This is normal... Dont let it bother you if it start anyway.
The cold starting device "shus off" automatically but it do this low revs. So when engine is deading again it activate cold starting device again. And then it shut it off and then activate it again and then shut it.......................
It is possible to adjust the injection pump but its not needed. One way is to mount a Thermostart device to air inlet (there is place in the cast, but there is no hole and threads on it) cast block. I did this to mine 7745 and adjusted the injection pump too. Now it starts much more nice, even -30 degrees cold!