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Triumph TR6 - Little help with tuning

First I wil give you the details doing a total restoration. Car has not run in 2 years spent winter working on engine and all under binnet areas. Two years ago after I first got the project spent time and new parts getting motor to run. New fuel pump, points rotor and rebuilt the carbs. I have been able to start the car and at first it would run only with choke on, that seems to be getting better now it back fires through the carbs like a old smoker hacking up a lung. Had the distributer out could this be timing or is it the carbs. Found one problem last night I had set the carbs aside while I had the motor apart and all of the dashpot oil had drained out. I am far from my wits end but want to make sure I am thinking of everything.

Distributor could be out 180 degree's? From your description most likely.

Carbs may not be assembled properly? The O ring in bottom of dashpot is your oil leak likely.

Do you have a manual? If its Haynes re-read on the 180 checking the pictures. Confusing

This sight has a whack of info on the Carbs.

Kind of in a hurry sorry

Let us know where your at?

Bill Brayford

Dave-I hate to mention the obvious, but is the gas fresh? My Tr3 used to run like crap until fresh gas was added if it had been lying dormant over the winter.

Bill has probably hit it dead center.
My rear carb would lose all it's oil after running a very short time. Pulled the top off, removed the needle and poured a bit of oil in the top. Reinserted the damper and watched the oil run out the bottom of the air valve. If you go to the Overhaul section, Part II at the URL provided by Bill in the previous post, scroll down til you see 'Overhauling the top of the carburettor'. You will see a diagram of the air valve, and the failed o-ring, and directions to replace it.
Good Luck!!

Rod Nichols

Thanks for the input so far. I thought that the distributer might be 180 degrees off because that happenned to me once before on a different motor. Always hard to believe when the engine will run, but very poorly. Filled the dashpots two days ago while troubleshooting this but have not chech to see if they have leaked. Meant that they leak their oil while they were actually sitting on their side. Set the timing up by first removing the first plug, plug the spark plug hole with a good wad of paper then turned the motor over with starter (coil wire removed) one click at a time until compression blew the paper wad out. then put the distributor in with rotor facing the number one spark plug. How can I detrimine if it is off by 180 or should I just use a different method of intial setup. Thanks dave

If you replace the o-ring I would not fully follow the directions as listed above. I have posted a past thread on a "personal correction" to that thread. If you follow the above procedure you will certainly score the inside wall of the air valve where the damper goes in. If you want to replace the o-ring let me know and I will look up the link...I think I even have the correction as a word.doc file.
If the oil drained out then most likely the o-rings are history. Bill sounds correct on the 180 thing and then you will need to start with static timing then the timing light. Since you have rebuilt the carbs, they will definitely need synchronizing. Another area of consideration is valve timing/adjustment. Like Berry said, start with fresh high octane gas...94 if you can get it (Shell).
Keep us informed and good luck.
Rick C
Rick Crawford

Hi Dave

Most reliable way to find compression stroke TDC on 1 is remove valve cover and watch valves both closed rockers up. Enlist some help and try to do it manualy without starter. Crank bolt with all plugs out is usually best. Then check dist. and damper mark. I don't know what all has been done but this should bring you close. If alls right you have eliminated ignition timing problems.

Did you replace your timing chain? If the chain is badly worn or has jumped a tooth you will get same symptoms? Fairly hard to check without major tools. And getting exact TDC.

Have you seen this engine run well? What was your starting point?

Try that and let us know.


Bill Brayford

Good night last First I did check the timing by removing the valve cover and watched the valves. Brought# 1 piston to tdc with both valve closed, then adjusted crank to advance marks. Then discovered that the clamp on the distributor could also be losened to provide more movement. Then set dwell angle with a volt-ohm meter set on resistance test instead using a 12 volt light because I was to lazy to rig something up. Also, the front carb was leaking gas, so I removed found the float valve filled with junk and cleadn as well as the rest of the bowl area. Re-assembled and started up, motor sounds great. Have some questions about the dashpot oil. When I un-screw the cover and look into the hole, where should the level of oil be. Also, what is the best idle rpm setting. I realize I will have to re-sycn the carbs and tune but the motor is really running great right now. Car is not in a state to be driven to give real teat. Wanted to get motor work finished before I finish body work and paint THANKS TO EVERYBODY. dave

The oil should be 1/4" below the top of the air piston in which the damper resides, NOT 1/4" below the top of the cover assembly. The top of the air pison is roughly about an inch down from the top.
Brent B

Hi Dave,
I just finished balancing my carbs and setting the timing, the idle sits about 850-900 rpm and is very stable and nice sounding..sometimes when I slow down at a light I think it stalled !. Also make sure you have good steady vacuum ( About 17 if you have a gauge) I think the manual recommends 900 rpm but I could be wrong !! Bill...I think I'll take a drive your way on Sunday of the long week-end if you'll be around.
Charlie Ballard

Good stuff Dave its all the little stuff that screws things up.

Hey Charlie: I plan to be? Mail me closer. Look forward to seeing you.

Bill Brayford

This thread was discussed between 07/05/2003 and 10/05/2003

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