MG-Cars.net

Welcome to our resource for MG Car Information.

Recommendations

Parts

TR parts and Triumph parts, TR bits, Triumph Car Spares and accessories are available for TR2, TR3, TR3A, TR4, TR4A, TR5, TR6, TR7, TR8, Spitfire and Stag and other TR models are available from British car spares and parts company LBCarCo.

Triumph TR6 - misfire at around 3000 RPM

We were out driving tonight, pretty hot night about 90 deg. I noticed a misfire under load at around 3000 RPM.. No misfire when revved up no load. The misfire only became present when the engine got hot. The temp gage was only about 1/4 way up. The idle became low and lumpy and a restart was very long and labored. I haven't had a chance to look at anything and was wondering if anyone has any ideas where to look first. Maybe someone has experienced this. Seems like it could be fuel related but that's just a guess now.

Thanks
Henry
HP Henry Patterson

Henry,
Pull your plugs. Sounds like a fouled or broken plug to me.
db
Doug Baker

If you have a points-type ignition, you might want to try replacing the condenser. It's a cheap fix, and I have had it fail very much like that.

Tom
Tom Note

Check your plugs. They might be Whitish in color. I'm thinking that when your car gets hot, your temperature compensators are wide open which is leaning out an already lean situation making it misfire.
If it's lean, it misfires consistently and your plugs are whitish. If it's rich, the misfiring is not consistent,it smells like gas, and your plugs are black.

Here's a couple websites to read:

http://www.sterlingbritishmotoringsociety.org/files/CarbsII.pdf

http://www.sterlingbritishmotoringsociety.org/files/CarbsIII.pdf
Regards,
Benji
benji

Thanks guys,

I'll start with the plugs and see what they tell me.

I forgot to mention that I have a pertronix ignition system.

Henry
HP Henry Patterson


The plugs are black and sooty. I'll replace the plugs and lean out the carbs about 1/4 turn each and set the timing. Hopefully that will help. I'll let you know.

Henry
HP Henry Patterson

It looks like the plugs took care of it mostly.. Thanks Doug, Benji... Good call! I found the timing to be way off too. It was just a couple of degrees past the TDC mark with the vacuum advance hose pulled and blocked. I thought it felt a little flat.

It seemed to run a little cooler this evening. My wife's feet didn't cook to the floor. Maybe my retarded timing was throwing extra heat down the exhaust.

We were out on Woodward Ave tonight. A lot of you know about the big "Dream Cruise" that officially starts next weekend but unofficially started today. A lot of cars out. Many of you might think it's all American muscle but really there is a huge variety of classic's, of course predominantly American. I even saw a Model A and an original old Dusenburg..nice. There were plenty of British classics as well. I saw a few Austin Healey's, some MG's, and of course Triumphs. I think I was the only one representing the TR6 though. Got a lot of thumbs up. I even saw an old Rolls Royce and an Aston Martin. Great fun. You should try to make it here sometime... All of you.

Thanks for your help

Henry
HP Henry Patterson

This thread was discussed between 02/08/2007 and 11/08/2007

Triumph TR6 index