Home › Forum › Ask A Member › Evinrude model U › Reply To: Evinrude model U
Tom gave some great knowledge! The compression fittings are about .050 undersize. If you use modern versions they will jump thread as you tighten. I made all new ones on the lathe for a ’28 H Fastiwn I built.
The U in my opinion is a lazy starter. By that I mean it seems to start really rich and finally clears out. I’ve always felt the venturi is too big. One day I hope to try a Speedifour carb.
Tom is right on about those cotter pins in the wrist pins. Don’t use a slightly undersize cotter pin because it’s easy to install! Use a full size. I found that some have alignment issues with the holes on the piston’s wrist pin boss and the wrist pin holes. I did one and used an aircraft drill (needed for the length). I lined up the top piston hole with the wrist pin holes and ran the drill through to bring the bottom piston hole into alignment. I have seen 29 U’s using wrist pin clips!