1975 135HP Johnson Carb question

[Randyg123]

I was rebuilding my carbs for the first time yesterday (Let the 'pros' do it up until now) and found something unusual. On one of the carbs, when I popped a core plug out, I noticed a gash in the bottom of the well. It looked like someone popped out the core plug with a screwdriver and left a nick. (Not me as I used a round punch ). There are three small holes in the bottom of this well open into the throat of the carb. The nick damaged one of these holes slightly. Can this create any problems?

{I have had problems getting my motor to idle ever since I got it 5-6 years ago. Many of you may recall my posts over the past several years, trying to get this thing working right. Still will not idle well. Electrical system tested within range for all parameters, with some right on the lower end of the required ranges. The only thing I have not done is confirm timer pointer setting (using proper TDC tool), sheered key, and reed status.}

 

[ezeke]

Re: 1975 135HP Johnson Carb question

The small holes lead to the floor of the carburetor throats and need to be clean and open to work properly. Force some aerosol cleaner through the holes and watch to see that the fluid is spraying out into the throat behind the throttle plates.

 

[Randyg123]

Re: 1975 135HP Johnson Carb question

Thanks for the reply Ezeke.

No worries with those holes, they're wide open and clean. I was more worried that one is stretched out a bit more since it was hit with the screwdriver. The hit was enough to make a noticeable bump on the throat side of the carb. But not enough that the bump stood out enough to be noticed earlier. One of those situations where, 'once you knew it was there, it was really obvious'.

Both carbs were quite clean and I was disappointed because I was really hoping for that "Ah-ha" moment when I discovered the culprit for my idle woes. I put in new orifices (30's and 61C's) as well, just to be sure. The old ones looked okay but two (one 30 and one 61) were damaged with partially strip heads (probably from someone not using a proper tool to remove them). But the actual orifices were in good shape and clean.