3/69 - 9/69 carb and vacuum advance dist (1 Viewer)

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I recently picked up a 1969 FJ40 and I`m in the process of figuring out what it needs and getting it running a little better. I've had several 40's, 60's and pickups over the years but this one is the oldest! it's pretty solid and original but I'm finding some PO mods/issues I'm scratching my head over.

This engine has the weird 3/69-9/69 2 barrel carb on it. It also has an early vacuum advance distributor. I did a bunch of searches here on MUD about this carb since I was not familiar with it. (I've rebuilt a handful of other 40 and pickup carbs). It looks to have some of the vacuum lines capped and I don't see much for smog equipment, so I'm assuming it has had some of that removed.

From my searches, I thought that the 3/69-9/69 did not have ported vacuum, but this has a copper line from the base of the carb to the distributor. Every other carb of this vintage that I've seen has this port blocked. I couldn't find any diagrams in my manuals for this carb so I'm not sure if this location would be ported vacuum. My question for the carb gurus is, does this connection look correct for this carb/distributor combo? How would I go about determining if the distributor is functioning properly with it connected this way?

Here's a pic of the oddball carb. You can see the flare nut and hard line at the base:

i-J7wrrxN-L.jpg

i-v5T7Cqt-L.jpg



Here's the distributor:

i-P7b9DVL-M.jpg






Hoping Mark @65swb45 and JimC @FJ40Jim will chime in.

Any advice appreciated! Super excited to have another 40! :)
 
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I suppose i`ll go ahead and throw a timing light on it, see where its at, then pull the carb and get a better look to see if there is a passage where that copper line is attached. Hoping to just do a carb rebuild and tune it up. Really don't want to swap out the carb, aircleaner, linkage, or distributor if possible...
 
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In the thread below you can see the opening on the bottom of his 69 carb has a screw blocking it. He also has a vacuum retard distributor and the vacuum smog gear in place. Looks like I'm missing the choke breaker diaphragm and the "computer" (edit:vsv) on the fender?

Anyone have the fsm that has this carb in it? Mine has the earlier single barrel and later 2 barrel only.

 
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I recently picked up a 1969 FJ40 and I`m in the process of figuring out what it needs and getting it running a little better. I've had several 40's, 60's and pickups over the years but this one is the oldest! it's pretty solid and original but I'm finding some PO mods/issues I'm scratching my head over.

This engine has the weird 3/69-9/69 2 barrel carb on it. It also has an early vacuum advance distributor. I did a bunch of searches here on MUD about this carb since I was not familiar with it. (I've rebuilt a handful of other 40 and pickup carbs). It looks to have some of the vacuum lines capped and I don't see much for smog equipment, so I'm assuming it has had some of that removed.

From my searches, I thought that the 3/69-9/69 did not have ported vacuum, but this has a copper line from the base of the carb to the distributor. Every other carb of this vintage that I've seen has this port blocked. I couldn't find any diagrams in my manuals for this carb so I'm not sure if this location would be ported vacuum. My question for the carb gurus is, does this connection look correct for this carb/distributor combo? How would I go about determining if the distributor is functioning properly with it connected this way?

Here's a pic of the oddball carb. You can see the flare nut and hard line at the base:

i-J7wrrxN-L.jpg

i-v5T7Cqt-L.jpg



Here's the distributor:

i-P7b9DVL-M.jpg






Hoping Mark @65swb45 and JimC @FJ40Jim will chime in.

Any advice appreciated! Super excited to have another 40! :)
Connection from the port on from the base of the carb to the dizzy is correct. This creates the vacuum advance at increased speeds. To set timing, remove line from the dizzy and cap it.

I do not believe ‘69 had much smog equipment. You are correct that there is a small “computer” on the fender, but most people remove it as I doubt it still functions correctly.
 
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Thanks for posting those diagrams, I don't have those and I'm definitely missing the vsv.

For the vacuum, I believe it needs to be above the primary throttle plate for vacuum advance. Which would be the ported vacuum I was referring too. Bottom of carb or off the manifold would be manifold vacuum, which isn't correct for the vacuum advance distributor i have. This carb i`m clueless about though and my guess is that the poor performance is due to the vacuum advance distributor being fed manifold vacuum.
 
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Thanks for posting those diagrams, I don't have those and I'm definitely missing the vsv.

For the vacuum, I believe it needs to be above the primary throttle plate for vacuum advance. Which would be the ported vacuum I was referring too. Bottom of carb or off the manifold would be manifold vacuum, which isn't correct for the vacuum advance distributor i have. This carb i`m clueless about though and my guess is that the poor performance is due to the vacuum advance distributor being fed manifold vacuum.
I think that is the correct location. Here is an stock advance port location on a ‘70 Carb for comparison (at the end of orange high lighter).

***********
Edited 2/2/21 - Please note that the port found on the '70s carb pictured below is not a correct port for vacuum advance. See post #14 below where FJ40Jim discusses the proper placement for a vacuum advance port.
***********
 
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Found another thread about this carb. Good info, so thought I would link it here.


Still trying to determine if the hardline to my distributor is ported vacuum or not. Going to pull it off today.
 
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So I pulled the carb off and the opening feeding the distributor is below the throttle plate, so its manifold vacuum, not ported vacuum. That could explain part of the poor running issue.

Guess I`ll pull the 3/69-9/69 carb and start looking for a late 69 with ported vacuum and the appropriate intake. If anyone has the parts, let me know!
 

FJ40Jim

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The 1971 carb picture is not pointing to a ported vac fitting.

Here's a similar 1975 non-US carb showing the ported vac fitting. Note that it is beside the idle plug and slightly above centerline of plug.
IMG_20201218_174922852_HDR.jpg


The OPs carb has been modded by replacing the idle plug with a vac fitting from a different carb, but the added vac fitting is seeing the entirety of the idle circuit, so is always at some level of vacuum.

It is very difficult to drill in a ported vac fitting on the 69 2bbl. It does not have the obvious boss cast on the carb to hold a fitting. Easiest to just use the vac retard dissy with all of it's mechanical advance.
 
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The 1971 carb picture is not pointing to a ported vac fitting.


The OPs carb has been modded by replacing the idle plug with a vac fitting from a different carb, but the added vac fitting is seeing the entirety of the idle circuit, so is always at some level of vacuum.

It is very difficult to drill in a ported vac fitting on the 69 2bbl. It does not have the obvious boss cast on the carb to hold a fitting. Easiest to just use the vac retard dissy with all of it's mechanical advance.

Thanks for clarifying that Jim. I`m going to remove the existing carb and replace it with a good late 69-71 carb with ported vacuum like you pictured.

The current carb has a hand throttle. How does it attach on the later version carb?
 

FJ40Jim

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Thanks for clarifying that Jim. I`m going to remove the existing carb and replace it with a good late 69-71 carb with ported vacuum like you pictured.

The current carb has a hand throttle. How does it attach on the later version carb?
Check with @dlzadl , he just did the 69 to 71 swap and it requires more than a carb. He might have a parts list.

The hand throttle connects to the top of the pedal on 70-newer.
 
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Check with @dlzadl , he just did the 69 to 71 swap and it requires more than a carb. He might have a parts list.

The hand throttle connects to the top of the pedal on 70-newer.
Darn, was hoping it would be simple! But such is life. ;)

That`s the one feature of the 3/69-9/69 thats actually quite nice is how cleanly it handles the throttle, choke and hand throttle cables. I might have to get creative.

Jim, I had another question about the ported vacuum: can a ported base/flange from a later carb (77) be used under an older carb body? They look similar.
 
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FJ40Jim

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I had another question about the ported vacuum: can a ported base/flange from a later carb (77) be used under an older carb body? They look similar.
The ported vac fitting can be added to any of the 1970-newer 2bbl, if missing.

The throttle bodies can be swapped between some carbs, but not all. Depends on mech or vac secondary, throttle linkage, etc.
 

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