Bosun Higgs
N/A
While I am certainly not defending Eberspacher it is only fair to say that I can't think of any manufacturers who would sell you a service manual. Certainly couldn't see Ford selling Joe Public a service manual for a Mondeo.
You can buy a workshop manual for a car from the manufacturer as I have done in the past. Mikuni will give you a PDF of their service manual FOC if you ask them - they did with me.
I havent had the Mikuni for more than a year though it is 14 years old, but it works very well and without problem. I had a Propex on a previous boat and that worked faultlessly too.