Wisps of smoke, slight kero leakage at fuel tube / combustion pot connection

[catamount]

Well, you guys will remember that I just rebuilt my 422. All is well, except for a hint of kero small. With a flashlight, I could see very faint kero seepage & wispy smoke at the fuel tube connection to the pot. The brass nut is VERY tight and I don't want to over-tighten. This is particularly noticeable when the combustion blower is on high! It's like it's blowing kero back past the capillary tube.

I used a new burn pot, was there an additional "sleeve" from my old pot that was supposed to go into the fuel inlet connection? The "old" fuel inlet (that had rusted free) seems to be slightly smaller than the new one.

[hawkins111]

fuel nozzle insert

Yes, there should be an insert in the nozzle. Your new one may have fallen out when you took the brass nut off. It fits very loose when new. My book does not show a part number for that part on a M422. Someone on here may have an old one for you.

Tom

[catamount]

hawkins, you were exactly right. I went back to my old nozzle and tried to bang out the sleeve and it slid right out with a little persuasion. I put it into my new pot and the smoking / leakage is gone. Thank you very much! I will post photos of it tomorrow so people can refer to it in the future. Anyone replacing their pot will definitely need to be aware that this part gets switched over in the process. Thanks again!

[catamount]

For future reference:

IF YOU REPLACE YOUR POT, be aware of this:

After this rebuild, I noticed some slight kero seepage at the fuel inlet when the combustion fan was on. There is a brass sleeve ("nozzle?")on my original fuel inlet that goes on the end of your capillary tube, and fits tightly inside the fuel inlet of your new pot. I did not know about this sleeve when I replaced my pot, and without it there was a leak / wisp of smoke during combustion.

This was my old, broken off fuel inlet. Notice the sleeve inside. If you are replacing your combustion pot you will have to press this sleeve out and transfer it over to your new pot. I used a bolt the same size as the outer diameter of the sleeve to gently hammer it out.



This is the sleeve once it's out.



This was my new pot without the sleeve. It will leak like this.



This is with the sleeve installed.

[FordMan59]

If I remember correctly when I got a new pot from HHG the fuel nozzle insert was in a small cellophane package inside the box with the burn pot. It wasn't installed in the burn pot. If you still have the box around you might check to make sure it isn't in it or that the package isn't laying around the area where you worked on the heater.