11 replies to this topic

[purple_fly06]

Hi,

The problem i am having has only just started but seems pretty bad:

The mini is fine on the flat (accelerates...) but as soon as i start going up a hill the car slows down, the revs dies and if i push the throttle down they die even more (i am struggling to get 25mph up most).

Is this a problem with the gearbox, carb or is my fuel pump knackered?

Any answer much appreciated

Thanks

Josh

Edited by purple_fly06, 27 April 2012 - 10:01 PM.

[Ryang556]

Does it ever do it when you put your foot flat on downhills or flat?

[purple_fly06]

no it doesnt, only going up hill

[Ryang556]

Sure you have enough petrol in it... haha

[MiniElliott]

I had a similar sounding problem. When I went up hills the car wouldnt run perfectly and as soon as I grabed 4th it would just judder and loose most power. Turned out to be the valve clearences set too tight. It might not be what you have but its worth looking into before you replace anything.

[dklawson]

As for what to replace when you get to that point... look along the fuel line from the tank all the way to the carbs and replace any fuel filters you find. Also replace your air filter.

[The-Womble]

I had this issue with mine, ran fine on the flat, but as soon as I started climbing hills it would just die. Ended up having to take massive run-ups!

Replaced my fuel pump and it solved the problem. Don't forget to replace the gasket if you do end up changing the pump! :)

[purple_fly06]

Sure you have enough petrol in it... haha

Haha, im not that tight

I had a similar sounding problem. When I went up hills the car wouldnt run perfectly and as soon as I grabed 4th it would just judder and loose most power. Turned out to be the valve clearences set too tight. It might not be what you have but its worth looking into before you replace anything.

I will have a look at that this morning, thanks

As for what to replace when you get to that point... look along the fuel line from the tank all the way to the carbs and replace any fuel filters you find. Also replace your air filter.

I will try the clearences first, then fuel pump and if the worst comes to the worst i will replace the fuel lines... Cheers!

I had this issue with mine, ran fine on the flat, but as soon as I started climbing hills it would just die. Ended up having to take massive run-ups!

Replaced my fuel pump and it solved the problem. Don't forget to replace the gasket if you do end up changing the pump! :)

I have a feeling it is the fuel pump, but i will mess around with the clearances and give it a run, if that doesn't work then i will replace the pump (which should hopefully work) Cheers

[dklawson]

Why do you believe it is the pump? If it is the original SU pump (electric or mechanical) they typically work... or don't work. You have a situation where it sure sounds like fuel starvation under high loads. That suggests an obstruction that is limiting fuel flow.

Starting with a complete tune up (that includes ignition, not just valves) is a good place to start. Follow that by replacing the inexpensive bits like filters. Save the fuel pump for last as they represent more work and money.

[purple_fly06]

I have a spare mechanical fuel pump lying around, and i have replaced all of the filters.

When i rev the car and ease off i can see air bubbles going back up the line... suggesting the diapram in the pump has split??

[dklawson]

The bubbles are curious but if there were a diaphragm perforation I would expect to see bubbles all the time, not just when the engine is decelerating. I would also expect to smell gasoline in the crankcase. How does your engine oil smell?

Since you have the spare pump it would only be an investment in time to install it. That's much better than buying a new pump and finding out later you didn't need one. Let us know what you find out after swapping pumps.

[carbon]

^{Had a Clubman Estate with very similar problem, would go great on flat but struggled when going up a long hill.
Turned out that someone had replaced the ventilated fuel filler cap with one with no vent.
If the air can't get in to the petrol tank then the petrol will struggle to get out...}