84 FJ60 Aisin Carb Jet Question

[BlueOrwell]

Hey everyone! First time posting here so I hope I don't step afoul of anything. I've searched high and low thru the forums to find the answer to this question so posting has been my last resort. I am in the process of trying to get my 84 FJ60 up and running. This is my first *car* project (I've worked on a number of motorcycles) and my husband is helping, but for the most part I'm trying to get her going on my own. I've pulled the carburetor--which appears to be an original Aisin--and am getting ready to start the rebuild. When we pulled the jets, we noticed that there were long hairline cracks in what appears to be possibly an outer casing of both jets. They go approximately halfway up the stem. Now, I've never done a carb rebuild and used the original jets (always replaced), however, I am aware it is impossible to get the OEM ones (I've been looking for weeks, fwiw). Bc of this, both my husband and I are unsure if we can reuse these jets, or if this means I should get a whole new carb? Is it worth it to attempt a rebuild on this carb with these jets, or am I dead in the water?

 

[sark]

Looks like this thread may be helpful:

Possible Alternate Carb Main Jet Sources? Thread size and pitch info needed

forum.ih8mud.com

 

[CruiserTrash]

Hey everyone! First time posting here so I hope I don't step afoul of anything. I've searched high and low thru the forums to find the answer to this question so posting has been my last resort. I am in the process of trying to get my 84 FJ60 up and running. This is my first *car* project (I've worked on a number of motorcycles) and my husband is helping, but for the most part I'm trying to get her going on my own. I've pulled the carburetor--which appears to be an original Aisin--and am getting ready to start the rebuild. When we pulled the jets, we noticed that there were long hairline cracks in what appears to be possibly an outer casing of both jets. They go approximately halfway up the stem. Now, I've never done a carb rebuild and used the original jets (always replaced), however, I am aware it is impossible to get the OEM ones (I've been looking for weeks, fwiw). Bc of this, both my husband and I are unsure if we can reuse these jets, or if this means I should get a whole new carb? Is it worth it to attempt a rebuild on this carb with these jets, or am I dead in the water?

View attachment 3883509

Damn, never seen that before. I've heard the main jets in the bottom of the float bowl can be replaced with certain Mikuni motorcycle carb jets, but I'm not sure about the ones in your photo.

Does anyone know if the 40 Series carb rebuild kits come with these jets? There might be some other possibilities here.

 

[BlueOrwell]

Damn, never seen that before. I've heard the main jets in the bottom of the float bowl can be replaced with certain Mikuni motorcycle carb jets, but I'm not sure about the ones in your photo.

Does anyone know if the 40 Series carb rebuild kits come with these jets? There might be some other possibilities here.

The Keyster kit for the late 60s FJ40 (CARB60144) looks like it includes two equal lengths jets, but the info I can find in regards to the jet sizes seem to indicate a much smaller jet. I can't seem to find any kits or literature on the FJ60 addressing these jets and it's driving me bonkers lol

My understanding is that if I get a new carb (like from City Racer) I am forced to desmog as well?

 

[Pighead]

Does anyone know if the 40 Series carb rebuild kits come with these jets?

The Keyster kits for earlier carbs do indeed come with all kinds of jets that are never the size you want...

 

[Spike Strip]

The Keyster kit for the late 60s FJ40 (CARB60144) looks like it includes two equal lengths jets, but the info I can find in regards to the jet sizes seem to indicate a much smaller jet. I can't seem to find any kits or literature on the FJ60 addressing these jets and it's driving me bonkers lol

My understanding is that if I get a new carb (like from City Racer) I am forced to desmog as well?

There are Four jets in your carb: Two smaller jets in the float bowl, and the two slow jets you hold in your finger, above.

The kit you list above is for an earlier carb 1969 and is not correct for your application, although the slow jets will 'fit' (I think), they are not the same size as in your FJ60 Carb. The Keyster kit for 80-87 FJ60 is EK11-0383A LINK but does not include the slow jets. The 'size' of those jets corresponds to the size of the orifice at the small end of the shaft. The size will be stamped on the flat top. I don't remember off-hand what the USA sizes are. Edit: Slow primary 65, Secondary 90. Main Jets, stock, are 1.47 primary and 2.00 Secondary.

If you can de-smog, there are several options for you: You can buy a Toyota non-usa carb for $1000 (top quality), a Japanese aftermarket for about $350 or various Chinese clone carbs for around $100 available on ebay, amazon, MUD vendors, ets - quality is very hit 'n miss.

With a non-usa carb you will lose the High-Altitude-compensation system that adjusts the carb Air/Fuel mix if you happen to travel over 4000 ft elevation.

Honestly, these FJ60 Carbs are complicated and parts are scarce. I get that you want to tackle the challenge, and don't want to dissuade you from it, but if you want to keep the stock carb, the rebuild might be best left to one of the MUD Carb gurus on the board. I say this because you'll have to buy multiple carb kits and perhaps hunt down other parts and it all adds up quickly, whereas the rebuilder will have spare parts cores and the knowledge to properly tune the carb to run on modern gasoline.

There are a few good Youtube videos on rebuilding the Aisan carbs, should you still want to tackle it. Strongly suggested to watch them first, if you haven't already.

Good luck!

 

[BlueOrwell]

There are Four jets in your carb: Two smaller jets in the float bowl, and the two slow jets you hold in your finger, above.

The kit you list above is for an earlier carb 1969 and is not correct for your application, although the slow jets will 'fit' (I think), they are not the same size as in your FJ60 Carb. The Keyster kit for 80-87 FJ60 is EK11-0383A LINK but does not include the slow jets. The 'size' of those jets corresponds to the size of the orifice at the small end of the shaft. The size will be stamped on the flat top. I don't remember off-hand what the USA sizes are.

If you can de-smog, there are several options for you: You can buy a Toyota non-usa carb for $1000 (top quality), a Japanese aftermarket for about $350 or various Chinese clone carbs for around $100 available on ebay, amazon, MUD vendors, ets - quality is very hit 'n miss.

With a non-usa carb you will lose the High-Altitude-compensation system that adjusts the carb Air/Fuel mix if you happen to travel over 4000 ft elevation.

Honestly, these FJ60 Carbs are complicated and parts are scarce. I get that you want to tackle the challenge, and don't want to dissuade you from it, but if you want to keep the stock carb, the rebuild might be best left to one of the MUD Carb gurus on the board. I say this because you'll have to buy multiple carb kits and perhaps hunt down other parts and it all adds up quickly, whereas the rebuilder will have spare parts cores and the knowledge to properly tune the carb to run on modern gasoline.

There are a few good Youtube videos on rebuilding the Aisan carbs, should you still want to tackle it. Strongly suggested to watch them first, if you haven't already.

Good luck!

Definitely agree it's not the right carb kit! Just the only one I found that remotely resembled these slow jets. I can definitely desmog in my state, so it's feeling like that may be in the best interest of getting the truck running. Considering the number of other things that will require overhaul (like the gas tank, brakes, and whole new interior) it's starting to feel like I should box this carb up real nice and maybe store it away from a future restoration effort by a more experienced person for these. I have watched a few videos and done a few motorcycle carbs but this one has me doubting myself for sure.

 

[Spike Strip]

Maybe @NeverGiveUpYota who is also in that area can give you some guidance on sources - She walked this walk very well, already.

Build - Work In Progress aka: Badass

Female enthusiast off and on mud since '10 but first cruiser in hand was in 5/'08 thanks to a young guy I was dating who had a wealth of mechanical know how... that truck became my DD in 6/'10 after my little kermit the frog green kia rio threw a piston in her second engine (first went just...

forum.ih8mud.com

 

[mattressking]

Two items.

1. Yes I've seen them crack, morseo on 60 carbs than 40. The actual jets will fall out with compressed air so inspection of both slow jets is required.
2. You won't find slow jets from a 40 kit, incorrect sizing. You can only use napco 3F carb kits and you'll only find 65. 90 is available but I can't recall which kit offhand.

If you need slows, message me which, 65,90 or both.

 

[sogafarm]

I have a City-racer Fuji carb in my '75 FJ40. It comes with two sizes of jets for the primary and the secondary. The small jets come installed in both. Power seemed very weak but I'm running 17 vacuum so I installed the larger jets that came with it. The gas consumption was dramatically increased to the point I could visibly see the gauge going down fast. I used a 1/4 tank in my typical 5 mile loop fast! Power was excellent I must say but consumption is at an incredible rate compared to the the smaller jets. I've got the carb off the manifold now and I'm not sure but I think that the small washers might not have been installed with the jets and were free floating in the bowl with the larger jets.

Question for the carb guru's @mattressking: Would no washers behind the jets cause the crazy fuel consumption? I had planned on just reinstalling the smaller jets until I found the loose washers but now I'm wondering if that was the cause of the high consumption. If not I was wondering if I used a combo of the smaller jet in the primary and the larger in the secondary would that be smart or vise versa?
Thanks for any help.

 

[Spike Strip]

What are the sizes of the Jets you're using? Should be stamped on the flat of the Jet.

I don't see how the missing Jet washers could make much of a difference.

 

[mattressking]

If the jets aren’t sealing to the body, then it could be leaking fuel around the threads and not ‘metered’ via orifice. Since jets are soft, they can usually seal without but any issues or small damage to sealing surfaces will cause issues, best to install.

Aftermarket carbs do not stamp jet sizing on jets @Spike Strip so it requires gauges to measure orifice. Aftermarket carbs are ROW-jetted, so undersized out of the box for today’s fuel especially at sea level. Higher elevation can get away with it.

Regarding jetting and crazy fuel consumption I will have a few questions:

1. What is fuel consumption you’re seeing, is it corrected for larger tires/changes in gearing (if applicable).
2. When idling, look in carb throat and see if fuel is puddling/visible saturation, if not, no issue.
3. Fuel remains in the middle of sight glass at all times?

Aftermarket carbs are known to have a few issues that I’ve repetitively seen personally:

1. Venturi nozzle pickup tube will fall out of nozzle (poor casting). This requires disassembling carb.
2. Float can absorb water and become overweight, recommend testing float (only if fuel level does not stay in middle-ish of sight glass).

Start there and report back. If you’re at sea level, I’d recommend fixing vacuum leaks, 17 is fine, but 20-21 is better and achievable with proper maintenance.

 

[sogafarm]

What are the sizes of the Jets you're using? Should be stamped on the flat of the Jet.

I don't see how the missing Jet washers could make much of a difference.

No size listed on jets.

If the jets aren’t sealing to the body, then it could be leaking fuel around the threads and not ‘metered’ via orifice. Since jets are soft, they can usually seal without but any issues or small damage to sealing surfaces will cause issues, best to install.

Aftermarket carbs do not stamp jet sizing on jets @Spike Strip so it requires gauges to measure orifice. Aftermarket carbs are ROW-jetted, so undersized out of the box for today’s fuel especially at sea level. Higher elevation can get away with it.

Regarding jetting and crazy fuel consumption I will have a few questions:

1. What is fuel consumption you’re seeing, is it corrected for larger tires/changes in gearing (if applicable).
2. When idling, look in carb throat and see if fuel is puddling/visible saturation, if not, no issue.
3. Fuel remains in the middle of sight glass at all times?

Aftermarket carbs are known to have a few issues that I’ve repetitively seen personally:

1. Venturi nozzle pickup tube will fall out of nozzle (poor casting). This requires disassembling carb.
2. Float can absorb water and become overweight, recommend testing float (only if fuel level does not stay in middle-ish of sight glass).

Start there and report back. If you’re at sea level, I’d recommend fixing vacuum leaks, 17 is fine, but 20-21 is better and achievable with proper maintenance.

Same everything except changing of the jets. Vacuum has stayed consistent with both smaller and larger jets. 17 is the best i have been able to reach on both sizes and i have tried everything including new Remflex gasket over the past few years. Still has a slight exhaust leak when low rpms at load. All variables are the exact same with both size jets just fuel consumption went up huge and power went up noticeably. Looking at both jets, the larger is about twice the size of the smaller which would explain the power increase but the consumption was absolutely ridiculous with the two larger jets. I was thinking of putting the smaller in the primary and the larger in the secondary as a on demand boost and see how that works.

 

[RevISK]

This is interesting to me as I have the same carb and am thinking I'll swap jets at altitude for SAS in a few weeks. It's my understanding that the "spares" are high altitude jets?

 

[sogafarm]

This is interesting to me as I have the same carb and am thinking I'll swap jets at altitude for SAS in a few weeks. It's my understanding that the "spares" are high altitude jets?

The opposite, smaller high altitude jets come installed. The extra larger jets are behind the bolts so your set as is. Im trying to find a happy medium for fuel consumption and better efficiency by using smaller for most driving and the larger for a boost in the secondary when the pedal is pressed further.

 

[sogafarm]

Another option maybe to slightly drill out the small jet but I will try just using both sizes for a baseline and report back.

 

[chptuls]

Your power valve could be stuck open too to cause excessive fuel consumption.

 

[Spike Strip]

Stock Jet size for a '75 FJ40 would be 1.20/1.44 mm Primary (CA/FED), and 2.30 for the secondary, for both

With modern crap gas most recommend going slightly larger, but 2.30 is pretty big, already.

If you haven't seen it, SOR has a stock jet size chart:

Frequently Asked Questions About Your Land Cruiser - Specter Off-Road - https://www.sor.com/cat/005a#tab1

 

[mattressking]

Vacuum does not change when you change jetting, it richens or leans based on size. You can improve driveability and smoothness by masking vacuum leaks by richening mixture, but you're only causing more harm ultimately. Vacuum is the amount of 'suction' the engine is pulling during combustion process and is affected by a number of variables starting with valve clearances, gasket condition for intake manifold and any accessory directly connected or subject to engine vacuum (stemming from manifold).

If you want cheap/fast fixes, richen mixture, increase timing. Avoid pinging by limiting amount of base timing.

 

[sogafarm]

Just got them switched around. Of course I had to lose my little choke cable brass end cap but luckily had a spare. It’s 96 degrees and muggy and I’m soaked with sweat here in lovely South Georgia. I have to get some gas at the nearest station which is 10 miles away. I’ll report back later when it cools down to 90 around 7pm with a test drive. Runs good up the drive though. I used the smaller in the primary.
The secondary flap barely opens up almost at full throttle so not sure how much difference it will make.