Misfire in heavy traffic

[CJG]

Hi everybody,

 

The previous misfire has just been solved (electrical), now there seems to be another problem. After about 2 hours of stop & go in 33˚c, the engine has started to misfire, will not rev clealy, and is seriously down on power. According to the temperature gauge, the Kenlowe was just about capable of maintaining an acceptable water temperature, and in any case, the car has just had a new radiator fitted. Does this sound like a carburettor problem (or is it normal behaviour after 2 hours of idling in hot weather)? Can heat affect the ignition system?

 

...or has anyone tried fitting a gas turbine to a TR - should be more reliable!!!

[Alec Pringle]

Hi CJG,

 

for 2 hours of stop and go in that heat I'd want a standard fan plus an electric fan as auxiliary . . . .

 

You have a new radiator, but what about the block ? Have you flushed and backflushed it, and then attacked it with radflush or kettle descaler to shift some of the crud that accumulates over the years ? The block gets bunged up, water doesn't circulate at the back, head gasket blows on no 4 . . . .

 

Also worth checking mixture and timing at low rpm - if either is out, the engine can overheat on prolonged idle. Just because it's fine in the mid and top ranges doesn't mean the botom end of the rev range is OK !

 

Cheers,

 

Alec

[CJG]

Hi CJG,

 

for 2 hours of stop and go in that heat I'd want a standard fan plus an electric fan as auxiliary . . . .

 

You have a new radiator, but what about the block ? Have you flushed and backflushed it, and then attacked it with radflush or kettle descaler to shift some of the crud that accumulates over the years ? The block gets bunged up, water doesn't circulate at the back, head gasket blows on no 4 . . . .

 

Also worth checking mixture and timing at low rpm - if either is out, the engine can overheat on prolonged idle. Just because it's fine in the mid and top ranges doesn't mean the botom end of the rev range is OK !

 

Cheers,

 

Alec

 

 

 

Hi Alec,

 

Thanks for the advice. The car has a Kenlowe auxiliary fan in addition to the standared one. When the new rad was fitted, the block was supposedly backflushed (as the car had been standing for some years). Just a thought though - could it be a vapour lock forming?

 

Regards,

 

CJG