Petrol Injection rebuild

[Thorsten]

Hi Ian,

Yes, pulling the lever towards the front of the car is what the choke cable would do. Regarding LHD choke cable: IIRC A garage once replaced the broken choke cable on my LHD Mk1 PI by something out of the MG spares drawer (possibly with some fiddling about). Maybe it's worth checking what MG cables look like?

Best regards
Thorsten

[Alec]

Hello Ian,

it does take a lot of cranking (Which is why the manual says a fully charged battery is required) with full choke. It is not a choke in the sense of a carburettor which blocks the air flow but a lever that opens the fuel cam and significantly incresaes fuel delivery. If you look down on the metering unit you should see a small lever to the rear and on the engine block side. This really needs to be fully forward when doing an initial start. In all the years I've had a P.I. I've nevr purged the injector lines, it's not necessary.
Are you checking the fuel pressure at the pump or at the metering unit, the reason for the question is if there could be a restriction in the supply line. If you crack the union where it enters the metering unit you'll see if there is fuel pressure or not. (No smoking:-)?

Alec

[Charles H]

There are two cables to the choke pull on a PI. One goes to the throttle linkage to increase revs. and the other to the overfuel lever on the MU. The former is not really much help since it usually makes the engine run too fast and can be done using the throttle pedal. The most important one is the overfuel lever on the MU. Make sure this is actuated and crank the engine using the existing well charge4d battery and jump leads to another 100% one. Persevere, it will run.

[Ian3781]

Thanks Charles, news soon I hope

[Richard B]

I have found it useful to refill a drained (empty) system.

Take the spark plugs out of the head and disconect the ignition system at the LT on the coil.

This enables the starter motor to crank the engine over with less effort from the battery. A Hi-Torque starter helps even more.

[Ian3781]

Thanks to all who read and replied.

I found a mechanic not too far from my home who has considerable experience with P.I. engines (extremely rare in France these guys)

He applied his experience to what usually prevents it from starting, and he has succeeded. I don't know details yet, but he mention "clapets" which I think translates to non-return valves in the outlets of the metering unit which often get clogged up with old petrol.
With this great news, we can proceed to finish a million other jobs and hopefully have this old girl back on the road in 2025.

I'll report back once I know more about his analysis.

Thanks to all
Ian