Thanks a lot for the replys!
In last month I did mostly short trips of not more than 50 km.
On this day I did a trip of 100km in the evening. After a break of 1,5 hours, the car was parked on grass, it occurs first time. After approximately 20 seconds it disappeard. After a drive of 15 minutes’ through gentle rain I parked the Morgan outside under a cover.
After Starting the Morgan next day, it took approximately 2-3 minutes until the engine was running normal. Then I checked the oil… It was low, so I refilled 1,5 liter to Max.
Then the Engine was working fine for the trip of 20 km.
Then after restarting, after 7 hours I took this video.
Today I started the engine again , but it sounds a litte bit more normal.
I hope that the problem causes on the moisture or on the low oil level.
Stefan