Technical Holley Manual Choke

The manual choke on my 3310 wasn't working correctly, so I bought a whole new manual choke kit, Holley 45-225S. Got it almost done but the fast idle screw would not hit the cam. Found a video online and saw that he installed the screw backwards, with the screw head rubbing on the cam, only way it will reach the cam. It works, I guess, but no way to turn it to adjust without taking the damn thing apart. Here is a snap shot of from the video. You can't see but the screw is barely coming out the other side.


The complete video:


Someone comments that it is indeed backwards.

I emailed Holley tech, there response was, in effect, sorry about that.

I could try a longer screw, just wanted to check in, perhaps we are doing something wrong, maybe someone could take a look at theirs.

 

The fast idle screw works fine on my manual choke 4150. 1300 rpm w/ spring compressed halfway. The guy in the video has the spring and screw on wrong side of bracket arm.



Joe

 

Thanks Joe. The screw that came in the new kit is the same length as the one on my old choke, and appears the same length as the one in the video. 1/2" long not counting the screw head. How far is your sticking out past the linkage?

 

Just added pic. Screw is about halfway in. My initial idle speed is 850 rpm.

Joe

 

Yeah that screw looks twice as long. Guess I'll just dig up a longer screw.

Thanks again Joe!

I think the screw they are providing is for the electric choke kit.

 

No problem. Tried to measure w/ a short steel rule but pretty cramped quarters w/o disassembly. If I get good measurement, I'll post.

Edit: screw shank extends about 1/4" out of arm.

Joe

 

Same as mine from the look of things. Shank protrudes 1/4", slightly less than halfway in. I could back mine off a shade to 1200 rpm.

Joe

 

Joe, is this not part of the screw in your pic?

 

Thanks Mark. I just put it back together again, I can get the screw to hit the cam and raise the idle but only at full choke. As soon as the choke plate moves the cam comes off the screw. Maybe my linkage rod is too short? It's 2-7/8" end to end, with a couple of bends in the middle.

 

Adjust rod as needed.

 

Yes, that's the shank protruding through the lever arm. The full choke adjustment should leave a gap between the choke plate and air horn the size of a #2 pencil.

Joe

 

OK, looks longer than mine and Mark's screw. When I move the lever to full on the choke plate is slammed right into the air horn, no gap. Guess I need to pull it all off again and investigate.

 

No, they are all the same length. Slip a #2 wooden pencil between the air horn and choke plate, close the plate to bind against the pencil. You should have some adjustment left before the spring binds up. Give it a quarter turn for starters until you mount it on the intake and start the engine. The screw doesn't ride on the cam w/ choke open, per Mark and my pics.

Joe

 

Well your screw is definitely adjusted further in. I'll pull my carb off tomorrow for a better inspection and take photos.

Thanks for the help so far guys.

 

Different carb models, engines, cams.......just backed mine up a quarter after Mark's pics reminded me to do so.

To be more concise, fast idle screw should touch the cam w/ the gap @ the choke plate, turn in a quarter for starters.

Joe

 

OK popped the carb off. With the lever shut just enough for the plate to grip a #2 pencil, see photo, even with the screw in too far for the spring it does not touch the cam. Opened a little further, around 3/8", the screw is even further away. The answer seems to be a longer screw, or maybe bend the linkage rod, just don't know why..