Power Loss

[vwroyd]

Hi,

Tonight I was driving along a duel carriageway at about 65mph when I lost power.. I thought I had run out of petrol and had a gallon on me so I put it in.. When it started up it back fired and chuffed some smoke.. I did manage to pull away but when I was driving it only seemed to run smoothly on the second choke and when driving slowly or on first choke it have no power and occasionally pop bang and splutter..

Any thoughts??

Thanks
Chris

[Shaundon]

crud from bottom of tank getting into fuel pipe/ filter?

are you getting a good flow to carb ? Come to think of it what engine is this....

[ghost123uk]

Is it making any smoke now? If so, what colour is it? (you can answer bluish grey or black or white )

Have you checked all the little vac pipes on the carb?
Check the vacuum hose that runs from the left hand side of the inlet manifold to the bulkhead (note = it is a special type of pipe)

[CovKid]

Also, please make sure your engine type is in your signature. Its saves having to resort to a crystal ball.

[vwroyd]

Hi All,

Thanks for the replies... I don't think its crud from tank as I have flushed this and since ran out of fuel topped up and it's been fine.

The smoke was only on initial start up.. A Pop, Bang and Puff of I would say Grey smoke..

When you say what engine type?? Do you mean a code or is 1984, water-cooled 1910cc enough information??

Many thanks
Chris

[CovKid]

Yep, that helps. Thanks.

Undo the petrol pipe to carb and using a self tapping screw, drag out the cone shaped filter hidden inside the brass inlet. Chances are theres crud in there. At full throttle it can literally starve the carb of fuel. Other than that, its the other filter underneath the vehicle or a failing fuel pump.

[ghost123uk]

Ah Ha, CovKid letting his powers of observation slip he he

Chances are there’s crud in there <cone filter>. At full throttle it can literally starve the carb of fuel. Other than that, its the other filter underneath the vehicle or a failing fuel pump.

it only seemed to run smoothly on the second choke and when driving slowly or on first choke I have no power

[vwroyd]

Hi,
Thanks for telling me about the cone filter in the fuel line.. I will drag that out and clean it up.

The problem is definitely with the first choke, it picks up and pulls fine on the second choke..

Do you guys agree that this is a fueling issue?? If so, could the carburetor be past its best,??

Would there be any advantages with fitting a Weber Twin choke or not?

Thanks
Chris

[CovKid]

I wouldn't go to the hassle/expense of changing carbs. Better to get a gasket kit and give it a thorough clean. At the end of the day the stock carb is a good compromise between economy and power. They're very reliable but like all things need maintenance after a time.

In fact the longest job (possibly) is getting the carb off but once it is, its just a matter of checking everything is clear and clean then replace relevant seals/gaskets from the kit.

The clean alone may do the trick (check the bottom of the float chamber for clues) but while its off its a safer bet to have a repair kit. Old seals tend to go brittle if moved, gaskets part company, and you run the risk of introducing air through poorly sealed components. The float valve and accelerator pump gasket in particular can wear to the point of being very unpredictable or even ineffective after a few years. Bits or detached lime scale or grit blocking pathways through the carb won't help much either. Its astonishing the difference a light overhaul can make.

If you have to remove adjustment screws, first screw them in gently, counting the number of turns so you can set them the same on the refit. Bung it all together and hopefully happy days.

[ghost123uk]

Agree with CovKid, no need to even think about a different carb.

Do you guys agree that this is a fuelling issue??

Not necessarily. Have you checked stuff like the advance retard diaphragm on the side of the carb, the plug leads, rotor arm etc etc? Easy to test and thereby eliminate such things before going any deeper.

p.s. the fuel you put in after you might have run out, was it fairly fresh? (or have you added more since?)