85 vacuum advance

[85"720]

Does anyone know where I can buy a vacuum advance pot for my stock distributor. It's a 1985 720 2.4 rwd california model

[datzenmike]

Best would be from another truck. The part number is 22301-80W00 though I doubt the Nissan dealer may have one, maybe you can use this number to cross reference it to another supplier.

 

I doubt California emissions will check this so one from another distributor will work but it's advance curve will be different.

[Thomas Perkins]

Here is the part number.22301-80W20.I check the one Mike listed and it says it does not fit a 85.

[Thomas Perkins]

This part does not fit

1985 Nissan 720 Pickup

King Cab; 4 Cyl 2.4L; Deluxe; 5-Speed Manual Transmission FS5W71B; Long Bed Truck; Four-Wheel Drive; Federal

Check another vehicle.What is says about the part Mike listed.22301-80W00

 

Edited November 28, 2024 by Thomas Perkins

[datzenmike]

22301-80W20 is for the 4x4.

 

22301-80W00 is for '85- 2wd except HD. No mention of California emissions so good for Federal /California.

[Thomas Perkins]

My bad,I looked for them and can't find any.Post it on Facebook and you will get one.

Edited November 28, 2024 by Thomas Perkins

[85"720]

I've found those oem part numbers but can't find anything that cross references them. 

[datzenmike]

Any Z24 distributor vacuum advance canister will work. Emissions has no way to check this. Vacuum advance add ignition advance is response to throttle input. More throttle = less ported vacuum = less advance. Less throttle = more ported vacuum = more advance. None at idle and basically none the closer to WOT you get.

[85"720]

1 hour ago, datzenmike said:

Any Z24 distributor vacuum advance canister will work. Emissions has no way to check this. Vacuum advance add ignition advance is response to throttle input. More throttle = less ported vacuum = less advance. Less throttle = more ported vacuum = more advance. None at idle and basically none the closer to WOT you get.

I understand that. The thing is that the z24 distributor or any 720s in general are pretty rare in my area. It looks like I might have to buy a new distributor just to get a vacuum advance pot. 

 

[NC85ST]

Post a wanted ad on here. 

[Sephakrid]

I picked up a couple vacuum advances for a 1986 Nissan Stanza a while ago, but haven't tested them yet. They at least look the same!

[datzenmike]

There are 12 vacuum canisters for the '84 720 depending on multiple things like man or AT transmissions ... and 8 possible ones for the Stanza. The parts numbers do not match, they might fit and if they do it will work, but all are set a different advance under part throttle.

[Sephakrid]

So, I tested the Stanza vacuum advances. They are not identical (of course). However, I heard that Hitachi vacuum advances are adjustable so I went ahead and drilled out the sealant to see what was inside.

 

It seems like the outer screw adjusts the rate of advance, while the inner screw adjusts the total advance. Unfortunately, the first "step" seems to be non-adjustable. For instance, you'll always have 4° at 13.3 kPa regardless of how you adjust the screws. Either way, I plan to mess around and see how close I can get using the available adjustments.

 

 

 

 

Edited December 30, 2024 by Sephakrid
grammar

[datzenmike]

Bravo, I would have not bothered. But this is interesting to know.