My Scrambler starts perfectly when cold.
Even at very cold temperatures.
When the engine is hot the start motor struggles to crank the engine.
It gives the impression that the battery is flat.
This isn’t the case. If I let it cool down it starts perfectly again.
Very annoying problem, every time I stop for gas with a hot engine (+90 degrees)
I have to fear if it starts again.
Fresh YUASA YTX20HL-BS battery installed
Starter motor refurbished with fresh brushes
Any ideas what may be the cause of this problem?
Is it a known problem for the 1200cc Morinis?
The Forum was down a few days for an update.
The problem you describe isn’t a known problem to me.
Normally the engine starts without touching the throttle. Have you tried to accelerate a little bit during the starting process. Does this change anything?
Do you have the possibility to do diagnostic on the ecu. Check the throttle position sensor it should be around 2.7.
On the left side under the Airbox is a round cable connector. Check the pins for corrosion or humidity. Is the temperature indication in the dashboard correct, also outside temperature.
Use the software to check the air pressure value. Maybe a wire is broken on the right side of the steering head.
If the starter motor has problems to turn the engine its also possible that the decompression unit of the camshaft isn´t working when the Engine is hot
Maybe you can check this measuring the motor compression.
If there is a problem with the decompression unit the compression should be different when then the engine is cold (low pressure) or when its hot (high pressure).
- camshaft.JPG (48.19 KiB) 491 mal betrachtet