Re: Volvo MD7a
Are you sure that you don't have a very small air leak in your fuel system? From the engine's prospective, there is no difference between sitting for a week and 2 weeks. After a day, the engine block will not retain any heat and nothing should change so starting should be the same provided that your batteries are not discharging.
If you want to test for an air leak, let it sit for 2 weeks and pump the hand primer for a long time before trying to start it. If it starts similar to sitting for a week, you have a small air leak. This will not rule out an air leak in the injection line but it will get most of the likely suspects.