T/D .15 barrel has a nipple like thing on the side

The crankshaft doesn't need to be removed to drill the hole, the crank is used to clear the chip. You turn the window in the crank towards the hole and drill the hole with a small number drill. The crank is then rotated to break the chip. The crank is hardened and the case is aluminum. The chip breaks off and falls into the window and it's removed via the backplate. The problem is that the recommended drill size is still too large. You only need a pinhole size hole about .014". This is known as timed crank pressure due to the pressure line only being impacted when the window passes the hole. It's very problematic and it causes pulsing within the fuel line which in turn makes the engine surge up and down. A one way valve inline on the pressure line helps immensely. My personal feeling though is that you gain nothing but a headache in doing so. You also flood the engine trying to start it. It's only real benefit is that if you open the venturi larger for more power. However, you can only go so large before breaking into the jet holes in the venturi. Now the engine will never work on suction again and a new venturi must be obtained. If running pressure is your only option, I would opt for crank pressure vs the timed crank pressure and this can be obtained by either drilling a hole in the backplate or through the case in the rear of the engine.

944_Jim wrote:..............Maybe I needed different fuel line...maybe I should try my stock of IV tubing. Hmmm.

I've found the tubing on the nasal cannula to be almost ideal for lots of small engine applications.

a--

The nipple has taper on it. Unfortunately , it's in the wrong direction and it more than likely is tapered so that it releases from the injection mold. If your tubing fits now, after fuel and vibrations, it's going to fall off. One solution is to take a 2-56 blind nut or a 4-40 and file off the barbs. Screw the blind nut onto the nipple with the flange facing the carb body.

I should've also mentioned that I use CA on the fuel line and hit it with some kicker. Liberally apply it around the fuel line and hit it with kicker. Fox ,35 has a POS needle valve and the fuel line never wants to stay on so I do the CA thing and wire tie it.

I’ve not had much luck finding discussions on this motor. Are there any idiosyncrasies or advice that might be useful before I built something for it?

FYI, the nipple thingy is ground off my 15.

Thanks!

Dave Mo…

PS: Lately, this site’s search function hasn’t worked on my computer.
D…

DaveyMo wrote:I’ve not had much luck finding discussions on this motor. Are there any idiosyncrasies or advice that might be useful before I built something for it?

FYI, the nipple thingy is ground off my 15. OWCH!!

Thanks!

Dave Mo…

PS: Lately, this site’s search function hasn’t worked on my computer.
D…

The Search function works if you use the one on the Left Hand side and highlight the Google dot.  

Gotcha. So I have a Cox 15 Special and not the TD.

Many thanks!

Dave…