Non-USA FJ45 emissions help (1 Viewer)

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Jul 24, 2005
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MA
I've got a 1977 Central American FJ45 that seems to be missing what little emissions equipment it should have. I'm looking for a source for a non-USA emissions manual or some guidance from someone with a fully put together non-US truck. Alternatively, is there an earlier year of US truck whose emissions manual would be close enough to piece something together? Based on the page counts on SOR, I'm thinking '71 or earlier (the US '77 manual if 430 pages and even the 124 page '72 manual seems like way too many pages for what I should have going on).

Here are the specific issues I'm trying to solve:

1. The vacuum advance on the distributor is not connected. The truck idles fine, but smokes at higher RPMs which I suspect is due to the lack of the advance leading to incomplete combustion. I can't figure out what to plug it in to. My carburetor has a 9 I 2 stamp on the front, so I think it is '79 that was a replacement at some point, but it is clearly a non-USA carb. It has one vacuum port near the idle mixture screw which the throttle positioner is plugged in to. Can I splice in a tee and connect the distributor to this port? It looks like US carbs have the TP hooked up to manifold vacuum, correct? The only vacuum line on my manifold is the brake booster. There are a few plugged ports on the carb that look like they were done in the factory, but I can't be sure. There are also some plugs in the manifold that look removable, but have clearly been in there a while.

2. The gas tank has no vent lines, vapor separator, charcoal canister or anything. As a result, the cab reeks of gas, especially on hot days. I've removed the tank before and didn't find any pinholes. The tank has the hard vents that look the same as US models, so I was going to hook them up to a vapor separator, but what beyond that? Did a non-USA truck of this vintage have a charcoal canister? If so, does anyone have an idea of how it was plumbed? I've been comparing what I have to the desmog diagrams, but I don't have a VSV. I can't tell if there was ever supposed to be a VSV, or if it was pulled out whenever the tank vents were removed (I am also not sure what would have controlled the VSV). At the very least, I will run the vent lines out of the cab, but I'd prefer to not have any gas smell, especially since I don't drive the truck that often. On the off chance that a '77 non-US truck didn't have a charcoal canister, I'm thinking of adding per this thread Hooking up Charcoal canister and fuel seperater and either not running a VSV and just plugging it into the manifold, or adding a "manual VSV" and just wiring it to a button or switch in the cab to vent. Does anyone know how long the VSV normally switches for? Also, per the US manuals, is the VSV supposed to be switching the vacuum on the TP? I could see the idea being that when the fuel from the charcoal canister was being burned, the TP would be "off" and when the charcoal canister was "off," the TP would be "on" to keep the amount of gas going to the engine more or less the same, but I'm just guessing at that.

While I can't exactly tell what is going on vs. what should be going on, I suspect a guy named Jorge may know has he seems to have signed his work by etching his name on the valve cover. I haven't been able to track him down unfortunately ¯\_(ツ)_/¯
 

Bear

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So your local jurisdiction/state requires some degree of emissions compliance? Are they asking for you to have the complete setup--Federal, or have they adopted the more rigid California-spec? What year registration has been given to your truck by your state--1977, 1978, 1979?

If needing strict compliance I would assume the 1979 carb could be a problem for a non-1979 truck. Items like a catalytic converter, the "thermonuclear" exhaust component, the rudimentary "computer" to control emissions, venting gas cap, etc. come to mind. Does your state do a "physical eyes-only inspection" or are they using a "sniffer test" at the tailpipe at temperature and with a full dynomometer setup at different RPMs?

Perhaps someone from your state will chime in here with their understanding of the specific requirements you need to meet.

Good luck to you. Oh, and say "Hi" to Jorge. Must be a whale of a mechanic to sign his own work so proudly.
 

whitey45

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Never heard of someone wanting to ad emissions to a truck that came with none to begin with. Keep it simple, unless you need to pass emissions.
 
Joined
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None of what I am trying to add is US-specific emissions equipment, and I'm not worried about having to add US-spec emissions equipment to an imported truck. I'm 99.9% sure that the vacuum advance should be hooked to something, and I am 80% sure that the gas tank on anything from 1977 was supposed to have an evap system. I just don't know how it was hooked up and while it is a simple enough system to figure out on my own, I'd rather do it correctly if someone knows the answer or can point me to the correct manual.

Emissions testing in MA is just visual for non-OBDII vehicles, but I am a little worried about the little bit of grayish smoke it makes above idle. I'm not 100% sure that is due to the lack of the vacuum advance being hooked up, but I can't see a good reason to leave a vacuum advance unconnected in any case. I can tell from the 1977 Toyota chassis manual that it is in fact a vacuum advance throttle (and that US ones from that year were vacuum retard), but the chassis manual doesn't show where the vacuum line is supposed to connect on the other end.

The fuel tank without proper vents is a bit of a safety issue, but mostly I just don't like smelling like gas. The parts to rig up a charcoal system are cheap and it doesn't impact performance at all, but I'd rather try to put back what was stock rather than free-styling something.
 
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None of what I am trying to add is US-specific emissions equipment, and I'm not worried about having to add US-spec emissions equipment to an imported truck. I'm 99.9% sure that the vacuum advance should be hooked to something, and I am 80% sure that the gas tank on anything from 1977 was supposed to have an evap system. I just don't know how it was hooked up and while it is a simple enough system to figure out on my own, I'd rather do it correctly if someone knows the answer or can point me to the correct manual.

Emissions testing in MA is just visual for non-OBDII vehicles, but I am a little worried about the little bit of grayish smoke it makes above idle. I'm not 100% sure that is due to the lack of the vacuum advance being hooked up, but I can't see a good reason to leave a vacuum advance unconnected in any case. I can tell from the 1977 Toyota chassis manual that it is in fact a vacuum advance throttle (and that US ones from that year were vacuum retard), but the chassis manual doesn't show where the vacuum line is supposed to connect on the other end.

The fuel tank without proper vents is a bit of a safety issue, but mostly I just don't like smelling like gas. The parts to rig up a charcoal system are cheap and it doesn't impact performance at all, but I'd rather try to put back what was stock rather than free-styling something.

If MA does not care, why do you ?
 

3_puppies

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have you tested the advancer unit to make sure it actually works? there are quite a few trucks running around who think there advance is working when it is not moving. the lack of advance should not be causing smoking, there are other issues
IIRCC it should be hooked up to ported vacumn off the carb

are you using a vented gas cap? have you run without the gas cap? does it still smell inside?
 
Joined
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I haven't tested the advancer yet, but it's on the to do list once I buy some more vacuum hose. Like most issues on this truck, I'm sure the smoke is a combination of many small problems which is why I am trying to go through and fix the things that are clearly wrong. When I bought it it only ran by pouring gas down the carb so I'm making progress at least!

I have a keyed gas gap with a cracked seal. There seems to be an assumption that keyed gas caps vent through the key hole, but I don't see how mine would do that as the keyway doesn't go all the way through the cap. Aside from the state of the seal, I don't think it vents, but I've left if off entirely to test and while it does cut down on the smell inside the cab, it then smells like gas on the outside.

From looking at Federal-spec emissions diagram, I think the vacuum advance should be hooked to the ported vacuum and the TP should be hooked up to the manifold, but I've also seen pictures on mud with TPs hooked up to carb ports that I don't have. I can verify from Toyota manuals that in some applications the TP should be hooked to the manifold (via a VSV that I don't have), but I haven't seen any Toyota manual that shows the TP-to-carb port is actually correct, although I haven't seen a lot of early emissions diagrams (or any non-USA diagrams) floating around online since most people are having trouble the complicated late 70s US stuff.
 
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Long post, so here's my question: Does anyone know where to hookup the throttle positioner/choke breaker on a truck that doesn't have a VSV/EVAP system?

I adjusted the timing and checked the vacuum advance -- it works. I hooked it up to the ported vacuum which makes sense. If it was on manifold vacuum, it would be advanced all of the time. I disconnected the throttle positioner vacuum line for now as I think it was hooked up to the wrong place (to where the vacuum advance is now hooked).

Unfortunately the 2F engine manual doesn't show where the TP connects (I assume because that varies depending on the emissions setup). My PCV is hooked to a very non-stock-looking fitting, and there are two plugged vacuum ports above it (see picture). I can't tell if those are factory plugged. From searching Toyota patents, it seems like the TP should have a vacuum source just downstream of the throttle plate. which would suggest that I could somehow connect it to the same source as the PCV if I found a different fitting. There is a curled up vacuum nipple on the PCV fitting, so perhaps it used to be connected there? This seems to be the correct location on early 70s US carbs per the carb identified pics on SOR although I don't see where the PCV hose was supposed to go on those.

What has me confused on this is Fed-smog trucks seem to have the TP connected to the manifold via the VSV along with the EVAP system. I've seen some examples of desmogged trucks with the TP hooked directly to manifold, but these were all poorly desmogged trucks where someone had just ripped out all the vacuum lines they saw. The desmog guides on mud show that the EVAP and VSV should stay intact. I still can't tell if someone desmogged this thing (from its already minimal non-US emissions equipment), or if it never had and EVAP/VSV in the first space.

Moving on to the EVAP side, it is clear that my tank should have a vapor separator, so I ordered one along with the valve. I didn't get exactly what the vapor separator did (other than somehow separating vapors) so I turned to the patents again. It seems it functions like an expansion tank in a more compact package with the valve allowing some negative and positive pressure to build before it opens. I ordered an FJ60 one as it was 1/3 the price, although from the patents it seems like if would also be simple to make a DIY separator with some larger diameter fuel hose too. That should cut down on a lot of the gas smell. If I ever figure out the vacuum side of things, I can decide if I want to hook the vapor separator up to a charcoal canister, or just put a little air filter on it and call it a day.


20200728_093919.jpg
 
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Update just to close things out for posterity's sake. Inspection passed. Mostly they cared about lights working and the corrections to the carb stopped the smoke under load, so no problem on the visual smog check.

I hooked the vacuum advance to the correct port, unhooked the throttle positioner and reconnected it to the PCV line with a tee fitting. Not the cleanest looking setup, but consistent with the overall state of things with the truck. I'm assuming the vacuum advance had the bigger impact on the elimination of the light smoke under load.

I think I have also figured out why the throttle positioner/choke breaker has two names. Originally, I thought it was just interchangeable, but after messing around with the vacuum and reading more patents, I *think* it is doing two totally separate things: In its choke breaker function, it is cracking open the choke on starting once manifold pressure builds a bit. While I haven't noticed any real difference in starting since I hooked it up to manifold vacuum from ported vacuum, I imagine this is more important in the cold.

When rebuilding the carb years ago, I paid attention to put it together correctly, but I didn't pay that much attention to what all the linkages did. I studied it a little more now, and I think the throttle positioner is doing what the above referenced patent suggested: it opens the throttle a bit when manifold pressure increases. If you are WOT, manifold pressure is low. If you let off the gas from WOT, it will crack open the throttle a bit which apparently helps prevent misfires from the manifold pressure spiking. I didn't drive it hard much before fixing this so I didn't notice a difference, but things didn't get any worse!

In terms of the fuel tank, I bought a used check valve and a vapor separator from an FJ60 as it was about 1/3 the price of the correct FJ40 one. I also bought the cheapest basic but decent-size charcoal canister I could find ($50). There is a very good chance that my gas tank isn't original, so it is possible that the correct tank is non-vented and just has a venting gas cap, but I still didn't like how much it stunk of gas, let alone the environmental side of things. With the small cab and the gas tank in it, it really seemed to puff out a lot of vapor in the heat of the day.

I ended up making a hybrid between the US-spec EVAP system, and what older boats have. I have the vapor separator and check valve hooked up as normal, and then hooked the check valve up to the charcoal canister. The canister, like in an older boat, isn't hooked to anything. From what I can find online, the charcoal canister adsorbs vapors that make it past the check valve, and then desorbs them as you pull in air through the check valve when the tank runs low or as the tank cools and pulls back in fresh air. I assume the system works better with the purge function when hooked up to the intake, but that was a lot more plumbing and there was nothing to control the valves, so I am very happy with this setup.

It is very possible that I did some of this wrong as I never could find a Toyota manual for non-USA emissions, but it makes sense to me and has reduced the problems I was having so I figure I'd pass along my experience.
 

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