://www.tr6web.com/Documents/tr6/advretard.html
https://www.tr6web.com/Documents/tr6/advretard.html
G
Guest
Guest
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[ QUOTE ]
I think it should have about 9.5:1 compression ratio.
[/ QUOTE ]
I think it was 8.5:1
Bill
I think it should have about 9.5:1 compression ratio.
[/ QUOTE ]
I think it was 8.5:1
Bill
Alan_Myers
Luke Skywalker
Offline
[ QUOTE ]
[ QUOTE ]
I think it should have about 9.5:1 compression ratio.
[/ QUOTE ]
I think it was 8.5:1
Bill
[/ QUOTE ]
Ya got me curious so I had to look it up in the Bentley manual.
You're right. The pre-1972 USA/carb TR6 were 8.5:1. That was dropped to 7.75:1 in 1972 and later cars.
I was mixing it up with the P.I./European cars, which were 9.5:1 throughout production.
/ubbthreads/images/graemlins/cheers.gif
[ QUOTE ]
I think it should have about 9.5:1 compression ratio.
[/ QUOTE ]
I think it was 8.5:1
Bill
[/ QUOTE ]
Ya got me curious so I had to look it up in the Bentley manual.
You're right. The pre-1972 USA/carb TR6 were 8.5:1. That was dropped to 7.75:1 in 1972 and later cars.
I was mixing it up with the P.I./European cars, which were 9.5:1 throughout production.
/ubbthreads/images/graemlins/cheers.gif
vettedog72
Jedi Knight
Offline
69tr:
I had the same problem with all the ATD etc. and set my '74 with the vacuum blocked off and the motor running about 800rpm to 8 BTDC and it runs pretty good. PS I set it with a nasty old timing light that fires off the #1 plug. BTW, I don't think there is any centrifugal advance at that RPM.
I had the same problem with all the ATD etc. and set my '74 with the vacuum blocked off and the motor running about 800rpm to 8 BTDC and it runs pretty good. PS I set it with a nasty old timing light that fires off the #1 plug. BTW, I don't think there is any centrifugal advance at that RPM.