79' 2f Aisan Carb -Jets question... (1 Viewer)

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i'm into my carb and had a look at the jet sizes... or trying to figure that out.

first i noticed my Brass Jet 150 is in the Secondary and the Silver/Chrome 220 is in the Primary.

the Primary should have the smaller of the two jets?
 

Dizzy

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In my '75, USA-spec, I found a 144 primary, and a 230 as the secondary. The primary is located on the valve cover side, on an Aisan. My suspicion is that the jets were swapped.

I just got a non-USA carb. It came with spare jets in the jet access plugs.
 
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thanks for that. I think these jets will be fine once in their correct place. Yes primary is closest to the accel pump, valve cover side with the triple venturi.
why are the jets different materials?
 

mattressking

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In my '75, USA-spec, I found a 144 primary, and a 230 as the secondary. The primary is located on the valve cover side, on an Aisan. My suspicion is that the jets were swapped.

I just got a non-USA carb. It came with spare jets in the jet access plugs.
What are the sizes in the carb/spares? I'm curious what they are providing. I assume 138/200?
 

thebigredrocker

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A 78 is a very different vac secondary carb with very different jet sizes.

Jim has mention jet sizes. Can't find those posts.



I just pulled my 12/78 carb apart a little bit last week and I'm pretty sure these are the stock jet sizes for that build date:

Primary main: 1.36mm
Secondary main: 1.71mm
Primary slow: 0.75mm
Secondary slow: 0.80mm

I haven't pulled the power jet yet, but I think the primary main along with the power jet will be your two primary sources to look at for whether you're running rich or lean. Obviously the secondaries have a part in it as well, but I would check those first. Sounds like bumping up to the 1.44mm on your primary main was a good idea.

I don't know much about octane and how that affects engine performance, but I have come to the understanding that you want to use higher octane for higher compression engines, which a 2F is not. I have read here on MUD some other things about octane, you might want to research and make sure you're running the correct octane fuel. Maybe using an 86 or 88 octane will help a bit? My '77 doesn't seem to care much about 10% ethanol gas, which is standard here. That may or may not have an effect on what you're experiencing.
 

FJ40Jim

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i'm into my carb and had a look at the jet sizes... or trying to figure that out.

first i noticed my Brass Jet 150 is in the Secondary and the Silver/Chrome 220 is in the Primary.

the Primary should have the smaller of the two jets?
Those jet sizes are for a non-US 2F carb.
If it is a non-US, then yes, the 150 is Pri Main.

If it is 1/79 - 7/80 US spec, the the larger jet (165) is Pri, smaller jet (144) secondary.
why are the jets different materials?
They are both brass, but on some applications the secondary jet is nickel plated. The plating is usually gone after 20 years of gasoline immersion. Maybe this is a newer non-smog replacement carb.
What are the sizes in the carb/spares? I'm curious what they are providing. I assume 138/200?
Depends on market. 150/220 is pretty common.
 

thebigredrocker

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Thanks FJ40Jim.

Here's FJ40Jim's Land Cruiser business for folks who want a Toyota expert to dial in their rigs.

57E8984D-2C54-479D-9C83-35C49DE2FC65.png
 

Dizzy

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My question is more pointed to the new OEM carb's that are still available and what they are entering in. Supposed I'd need to see which pn's folks are buying to start pinpointing specifics.
I got it from City Racer, just the other day. I needed the spacer, and I wanted a few extra threads on the carb stud so it stood like my smogerator did, so I made one serviceable one, and two sloppy ones that I rejected, with a long M6x1 and a Hanson die - it isn't easy getting a die perpendicular to the axis on an un-threaded rod.

Please support Land Cruiser specific businesses. The part number for the City Racer carb is 21100-61012. I just came back from Toyota, and the new face at the parts desk told me, "we don't have anything before 1985." But, I just got oil filters a few weeks ago. All I wanted was to sneak an extra disk brake wheel in the house without setting off the UPS-alarm for my parts hoard.

The non-USA carb had what looked like a 138 primary, and 134 primary in storage. I changed nothing, and I didn't peak into the secondary. I just installed it and have been really surprised by the performance enhancement. I was running a '75 Federal Spec pieced together from two engines, that probably had too much gas and water dry out in them.

I wonder what carb Toyota used for the forklift models?
 
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65swb45

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Follow the bore. Unlike any other years, The 79-80 has a bigger bore/ oriface on the primary side. So it gets the bigger jet. But 2.20 is still way too big for a primary. Typical American MIBS mentality.
 
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well now i need to look at this again.... i did read the same thing somewhere as well. only jets i got are the 1.50 and 2.20

72CA7408-8A9E-4098-81C7-74C322931EAF.jpeg


55163405-21DE-4FE5-A50E-77C6C43CCA8E.jpeg
 

65swb45

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Yet another instance where a picture is worth a thousand words.

A 61025 US spec carb would not only have the orifices swapped, there would not be a secondary slow jet. You obviously DO have a secondary slo jet. So we are not dealing with a 79/80 US spec carb. 1.50/2.20 IS a standard world-spec jetting in that time frame. And it appears your orifices are standard.

So the likely conclusion is that you have a world-spec carb.

As a side note, the 1980 dizzy has a 61101 suffix code. So there’s that as well.
 
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More wisdom from the elder statesman that will be getting bookmarked for later reference. Thank you Mark, your services are appreciated. :clap: These particular details are especially useful today with the influx of more world-spec carbs into the US as possible replacement options. :cheers:
 

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