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Triumph TR6 - First breakdown...
|The poor old TR6 has not seen much action this year - its big brother (Stag) has taken its place in the garage and so it was relocated to the in-laws' garage, making it a hassle to get it out for a drive. |
My daughter loves the car and after picking her up from school in it yesterday, she convinced me to drive her to school in the TR6 this morning. To do this, I left the car at home, where it sat outside - first time in my ownership... Went out to find a heavy layer of condensation on the car. Oh-oh, I thought to myself. When we set off, the car started, but wasn't running smoothly. Stalled every time I stopped. Got to school (the last couple of hundred yards thanks to inertia and gravity!) dropped her off, and then tried to start the engine to come home. Easy enough to start, but would not run. I figured the plugs were fouled, or the electics didn't like the condensation. Of course, I just cleaned out the boot yesterday and left all the tools at home... I walked home and got some tools, cleaned the plugs, points and such, and got it running well enough to drive home. Choke out all the way, but no sign of a misfire. I figured I would have another go after lunch - sun out all morning so should not have been any moisture left. Started fine, ran fine for about a mile, then stalled and when I restarted it jerked all the way home - careful test route planning meant I was going downhill at the end so I was able to drift into the drive - the engine had stalled again.
Any thoughts what could have caused this? My distributor was rebuilt, as was the engine, less than 2 years ago. Not many miles on it though - I am planning to do the first head stud re-torque this weekend. (Speaking of which, can anyone tell me the right torque value for TR6 ARP head studs, using the ARP lubricant? Oh, and for the re-torque, do I loosen all 14 nuts in sequence then retighten them, or one at a time).
I expected to see the plugs fouled, but they were actually a reassuringly dry browny-grey. Or maybe grey-brown, I couldn't tell. Points were a little wider than 0.015, but not much, and I reset them before the latest misfiring. I have a Pertronix ignitor kit which was given to me as a present nearly 2 years ago - I was also planning to install that - would that help, or should I get the points working first?
Carbs were rebuilt (by me) a couple of years ago, and while they aren't tuned to perfection the state of the plugs suggest that the mixture isn't a million miles out. Maybe a hole in the diaphragm? I will have to check that.
Any help and advice would be welcome.
|Did you dry out the diz.?|
|Yes, distributor all dry now, but still no smooth running. |
I checked the carb diaphragms - no problems there. Some oil lost from the dashpots, but surely it would still run, wouldn't it?
Just spent a bit of time trying to reset the timing and now I have managed to prevent the engine starting at all... Oh dear.
Is there any way to test things in the ignition circuit without just replacing them? I mean the coil, condensor, leads... Anything else?
Check the fuel filter!!
|If you find the fuel filter clogged with rust you will have to refurbish your petrol tank. To avoid rust you should fill-up the fuel tank when storing your car for a longer period.|
|Hmm, fuel filter. I must admit I ruled that out without checking because the filter is only about 200 miles old. As I recall I failed to fill up before the car went away for last winter, so certainly a good idea to check that - of course I fell into the trap of buying the metal-case fuel filter (described as beautiful so many times in so many late night e-mails from their supplier), so I can't see if it is dirty or clean inside... I suppose I could cut it open, but that doesn't help if it is clean... This reminds me of the high tech way scientists have found to work out how old a tree is - simply cut down the tree and count the rings...|
I will check the fuel filter and make sure those new fuel hoses haven't started to fall apart, while I am at it. I hope that it is something fairly simple like that!
After messing with the timing last night I know I am way off where I should be. According to Advanced Distributors, I should be 10-14 BTDC at idle, but if I can't start the car (and don't have a timing light) what static setting should I use? I have mechanical advance only (no vacuum advance or retard). The only way I know to set the timing is to put a light between the distributor terminal and the battery and twist until the light just goes out. I seem to recall that the advice is to go with a certain amount of advance, even though the manual says 4ATDC? Does that sound right?
Thanks for the help
|Ignition usually doesn't go wonky that suddenly, and if the plugs are clean it does lead one to think fuel. The symptoms are consistent with fuel pump failure. If you pull the fuel line at the carbs and turn the engine over, you should get an idea as to whether fuel is getting to the carbs. Remember safety, since the starter is close by.|
|A. J. Koschinsky|
|Alistair- There have been fuel pump problems of late with faulty products even C. Runyun has fallen victim to bad parts ,kind of Ironic really.|
|Alistair-The way you put the title,your expecting more?|
Well, I wouldn't be surprised if this wasn't the last breakdown! To be fair, a nearly-forty year old car is unlikely to be the most reliable transport, and when you remember that it was built by disgruntled Brummies in the mid-seventies, reaching every destination under power looks even less promising! In my case I have tackled everything but machine shop work myself, rarely starting a job wihtout the thought "I'll have a crack", so I will admit to being more surprised by the lack of breakdowns to date than I am to have broken down now!
If we can't laugh and be grateful that the TR6 is fairly easy to push we probably shouldn't be doing this, right?
|Okay, I am back to where I was the other day. Car now starts easily, runs until warm and then starts to stutter. Stuttering continues with the choke in or out, and reduces at higher revs. There is also a slight hesitation between opening the throttle and revs building.|
I retorqued the head (all nuts turned maybe a flat), reset the rocker arm clearances (some were a little tight, I guess the valves are bedding in?), reset the timing to 12BTDC static, checked that fuel was flowing freely (it was, but when I find that spare fuel filter I will replace the old one), and reset the point gap - foolishly on Thursday I reset it with what turned out to be a metric feeler gauge, so the strip marked "15", which I thought was 0.015 inches, turned out to be 0.15mm. It started and ran the other day with the very small gap - in fact the gap was smaller that 0.15mm when I first checked it.
I think I will try replacing the condensor and then the coil, just to see if either of those help. Then the Pertronix kit will probably go in (if the missus doesn't come up with something more productive for me to do before then!).
Thanks for the help
|Looks like it was the condensor. I just got back from a long test run and it runs very well now. So well that I have put off the electronic ignition again. Maybe I will regret that...|
Thanks again for the help.
|"Car now starts easily, runs until warm and then starts to stutter."|
Alistair. My 76 had the same symptoms and upon a cold start, early idle and initial drive all ran very well. When warm to hot the exact same events happened. The new distributor cap I had installed was defective but I overlooked that in my diagnostics because it was new. Bad move on my part... it indeed was the distributor cap.
My 2 cents worth...
This thread was discussed between 03/09/2009 and 07/09/2009
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