Talk Morgan Forums Morgan Sports Cars Morgan Three Wheeler & Super 3 Stubborn start M3W

Reflash the ecu?

Wait, reflash?

Only if you have an unlocked (ie aftermarket) ECU.

I would be losing sleep thinking about this, you have my sympathies. I take it that the Protune diagnostics drew a blank?

Try checking the cam timing - if the camshaft drive belt has somehow slipped a tooth or the drive sprocket has slipped this could cause difficulty starting.

Another slightly off wall suggestion.

Have you tried starting with accelerator half depressed?

I had issue with startup and idle, but higher rom was ok.

Turned out to be the ECU wrongly firing injectors it’s twice per cycle, but only at low rpm!!!

I have also had issues with delamination of the flexible fuel lines leading to and from injectors which intermittently caused issues. Not at same time as above

Clutching at straws, comes to mind

I believe it can be sent to Morgan for a reflash.

"Have you tried starting with accelerator half depressed" According to the handbook you should not operate the accelerator when starting. I believe there is an inhibit on starting if the pedal is pressed. Would do no harm to check the injector wiring & connectors are clean.

At idle is it smooth? Or not?

Check timing belt

Back again after many days. One of those days was spent with the S&S authorized mechanic in Pendleton, OR. He spent at least an hour of his time on a wireless headset with "the guy in Wisconsin." Tested seemingly everything and had to push start me at the end of the day to get off the lot.
Another day was spent with a H-D dealer 50 miles away in Kennewick, WA. These folks actually found a Morgan dealer who would answer the phone. He was all the way in Florida but was most cooperative and earnest. He sent a wiring diagram by email of the ignition system. The mechanic pronounced it vague, said it lacked any color code. Six hours later he and his boss pushed me down the hill and I drove home in the same shape as when I began only $814 bucks lighter in the wallet. Here are the mechanic's notes from the H-D shop because I know you all just love puzzles.

Fuse block missing two fuses
Found bad fuel pump relay replaced relay still no power to relay
Installed 15 amp fuses in missing slots and got power to one of the relays not the fuel pump relay.
Found 10 amp fuse blown replaced no results
Fuel pressure is 55psi
Tested injector trigger and its good
Good spark proper gap
.016 VDC at crank position sensor
.000 volts at crank position sensor at power up
.056 volts at crank position sensor when start button pressed
Left cylinder at 10 psi, compression right cylinder at 25 psi
Bad crank position sensor and lack of compression will usually not allow spark but this machine has good spark
Can bump start which is unusual for a Harley motor
Faulty ECM?
Fuel pump relay could be dropping signal
All ground straps tight and good connections

I'll only add that with such compression the engine should not start at all yet it did and got me the freeway 50 miles home.
The only noticeable change from all this is that the fuel gauge is now accurate for the first time. It was always 50% off before. Another little Morgan idiosyncrasy of the sort that is quickly losing its charm these days.