How to hold (fuel pump) gear to tighten nut?

Another option I found online is using a flywheel stopper/locking tool.

 

I haven’t worked on it yet. My fuel pump still works, but I do want to eventually replace it. I’ve watched a few videos on it, and it’s a complicated repair.

I ordered a fuel priming pump that I will need after doing this job. There are cheaper alternatives, but after wasting a couple hours deciding on what to do, I just ordered the one recommended by Detroit (J-47912, part number). It’s expensive, but it’s ready to use. Out of all the cheaper alternatives out there, the better one is to buy a stainless steel sprayer, the compucheck adapter, and possibly some other adapters and a long hose. This one would save you about $125 versus the Detroit recommendation.

 

Yeah, I read about that one, but I think someone said that it’s only good for a few uses.

 

So the method I ended up using was wood and napkins to protect the teeth and my trailer landing gear as a vise. I was getting a little worried about the amount of pressure I was putting on it, but it worked.

Just so everyone knows, changing the fuel pump on a DD15 is a nightmare. This has been the most difficult and time-consuming repair I’ve done. I’m surprised everything came out well, but I took my time to get it done right, and read and reread and watched several videos.