LR3

New Member

• Aug 31, 2017

• #1

Had a look in the archive but can not find an answer yet. Cruising along smoothly as you can in a series 3 petrol when the engine missed a beat, then missed more under power with black smoke and backfiring. I can't drive it at all now. Will start, but with miss fires and backfires like crazy. Any advice on how to get it running smoothly again?

 

Turboman

Mab An Gov

• Aug 31, 2017

• #2

LR3 said:

Had a look in the archive but can not find an answer yet. Cruising along smoothly as you can in a series 3 petrol when the engine missed a beat, then missed more under power with black smoke and backfiring. I can't drive it at all now. Will start, but with miss fires and backfires like crazy. Any advice on how to get it running smoothly again?

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Maybe coil? Or ignition timing? Does there seem to be plenty of petrol in the carb? And are there any little blue xmas trees under the bonnet when you run it in the dark?

 

Wimblowdriver

Well-Known Member

Full Member

• Aug 31, 2017

• #3

Are there a hoses from the inlet manifold to the distributor, and brake servo? If they are leaking they can let air into the combustion chambers and the resulting weak mixture would cause misfires and backfires. The other cause of big backfires is air leaking into the exhaust manifold which can help ignite unburnt fuel in the exhaust system.

 

series2steve

Active Member

• Aug 31, 2017

• #4

has it got a weber 34 ,cos the newer ones have a black plastic float filled with chuffin SPONGE,and we all know whats sponges are good at, so do i

 

J

John S

Well-Known Member

• Sep 1, 2017

• #5

X1 replace the coil. Only costs a tenner. If you do have a Weber unscrew the idle jet and clean it/ blow through. Whilst you're doing the coil check the ignition timing. I'd also change the dizzy cap, rotor arm, condenser, spark plugs points and leads. It'll all cost around £35-40.

 

DarrenHS3

Active Member

• Sep 2, 2017

• #6

cant add much other than it sounds like a chronic issue with the carb jets (blockage of air corrector or emulsion tube) need to know which carb you have to advise on that

 

LR3

New Member

• Oct 27, 2017

• #7

Found the problem for future reference. It was the condencer in the distributor. Never expected that.

 

Turboman

Mab An Gov

• Oct 27, 2017

• #8

LR3 said:

Found the problem for future reference. It was the condencer in the distributor. Never expected that.

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Not surprised. Condensers often break down under load. Points ignition is so rare these days that the fact had slipped my mind!

 

Edlandy

Active Member

• Oct 27, 2017

• #9

Glad you're sorted and thanks for getting back and telling everyone the cure.... It helps the rest of us!

 

J

John S

Well-Known Member

• Oct 27, 2017

• #10

A condenser costs about 3 quid. I replaced it, the points, leads, rotor arm , dizzy cap, coil for £40 quid. Money well spent every year or so.