Yes the timing could be causing you to have to keep it at high idle to get any power and cause hard starting. You should be able to pin the flywheel at TDC and see the timing marks on the injection pump after you remove the little cover off the side. With the flywheel pinned and the cover off the injector pump, you should see a couple of lines marked on the internals. Just loosen the mounting bolts on the pump(take a
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