Stromberg Idle Trimming Screw

[4cliff]

The Workshop Manual says that the Stromberg carbs have an Idle Trimming Screw, but doesn't say where it is. Can someone please tell me how to find it.

The exploded parts diagram (Page L 39) in my manual shows lots of screws, but it doesn't answer the question of which is the idle adjuster.

Thanks in anticipation, John

[Frank Howard]

John,

Screw #38 is the one you are looking for. It limits the amount of rotation the throttle shafts can go through when you take your foot off the gas and a spring causes them to rotate back. The shaft for each carb is connected to each other. You must loosen (but not remove) the connection so they rotate independently. Then use a Unisyn to measure the air coming into each carb. Adjust the screws so that each carb is sucking in the same amount of air while the engine is running at the desired idle rpm. When you're finished, tighten the connection. If further idle speed adjustments are needed, you can cheat by simply turning each screw the same direction, the same number of degrees. Good luck.

[fasterbyelan]

It is item 30 of Fig 16, page L38 of my manual. A cross check with the Haynes manual bears this out. The position is near the lower end of the temperature compensator and it looks as if the trim screw has a spring on it.

[Frank Howard]

John,

I'm sorry. Karl is right. I thought you were looking for the idle adjustment screw.

[fasterbyelan]

It is item 30 of Fig 16, page L38 of my manual. A cross check with the Haynes manual bears this out. The position is near the lower end of the temperature compensator and it looks as if the trim screw has a spring on it.

I have physically checked the carbs this morning and the position of the screw is as I suggested.