<VV> 140 idle speed

Grant gyoungwolf at earthlink.net
Sun Jan 30 15:18:02 EST 2022

Subject: 140 idle speed - Looking for some thoughts on idle speed for a '65 140. Background: Working to get this back on the road and running well. When Ibought the engine, it did not come with a carburetor linkage. I installedthe Clarks carburetor rotator kit with a progressive linkage. I have 4primary carbs installed.I have the engine running pretty well but the idle speed is high (1000 -1200) when warm. All of the throttle plates are fully closed.I have checked for vacuum leaks but did not find any.The carburetors have new shafts installed.
Having a stock set up or 4 primary carbs does not have any impact on idle speed as you can adjust 2 or 4 to get the same results. Many folks run 4 primary carbs without the rotator kit with no issues, so that should narrow things down. My limited experience installing 4-5 sets of the rotated carbs is that it is easy to get the linkage wrong, and there can be binding due to the limited operating space. There is something out of adjustment, so I recommend to start researching by backing out all the idle speed screws and  disconnecting linkage until the idle calms down (after you confirm that your timing is in spec: too much advance = increased idle speed). The throttle plates can look like they are shut, but not be, and it only takes a quarter turn of the screw to mess things up. If, for example, the throttle plate in the one connected to your vacuum advance is opened past the ported vacuum slot in the base (more than about 2 turns in), you will not be able to get them right. 
The Carbmeister

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