My mini has decided to start surging when going around roundabouts. I go around them at a sensible speed (10-15Mph) and the fuel tank is about half full so I don't think its the fuel pump cavitiating. The whole fuel system is the original one i.e. no electric bits. My idea for the problem is water in the tank. But before I drain the half full tank, has anyone else got an idea?

If you suspect water in the tank dont stuff around looking for something else.
Tanks not hard to drain, you'll see the issue if there is one.

Take the lid off the carby and see if there is any sign of water or crud in the float bowl. There is no point draining the tank if there is no water in it.
Does it surge in both directions? or just turning right?

Low pressure in the fuel system will effect it under load like when you are going uphill. A drop in pressure in a corner is usually caused by float level.

Agree with Morris...no point unless you are sure you have water....more likely a float level or fuel pump problem.

You can dose the tank with Metho if you want to displace water....maybe 500 mls to a tank.

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"Show me the Mini!"

My wifes father has mention this to me also

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Stop Licking the Dog...I Don't Care Who Started It

I've only noticed it surge while turning right. This may not be related but I get a big whiff of petrol too. I've pulled over straight away a couple of times now to look for fuel leaking but can't find anything.

Just run some fuel with ethanol to do the same thing (and more)

Take the lid off the float bowl and see which way the float faces. It should be fitted so the float is pivoted fore and aft, not sideways.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

my brick had done this for a while... turns out i didnt have enough oil in the dash pot lol
maybe this could be the problem??

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