I replaced the impeller on my D4 last January at about 150 hrs. It was in perfect shape, so I’ve kept it as a spare. I didn’t need to disconnect the belt. But I wasn’t able to pull it out manually. I knew about the “bump the starter” technique, but it didn’t work for me (I may have been too tentative with it, and I was doing the work on my own, without someone else to give the starter a bump). I decided to invest in a Sea Dog puller for it, which was a modest expense and is now in my special waterproof box of impeller replacement parts and tools. I rationalized the cost by telling myself if I ever needed to replace it on the fly in bouncing seas, I would want the quickest, easiest means of replacement. For me, that was an impeller puller (as a 67 yr old woman, I’m not too proud to say that my upper body strength is not what it used to be).
My hunch is that the manual says to remove the belt so that the impeller turns freely by hand. Which would make it all the easier to remove and install. But loosening and tightening the belt would offset that benefit. For me, I’d rather leave the belt in place and use the impeller puller to easily and quickly make the change out.
Either way, routine replacement of the impeller is a good drill for maybe having to do it in more emergent circumstances. So I plan to do it annually.
Gini
