7 replies to this topic

[Gareth_A]

Hi all,

Please would you help me figure out the following (video attached):

1) Turn ignition to on position and weird, repetitive sound starts
2) Turn ignition to start the car, engine starts, and sound continues

Please help me understand what this might be? ...and anything else that your experienced eyes / ears may note?

 

Year: 1973
Model: MK iii

Engine: 998cc

Assembly: South Africa
Video Link: https://streamable.com/ac7j3l

Thank you for your time and assistance.

[Ethel]

Can't hear anything in particular. Noise without the engine running could only really be something electrical like a fuel pump or heater/radiator fan.

[Maccmike8]

Fuel pump. What type is fitted?

[Maccmike8]

Nice car by the way.

[mini-mad-mark]

Is this the fuel pump under the bonnet? Is it rubber mounted? this might be the noise - not sure how much if any difference rubber mounting makes as I've never had a mini with electric fuel pump - others might have something negative to say about rubber mounting and any effect it might have on the fuel delivery - sorry not an expert

 

Just a note your carburettor might be  a "left hand" carb from a twin carb set up  (the float chamber normally on the left of the dashpot looking at it from the front but yours looks to be on the right of the dashpot)

 

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[cal844]

The noise is the electric fuel pump.

I'd move that fuel pump to the rear of the car so it pushes fuel. Then fit a filter and pressure regulator where the pump is currently fitted.

I've run the mechanical pump on my mildly tuned 1275 engine since I bought the car 5 years ago, then only changed it 2 years ago as we had the engine out to do a repair to the engine stabiliser bracket on the bulkhead crossmember. On a 998 engine you only need a mechanical pump, even on a full race engine as they don't need to pump much capacity or flow.

Yes the earlier 45° piped units are a little awkward to use but I find the 1990 onwards mechanical pumps work well as the inlet and outlet are sided.

Edited by cal844, 09 November 2020 - 10:46 PM.

[viz139]

Noise is the fuel pump, its normally located in the rear subframe under the car so you can't hear it. The metal bar from the rad to bulkhead without any rubber mountings wouldn't help with noise either.

[gazza82]

I'd move that fuel pump to the rear of the car so it pushes fuel. Then fit a filter and pressure regulator where the pump is currently fitted.

Unless it is a "pull" pump.