As I said, mechanical advance only. It's not ideal, but it will work.
Distributor Vacuum
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As I said, mechanical advance only. It's not ideal, but it will work.
Your connection looks higher up, will check out soon. So spot it looks like you are running mechanical advance only?
I assumed my rig was Federal, how would I know if maybe it is a California model??
So having that vacuum retard line going into the lower front medial part of my carb could be causing my rig to run really poorly after warmed up at idle, stumbles, etc....????
spotcruiser
Geezer
Yep, I capped off the vac advance (retard) about 25 years ago. It runs OK this way.
A thermal reactor exhaust manifold would be a dead giveaway for a CA truck, if there. Perhaps the smog hose routing diagram on the hood. Or the overall layout of the smog gear/hoses. Original import/sale documents. Perhaps that's not the original dizzy. Just some possibilities.
I bought the truck new from Steven's Creek Toyota in Santa Clara/San Jose. It ran OK (not really ballsy, but OK) for the first 10 years or so. I took good care of it and kept it tuned up. I think as the smog equipment aged the engine performance began to suffer. I honestly never tried to purchase new smog components, but I think they have been in short supply and expensive from day 1. The CA smog components seemed to change from model year to model year, so there was a really small market for most items. One thing that eventually bothered me was that it would run good when cold and then backfire, shudder, and run less than ideally after the vac retard kicked-in at a certain temperature, so I disconnected that feature. Oddly enough, I have several later fully-electronic, vac advance distributors that I've never bothered to match up with a modified carb and install. I guess as you get older you don't so much mind record albums with pops and scratches. The songs just don't sound the same without all the background noise. The truck and I just kinda grew old and comfortable together.
A thermal reactor exhaust manifold would be a dead giveaway for a CA truck, if there. Perhaps the smog hose routing diagram on the hood. Or the overall layout of the smog gear/hoses. Original import/sale documents. Perhaps that's not the original dizzy. Just some possibilities.
I bought the truck new from Steven's Creek Toyota in Santa Clara/San Jose. It ran OK (not really ballsy, but OK) for the first 10 years or so. I took good care of it and kept it tuned up. I think as the smog equipment aged the engine performance began to suffer. I honestly never tried to purchase new smog components, but I think they have been in short supply and expensive from day 1. The CA smog components seemed to change from model year to model year, so there was a really small market for most items. One thing that eventually bothered me was that it would run good when cold and then backfire, shudder, and run less than ideally after the vac retard kicked-in at a certain temperature, so I disconnected that feature. Oddly enough, I have several later fully-electronic, vac advance distributors that I've never bothered to match up with a modified carb and install. I guess as you get older you don't so much mind record albums with pops and scratches. The songs just don't sound the same without all the background noise. The truck and I just kinda grew old and comfortable together.
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I just disconnected that vac retard hose, temporarily plugged end of hose going to carb and connection on vac can as well. Seems to idle smoother even when i turned it down 1/2 then back to down 1/4 turn. Cold up here today, 35 degrees and about 4 inches of snow on the ground up here at a mile high-who says it doesn't snow in Arizona! Otherwise I would be taking it for a test drive- roads will probably be dry tomorrow of Friday, sun melts stuff fast here-then I will really know how well she is running. Will update soon, now going to find some hose to run into my firewall(found hole-thx spot!). Spot do you run a filter at the end of that hose inside your firewall in the cabin area?
spotcruiser
Geezer
There's a special filter for it, but just about anything to keep dust and dirt out would probably be OK. This isn't a great photo, but it's what I could get without pulling stuff out. This is looking up at it, where it sits below one of the other control boxes in the passenger footwell (seat belt relay or cooling fan controller). As I mentioned before, it has a mounting bolt top and bottom.
Good article explaining vac/centrifugal advance. For v8 but same principles https://www.facebook.com/permalink.php?story_fbid=501928919949799&id=279002575575769
Howard-excellent article, really helped make vacuum more understandable. So, I need vacuum advance to improve further my engines running-especially at idle and upon deceleration. So the vacuum retard has nothing to do with proper running, just air pump emissions stuff right? Hopefully Jim will see my pics; seems as though I need a good stock distributor and my stock OEM carb rebuilt and tuned so I can benefit from the vacuum advance can hookup running into my carb. I also need his benefit of what needs to go on that line from the fuel seperator before it goes into the stock carb.
spotcruiser
Geezer
That's the whole evaporative emissions system. You probably don't have all of the parts, but it's still good to have the charcoal cannister connected to the fuel seperator and have it vented to the air cleaner, at the very least.
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Thanks spot, is the BVSV just part of the Water pump area?? Or is it a seperate piece? Also, where do the OVCV, and VCV mount??
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TLS, your original carb & distributor are 1978 fed spec parts. The current carb is 1980 non-US.
The dissy is vac advance & vac retard, but the vac advance fitting has been chopped off by some vandal
.
In this pic of another 1978 dissy, the vac advance fitting is visible, sticking out horizontally. The vac retard fitting is the capped one that points up.
As others said above, remove the hose that is connected to the vac retard fitting, and set base timing at 10-12*. It will run fine that way, and if you can get your hands on another electronic 78-87 vac advance dissy with good vac advance canister it will be even better.
The dissy is vac advance & vac retard, but the vac advance fitting has been chopped off by some vandal
.In this pic of another 1978 dissy, the vac advance fitting is visible, sticking out horizontally. The vac retard fitting is the capped one that points up.
As others said above, remove the hose that is connected to the vac retard fitting, and set base timing at 10-12*. It will run fine that way, and if you can get your hands on another electronic 78-87 vac advance dissy with good vac advance canister it will be even better.
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spotcruiser
Geezer
Wow. Jim's correct, it is a Federal distributor with the advance fitting cut off. 
I didn't look close enough to see the stub of a fitting. I can't imagine who would do something like that. That answers the question about Federal/CA, though.
If it was my distributor, I think I would look for a way to install a new pipe stub and see if the advancer still works.
The BVSV (bi-metal vacuum switching valve) screwed into a hole in the side of the thermo housing (so, you don't have two plastic fittings in the side of your thermo housing with hose barbs on them?). The OCV (outer control valve) was mounted on or adjacent to the charcoal cannister. The VCV (vacuum control valve) was on the driver's inner fender. All of this crap is inter-related (as shown by the table in the manual scan I provided) and functions by temp and vacuum level. If you don't have this stuff, you certainly don't want it unless you are required by regs to have full smog equipment. If you can find a charcoal cannister cheap, though, it's not a bad idea to have it connected. Some people complain about fuel fumes otherwise.
I didn't look close enough to see the stub of a fitting. I can't imagine who would do something like that. That answers the question about Federal/CA, though. If it was my distributor, I think I would look for a way to install a new pipe stub and see if the advancer still works.
TLS, your original carb & distributor are 1978 fed spec parts. The current carb is 1980 non-US. The dissy is vac advance & vac retard, but the vac advance fitting has been chopped off by some vandal
The BVSV (bi-metal vacuum switching valve) screwed into a hole in the side of the thermo housing (so, you don't have two plastic fittings in the side of your thermo housing with hose barbs on them?). The OCV (outer control valve) was mounted on or adjacent to the charcoal cannister. The VCV (vacuum control valve) was on the driver's inner fender. All of this crap is inter-related (as shown by the table in the manual scan I provided) and functions by temp and vacuum level. If you don't have this stuff, you certainly don't want it unless you are required by regs to have full smog equipment. If you can find a charcoal cannister cheap, though, it's not a bad idea to have it connected. Some people complain about fuel fumes otherwise.
Jim; I did remove that hose going to the retard fitting and temporarily blocked off the end of the hose and the fitting-where did you get that little black block off cap for the end of the can fitting? I found one at Autozone, will use that instead of my temporary cover. I started her up and she did seem to idle a bit smoother, not able to drive so I can see how it responds to load just yet as my top is off and we have 4 inches of snow on the ground up here!!! Would it be possible to fix my dizzy so I would have the vac advance fitting? What are your thoughts on installing charcoal cannister, outer vent control valve, VCV and BVSV? As you know all I currently have is the hose running from top of fuel seperator to carb area (red one I am holding in pic)? I do want to prevent fumes and if have you rebuild my stock/OEM carb I would want to connect it to carb.
Spot-will post up pics of what I think is my BVSV. Thanks guys.............
Spot-will post up pics of what I think is my BVSV. Thanks guys.............
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Spot is this upper connection my BVSV??? It may be missing one of its connectors......?
spotcruiser
Geezer
They are both BVSVs. Blue for evap and brown for spark control (vac retard or advance) I think. Yep, they're just thermo valves, so two hoses each.
So i need a "new" upper? I believe with my rig without air pump, I only need to connect the upper. I want to vent from the fuel seperator correctly. Thanks for the input
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TLS, the 78 canister & carb are interconnected in a couple ways. Most obviously is through the large bowl vent hose coming off the top of the carb, going across the firewall to the outer vent valve on top of the canister. Secondly, there is ported vac off the carb that passes through the brown BVSV to the VCV that purges the canister by connecting it to manifold vacuum.
It is advantageous to have all the canister & vent system in place. It carries no real reliability or performance penalty, while keeping more of your expensive fuel in the tank, and less of it stanking up the garage.
The missing parts needed to get back in operation:
canister w/ vent valve
1978 carburetor
canister purge pipe across firewall
canister vent pipe across firewall
VCV on driver's fender
misc hoses.
HTH
It is advantageous to have all the canister & vent system in place. It carries no real reliability or performance penalty, while keeping more of your expensive fuel in the tank, and less of it stanking up the garage.
The missing parts needed to get back in operation:
canister w/ vent valve
1978 carburetor
canister purge pipe across firewall
canister vent pipe across firewall
VCV on driver's fender
misc hoses.
HTH
Thanks Jim. Drove the rig today and it was a bit rough upon braking-have to eval booster. I still have the timing where murf set it at the shop 7 deg BTDC as per manual. So, you are suggesting making it 10-12 deg BTDC(below top dead center)? Is this advancing or retarding to compensate for the lack of vacuum advance from can to original carb?
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Yes, add some timing advance at idle to compensate for the loss of the vacuum advance.
