Quick carb question-slow idle cut off 2f

houstonfj40

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Looking at a rebuild on carb, want to run truck while that’s being done, and have a back up. Looking at the CityRacer non US OEM and other aftermarket. For. Desmogged application. The others don’t have the Slow Idle cut off. Is it internally or is this something I don’t need in desmogged application? Seem to not be present in non US OEM.

I have seen some other desmogged 60’s without this.

Item circled in picture. Thanks for the help.
 

houstonfj40

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Reason for rebuild is st idle there is a stumble and rpm drop every 10 seconds or so, like some extra fuel was dropped. And when AC idle up is on, sometimes at idle, drop in rpm and idle rich until throttle applied again. Figure it’s a carb issue, clean fuel filter. Might try red neck tune up.
 

FJ40Jim

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That's the secondary slow cut valve. It was added to USA 2F carbs to ensure that fuel is not dribbled out of the secondary idle port if the secondary throttle is not fully closed. Like many things, it is not needed, but is nice to have.
 

Rustic76

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Jump into the rebuild. I just did my first carb rebuild and my 60 was out of service for one day. Source a good rebuild kit, have a FSM handy, and pinhead’s YouTube videos. $80 total and it runs great.

Your secondary slow cut valve is also missing it’s rubber boot. I don’t think those come in the rebuild kit unfortunately though.
 

houstonfj40

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That's the secondary slow cut valve. It was added to USA 2F carbs to ensure that fuel is not dribbled out of the secondary idle port if the secondary throttle is not fully closed. Like many things, it is not needed, but is nice to have.
Thanks JimC. Running your pulley and may reach out for this rebuild. Coaching boys baseball right now, not enough time!

Marc
 

houstonfj40

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Jump into the rebuild. I just did my first carb rebuild and my 60 was out of service for one day. Source a good rebuild kit, have a FSM handy, and pinhead’s YouTube videos. $80 total and it runs great.

Your secondary slow cut valve is also missing it’s rubber boot. I don’t think those come in the rebuild kit unfortunately though.
Rustic76
Which kit did you use?
Marc
 

NeverGiveUpYota

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Someone, not sure who said the kit from O’Riellys is really good. Has more stuff in it than the one from Cruiser Outfitters. I saw a photo... it’s on my computer but I’m down for the count on my couch for now. And be sure to buy the accelerator pump from the dealership tho cuz the material on he stock one is leather as opposed to the aftermarket which is rubber. And soak it for a few hours prior to install in 90wt.
 

FJ40Jim

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The AP is always leather in a parts store kit.
The Keyster kit has the rubber AP plunger, but does include some jets that aren't in the store kits. Jets aren't normally needed.
 
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Someone, not sure who said the kit from O’Riellys is really good. Has more stuff in it than the one from Cruiser Outfitters. I saw a photo... it’s on my computer but I’m down for the count on my couch for now. And be sure to buy the accelerator pump from the dealership tho cuz the material on he stock one is leather as opposed to the aftermarket which is rubber. And soak it for a few hours prior to install in 90wt.
Maybe not “really good” - I can’t tell quality just by looking at these - but it had the - easy to lose - hotwheel tire looking gaskets that fit on top of the venturies. No other kit I’ve seen has had those. Otherwise, I liked the keyster kit from Kurt (maybe Jim sells it too) but mine didn’t have any jets and the plunger was rubber. I’m giving it a try in my rig right now, but I have a pleather one from the dealer I’ll pop in if necessary. Seems like the rubber seal on top of the plunger goes bad fairly quickly on the Hygrade kit - so good to get that from dealer too, it’s better quality. I’m hoping the keyster will last longer than my last one from the hygrade kit.
 
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I went to my local NAPA and got the one they offered. It was ok, it did not include the secondary diaphragm but they sell one separately if it’s needed.
They sell a brass float as well that is a nice upgrade to the spongy rubber original. The napa kit has a leather plunger and the venturi caps too. No, diaphragm though. Mine was okay so I didn't need it anyway.
 

FJ40Jim

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Be aware that Borg Warner & NAPA sell a brass float that is failure prone.

The OE black nitrophyl foam float is failure proof, so either re-use the stock one or get a new one from Toyota or sometimes found in aftermarket box.
 
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Be aware that Borg Warner & NAPA sell a brass float that is failure prone.

The OE black nitrophyl foam float is failure proof, so either re-use the stock one or get a new one from Toyota or sometimes found in aftermarket box.
Ah! Good to note. What exactly fails with the brass float? I was under the impression that the old float takes on fuel like a spong eventually and doesn't float properly.
 

FJ40Jim

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The brass floats have a number of problems, which is why they are no longer used. When the float is hot-soldered shut, it ends up with vacuum inside it when it cools. That vacuum makes the float very fragile, as a small dent will easily get turned into a big dent. The same vacuum inures that a any hint of a leak will definitely suck up liquid. The solder is not happy with modern gasahol blends and turns white & powdery, eventually failing & leaking.

The black nitrophyl is less dense than gas, so naturally floats. It is a closed cell foam, so even if a hole is drilled in it, it doesn't take on water beyond the hole.
 

houstonfj40

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Ok, so as I run vacuum checks around the truck. I am at 18 with BB dead on pin, and 19 with it advanced a little. But I am getting no vacuum to my dist advance or choke break (like a pound or two). Since this is where the ac idle up interacts with carb I am thinking my issue is down there. The vac to dist and choke is coming from my rear vac ports pictured. BTW, I think my vac advance on dist is no good also, not holding vac.
 

NeverGiveUpYota

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Vac pots are pretty much all bunk at this point of their age.
Choke breaker and openers can be rebuilt by a company in TX, Rebuilders Speciaties something or other, I can get you a contact number, just tag me if yes. Vac adv are not able to as of this time. I did send them one unmolested and one completely dissembled. I’ve not heard if they think they can rebuild them or not, figured it was worth a shot. I’ll text the guy and ask again if he’s had time to look them over.
 
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