Er, it's full of petrol

[charlie]

Been up and running for a week now, 400 miles without a hitch.

Only one small problem. I was having a fiddle with the MJLJ the other day, and took the vac pipe off the back (engine not running). A small amount of petrol jumped out at me, so I took the MJ apart to have a look. The vac pipe was full of petrol, all the way up to the MAP sensor. I managed to drain it out OK, and none had escaped onto the PCB, so I put it all back and hooked it up again.

Anyone else had this happen? Is it anything to worry about? Is the petrol going to melt anything (MAP sensor/vac pipe inside MJ)?

For information: 1275 Mini, HIFF44 SU on standard Metro manifold. The MJ is mounted lower than the carb (under dash), and is connected with the old vac advance pipe. Right angle connector at the manifold end, with the take-off on the top of the manifold. The MAP is effectively the sump of the system, so presumably any condensation in the vac pipe flows there.

I did connect the coilpacks up the wrong way initially so the car was firing 180deg out whilst cranking for a while. Could this be something to do with it?
The idle vacuum is a little shakey (45-55kPa), so I was thinking of putting adamping chamber in. Should I just make this double up as a catch tank?

Thanks in advance,

Charlie

[alexander]

> The vac pipe was full of petrol, all the way up to the MAP sensor. I managed to drain it out OK, and none had escaped onto the PCB, so I put it all back and >hooked it up again.

definitely doesnt sound good!

>Anyone else had this happen? Is it anything to worry about? Is the petrol going to melt anything (MAP sensor/vac pipe inside MJ)?
hasnt happened to me; i would think so; dont know, but cant be good for the MAP sensor

>I did connect the coilpacks up the wrong way initially so the car was firing 180deg out whilst cranking for a while. Could this be something to do with it?
sounds plausible, but still also sounds like there is a lot of petrol in there!

>The idle vacuum is a little shakey (45-55kPa), so I was thinking of putting adamping chamber in. Should I just make this double up as a catch tank?
if you only have one carburetor, my belief is that a plenum wont do anything. for my part, however, i did put a mini fuel filter in the vac line to the MJ to block fuel vapours heading that way. it is of clear plastic so wouldnt be a bad idea for that purpose, and so you could see if there was any petrol in the filter.

alexander.

[david jenkins]

I'd suggest that you fit a small petrol trap - a little air-tight pot with 2 pipes in the lid would be fine. Any petrol would fall into the pot and not get into the MAP sensor. If you can find the right sort of pot, you could unscrew the base and empty it now and then.

I'd also consider putting the MJLT unit higher than the carb, so that any petrol would drain back (if that is an option, of course).

Cheers,
David