TR6 TR6 starting problem

[backroadsjeff]

Hi All,

I've been away from the board for some time because all the LBCs have been running excellent. I recently had a tune up done on my '73 6 and it was really smooth and good power. Drove it almost constantly for a couple of weeks, and had a number of 30mile 70mph runs. After these the car ran rough. Starting the next days got progressively worse with farting, and misfiring. Would eventually smooth out and run well. The last time I drove it the car started misfiring right after a high (4000 rpm) run then settled out. Car will start, (run really poorly) then die. I'm suspecting fuel rather than spark and I'd like your opinions....

Jeff

 

[DrEntropy]

Sounds like fuel from the description. A "flow test" of the pump would be first order of business, then carbs inspection. Have you a filter between pump and carbs? Might change that just for grins...

 

[Tinster]

Have you a filter between pump and carbs? Might change that just for grins...

Pondering my past month's painful repair efforts due possible fuel
delivery problems causing the high rpm misfiring, backfires, engine
falling apart over idle speed, etc

........................just for fun

I'd replace the dizzy condensor first- since it takes the least amount
of effort compared to everything else. If you have electronic ignition-
begin the fuel side diagnostics.

 

[Trick6]

If the problem remains after replacing the dizzy condenser, I would go right to the old "trash in the fuel line." Try removing the carbs and float bowls. Clean everything out and blow dry with care using compressed air. Check the float heights. Replace the float bowl gaskets and reassemble the carbs. While you have the carbs in hand use a lot of Carb Clean and spruce up the outside surfaces. Change the fuel line filter then before you connect the fuel lines to the carbs, spin the engine (without the plugs) to clean out the trash possibly lingering in the gas line from the pump to the carbs. Then put it all back together. If that is not the fix, you will at least be clear that it is not a dirty fuel problem.

 

[backroadsjeff]

Thanks to all for the inputs and suggestions! Hopefully I can get this resolved this weekend. I report back on my progress.

I had a similar issue with my '78 Spitfire. The fuel line/filter kept clogging. I ended up replacing the fuel tank. (not as dramatic in that car, engine would just stop)

Have a great 4th!

 

[backroadsjeff]

Well things are not going as well as I had hoped...The condenser is new (tune up last month, new diaphragms in the carbs etc.) I was able to get it started yesterday after checking the fuel flow, spark, gaps etc. and once it was running ran pretty well. For fun I decided to clamp off the fuel before the filter to simulate a blockage; car ran fine then died as expected but not the horrible sputtering and convulsions as when starting. drove it for a while ~ 15miles and save for one early stall had no problems. it Started right up after the stall. Decided to not take it to the shop as there was no one there anyway so I left it in my garage. Again this morning it refuses to stay running...It seems temperature related. Also tried swapping batteries to see if maybe the voltage was a bit low. No change...

I'm stumped - any suggestions???

 

[Tim Tucker]

Swap back to your old rotor button.

Your symptoms sound alot like mine from a bad rotor on my TR4. It takes seconds.

Good Luck,
Tim

 

[GreenOne]

I had a similar problem as you describe with my 6 recently, and after going through all the motions, fuel, coil ect, it turned out to be a bad rotor, which by the way took it's toll on the cap also. After changing everything out for new no more problem !

 

[tdskip]

I'd start with rotor and condensor as well.

The temperature related thought promopts me to ask what condition is your coil in?

 

[tom628]

I've also had problems like that with rotors. I've also had a newly installed condenser fail after a very few miles; like 10 or so.

Tom

 

[Tinster]

I've also had problems like that with rotors. I've also had a newly installed condenser fail after a very few miles; like 10 or so.

Tom

<span style="color: #990000">Wow!! That's not very encouraging, Tom.
I was thinking about ordering 5 spares. I think I'll
increase the order to 10, just to be safe.

dale </span>

 

[backroadsjeff]

Thanks guys - I charged the battery last night, hoping it would be that as I had run the battery down trying to start it. While I was running today I decided to go back to basics:
- Fuel flow is good although with the gas pains of late I might have a "special" blend as the last fuel was not from my standard station...
- turn the car over to see if the charge helped - no
- Static timed again - not far off but reset anyway
- Checked the spark - although present very weak.

Don't have the old rotor as I didn't perform the tune up and I don't have another condenser handy. I think I'll get a couple of new ones and try it again.

I'll keep you posted as to my progress....

 

[DrEntropy]

- Checked the spark - although present very weak.

Have you cleaned the points with #400 or #600 abrasive? You could get a condensor at NAPA just for "drill", too.

 

[Guest]

Do you have a spare coil laying around? How old is your coil? Check <span style="font-weight: bold">all</span> the wires going to it, they get brittle over 30+ years. Coils seem to last forever...until one day.

.

 

[backroadsjeff]

Do you have a spare coil laying around? How old is your coil? Check <span style="font-weight: bold">all</span> the wires going to it, they get brittle over 30+ years. Coils seem to last forever...until one day.

.

I believe the coil is original to the car - I agree the wires going to it are not in the greatest of condition. Those will be corrected. Sadly I don't have a coil lying around, but as you say they seem to last forever...

Thanks for the recommendations!

 

[tomshobby]

I've also had problems like that with rotors. I've also had a newly installed condenser fail after a very few miles; like 10 or so.

Tom

<span style="color: #990000">Wow!! That's not very encouraging, Tom.
I was thinking about ordering 5 spares. I think I'll
increase the order to 10, just to be safe.

dale </span>

Last week I went down to my local Import part store and got a new cap and rotor. Cap made in Germany and rotor made in Italy. Was nice not getting that Asian junk. Oh, I was replacing the same that were starting to show signs of age.

 

[backroadsjeff]

Have you a filter between pump and carbs? Might change that just for grins...

Pondering my past month's painful repair efforts due possible fuel
delivery problems causing the high rpm misfiring, backfires, engine
falling apart over idle speed, etc

........................just for fun

I'd replace the dizzy condensor first- since it takes the least amount
of effort compared to everything else. If you have electronic ignition-
begin the fuel side diagnostics.

I'll never doubt the board again! I replaced both the rotor and condenser and voila problem solved - I replaced both at once and so don't know exactly what was the cause, nevertheless, the condenser was unmarked, and I replaced it with the new one that was marked with "Lucas" so I'm suspecting that. I will go back and validate which one was the culprit and let all know.

Thanks again to all for the assistance!

 

[GreenOne]

Take a look at the old rotor, is the brass contactor loose or wiggly, when mine went it had about 300 miles on it and no way could you tell by looking at it. I didn't realize it was bad until trying to put it back when I felt slight movement in the contactor. It did not take much play to stop the car dead.

Glad you were able to resolve the problem !

 

[Tim Tucker]

Too bad we'll never know the culprit...

Very Glad you fixed your TRIUMPH!

Tim

 

[backroadsjeff]

Too bad we'll never know the culprit...

Very Glad you fixed your TRIUMPH!

Tim

I went back and put the old rotor in the dizzy, cranked it over and it runs fine so it definitely was the condenser. Live and learn!