FJ40 11/75 -8/76 Federal Aisin Carb Rebuild Candidate?

[Ackcruisers]

I acquired an Aisin carb which I believe is 11/75 - 8/76 federal. Before I spend the time to rebuild it, can someone provide confirmation on the Carburetor year and part #. I think it’s a 21100-61022 2/76-8/76. I need to put together parts list.

 

[Grayscale]

How about the stamps on the air horn? That will tell you about the date. Visually, your identification appears correct, to me.

That carb looks really rough. I'd do a complete tear-down before ordering parts. The throttle shaft is frozen? The throttle position switch appears absent, is it necessary?

 

[Ackcruisers]

Thanks for the air horn identification reminder. I agree, the carb looks rough…I wonder if it would even qualify as a “core” credit. The throttle valve does move freely even with the corrosion. The air horn stamp is 6 B 11…so it’s a 2/11/76 carb manufacture date.

 

[Grayscale]

I can send you either the cast-iron throttle casting, from a '75, or the equivalent alloy throttle base from a never-used chinacarb - it bolts on to the early 2F Aisan EGR insulator spacer but not rusted internally.

I said throttle position switch, earlier. I meant thermo switch at carb. Are you trying to re-smog?

 

[Ackcruisers]

Thank you for the offer...I need to take everything apart as you suggested first and assess.

I’m not resmogging. I want to replace my 21100-60012 H3662 chinacarb with OEM Aisan carb.I’m educating myself along the way.

Is it possible to delete the insulator 21165-61020 as shown and replace with an insulator parts from a knock off?

Based on your message, it sounds like the throttle body of an aftermarket will mate up?

The thermal switch is the solenoid throttle valve 21062-61020?

 

[Grayscale]

Well, from what I gather, my non-USA Aisan (CityRacerllc) is a shorter carburetor than the one that belongs under a USA '75 air cleaner assembly on its native USA-market 2F. Also, I was able to sandwich together the clone of the non-USA Aisan, chinacarb with the EGR (from a '75 USA carb) inlet spacer/insulator (equivalent to circled part above). The result is a taller carb than the chinacarb / non-USA Aisan, which will fit without aftermarket spacer under the '75 USA air cleaner assembly; I'm not sure that having that unused EGR inlet is better than using the CityRacer carb spacer, but, it is a different way of doing the same thing. Some linkage needs to be borrowed over as well, but the secondary diaphragms seem the same length - I remain perplexed. I'll grab a photo when I get a chance.

On the very first pic, in the first post. Right under the primary jet access plug (one on left), there is a threaded hole in the iron casting, that once had the thermo sensor switch - a brass part with a spade connection in back.

I have an extra early 2F air cleaner assembly collecting dust - USA-spec.

 

[Ackcruisers]

Thanks @Grayscale…I will be better off buying a new Non USA Aisan 21100-61012 that City Racer one had in stock. They’re still available overseas. If anyone who sees this post is in need of a 2/76 federal core, let me know. I’ll take the proceeds to help me justify the purchase of the OEM Non USA carb from Amayama.


I’m posting a photo courtesy of Spector Off Road of the thermo sensor that screws into the base casting. It appears that was only required for California spec vehicles. It is required to open up the valve on the EGR circuit.

 

[1MOA]

She's a beaut Clark!
I would tear that totally down to see what it's condition is before rebuilding.

 

[Grayscale]

I would like to report that using the choke-breaker diaphragm, as on the original USA smog carbs, is a really nice aspect of my original carb that is missing from the Aisan non-USA for 2F (CityRacerllc), china2Fcarb, and others. When the engine gets vacuum, it prevents the choke from being too closed, and so it becomes a friendly ride for anyone without the perfect choke "touch." They are kinda vacuum leaks by now, but if you can get one to attach to the choke butterfly (which if I recall correctly requires me to remove the choke butterfly peeded screws, so I'm not brave to have actually done it yet), it would be golden, paired with a fresh carb, as far as really cold weather ease of driving.

If I understand this correctly, your air cleaner assembly fits perfect with the china2Fcarb, so you wouldn't be able to squeeze a USA carb under it?

As far as rebuild kits go, there is a big difference in the gasket between the bowl and air horn, aside from that, I wonder how much is identical?

Anecdotally, I was able to improve my mpg from where I was using the '75 Federal rusty carb that I frankensteined and rebuilt. It looked like Toyota even provided a leaner jets in the extra jet holders in the bowl. for the new 2F carb I bet those would be fine for summer, and I believe they were intended for my higer altitude(?)

 

[Grayscale]

I was incorrect, the choke breaker from a junkyard '75 can be fitted to a chinacarb. That, and as many old parts as I could borrow. I wish I could open the bowl, but, they used gasket sealer on the gasket. I can look at my amazon if anyone needs to know the brand - there are so many and they are all the same basic carb?

New plus old.

Fuel delivery with the non-USA carbs means no fuel return line, unless you drill and tap the castings hole for threads.

I (or anyone else) really should try the hybrid build out... My non-USA Racer Aisan didn't get the choke breker, but, I could probably do it too. Even the float bowl window is the old style. Maybe when wrenches aren't so cold to touch, I'll instal? One thing about the non-USA carbs, and its clones, is that they need a barrel cable stop for the choke cable.

@Ackcruisers Does your chinacarb have a sealant on the bowl gasket? I always remove the air horn so I can get as much as fuel as I can out with compressed air before it goes into storage. I suppose that carb dip would remove the varnish anyway, but, I don't have a can of the stuff for storage reasons.

 

[Ackcruisers]

I likely can squeeze the USA carb under my air cleaner assembly.…

General Markets / NON USA carbs OEM # 21100-61010 were made with choke breakers. My 76 General Markets 2F FJ40 truck originally was equipped with the the 61010. Below is an image of the 21100-61010. Here are more.

The absence of the fuel return on the 21100-61012 NON USA carb would require the use of a later model fuel pump. That’s what I am running now. Made that upgrade with my fuel system overhaul last summer. For those looking at this thread in future, the details are in my post here.

Based on your images, the EGR insulator on the NON USA carb therefor we can use the non USA insulator on the USA carb. The insulator for NON USA carbs can still be purchased overseas. The part numbers are 21593-61010 for 1/75- 4/79 and then 21165-61022 4/79 - 7/80.

 

[Ackcruisers]

Finally took it apart. Looks to be in very good shape for a rebuild.

 

[Ackcruisers]

 

[cims1970fj40]

@Ackcruisers Im currently working on my vacuum lines and have a 75 carb. My question is did you run your vacuum line like circled in the picture as number 1? Also did you cap off number 2?

 

[cims1970fj40]

Forgot the picture

 

[Ackcruisers]

@cims1970fj40 i have not installed the carb yet. I’m running a small cap non USA vacuum advance distributor and was planning on capping the large vacuum intake and connecting the vacuum advance to the base of the carb.

 

[mattressking]

@cims1970fj40 i have not installed the carb yet. I’m running a small cap non USA vacuum advance distributor and was planning on capping the large vacuum intake and connecting the vacuum advance to the base of the carb.

You should hunt for a 79/80 insulator. It’s the same thickness but doesn’t have the egr inlet.

The rest will connect as usual see below.

 

[Pighead]

was planning on capping the large vacuum intake and connecting the vacuum advance to the base of the carb

I just cut that tube off and filled the hole with JB weld

 

[cims1970fj40]

You should hunt for a 79/80 insulator. It’s the same thickness but doesn’t have the egr inlet.

The rest will connect as usual see below.

View attachment 3712517

Actually that’s probably what I have. Doesn’t have that port in the insulator