I am rebuilding a NH for my 27. I just need to get the vaporizer off, its typical been rebuilt by to many people and runs terrible and to hard to start. Compared to my other NH. My question is should i drill out the plugs in the carb body or should i just clean with wire and carb cleaner? Tim
Depends, How badly are the ports plugged? You could try cleaning the body by soaking and then rodding the best you can. Try the carb on the engine and see how it works. Otherwise drill the plugs out and tap the holes for new plugs. There are pictures here on the forum.
Mike, I will clean them out first and try that. I did look up the old thread about drilling them out. I would rather spend some time cleaning before I drill the plugs. Thanks Tim
Tim: FWIW, Use of a #4-40 tap and correct drill allows you to thread the brass plug and pull it with a 4-40 screw and not enlarge the hole in the cast iron body. I mention this b/c a post was made here a week or so ago to use #6-32 and I found that screw to be too big for brass plugs in the NH. From my experience this past week, I recommend pulling the plug in the carb flange first and carefully clean that passage and the two holes near the throttle plate. If that passage is clear and you spray cleaner into the passage and down stream resistance is not apparent, stop there. The other two brass plugs are removable, but I'm not convinced the benefits are worth the trouble. I see absolutely no reason to molest the brass patent tag b/c the passage beneath it is easily accessed from inside after removing the spray needle seat. respectfully, jb
James, thanks for the advice on the carb flange plug and will try that. I normally have good luck with zenith carbs for Model A s but these are so different i need everyone's advise. I dont really want to have to take it off and on if i can do it right to start with!! I love being apart of this forum because of all the experience and knowledge of the members.... Thanks Tim
Aerisol carb cleaner with the mini straw nozzle. Just blow through every hole. You'll know soon enough if any thing more drastic is needed. Cheap & easy. Wear goggles.
I have used brake cleaner..Works good for me.