Morris Minor Owners Club

Is it normal for some fuel to leak / evaporate from the float chamber when the car is left standing?

With my HS4 and even my HIF38 after I leave it overnight, there are 1-2 clicks of the fuel pump. If I leave it for a week, it sounds like the entire float chamber is empty, and clicks about 10 times before stopping. But once it's full, it doesn't click any more.

Is this normal? or are some seals gone?

Fuel does evaporate over time, I get the 2 pump clicks the next day, maybe three or four after a week standing. A fairly common leak point, is the screw bung for the fuel pump filter, as it sits at the bottom of the pump. Easy to check, just run your finger over the bung and feel/smell for a slight leak. I have an HS2 carb, so am not sure if the HS4 has the same connections from float chamber to carb body, another area that can leak on the HS2, is the connection pipe union on the bottom of the float chamber.

Yes - when the engine stops the carb is sitting right above a very hot exhaust - the heat evaporates the fuel. Simple answer - fit secret fuel pump switch (anti theft) and switch it off 100 yds from home so parking up the car with NO fuel in the carb!

bmcecosse wrote:Yes - when the engine stops the carb is sitting right above a very hot exhaust - the heat evaporates the fuel. Simple answer - fit secret fuel pump switch (anti theft) and switch it off 100 yds from home so parking up the car with NO fuel in the carb!

Now I really like that idea

i have got that on my traveller works well