FJ40Jim on this vacuum can, where do the connections go to?
Distributor Vacuum
- Thread starter SleeZee
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I agree with your assessment. My new equipment comes down on the 31st. I plan to check the timing, engine cold, and see if I can catch a picture of the timing mark, if it appears in the window on the bell housing even. Then I will check, engine still cold, with the vacuum hose plugged into the distributor to see what amount of advance occurs. Then I plan to install new points, rotor and cap, set the dwell per specifications. I will, hopefully, replace my NGK plugs with Denso and run the engine up to temperature and then check/adjust timing and then once again check with the vacuum advance hose attached. Hopefully then I can respond with good information. It is my intent to fully understand the information provided by the GM/Chrysler engineer I posted in #14. At this time the information seems to be "proven" but I agree with you that without knowing what the timing is at this time the experience is valuable only to me.
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What vac can? In what truck? Gimme some context, work with me people!
Jim 1978 FJ40 Federal Model. You mentioned 2 connections off the vac can on the side of the distributor, where does each one go? You mentioned one advances and one retards the timing. Bummer is my '78 has a distributor and vac can with only 1 hose connection and that goes to the base of my non-USA Aisin carb. So, assuming I had the original distributor and vac can, where does each connect to?
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On a desmogged USA 78 2F, the vac retard fitting is not connected. Vac advance hose goes from ported vac on carb base, to vac advance fitting on dissy.
Post a pic of your dissy so it can be identified.
Post a pic of your dissy so it can be identified.
Thanks Jim for your response. I will post up a pic of my dizzy connections. That single connection on the vac can next to my dizzy is running into the front of the carb by its base. I will post up pics of this. The top of my distributor itself obviously has the six wires coming off going to the plugs. One wire coming out of the center running to my aftermarket Accel coil and then two other holes. One of those holes runs a hose up into the passenger side of my air cleaner housing. The other hole at the top of the dizzy cap has nothing connected to it?? I will post pics of this as well. That hose running from the top of the dizzy cap into the air cleaner housing on the passenger side; I would have sworn someone said it may be causing a vacuum leak or lowering my vacuum pressure-is this possible? I still have low idle running issues and may need a neew brake booster as well. Opinions?
Will have pic up tomorrow
Jim here are more pics; first two pics are of the stock/original carb, existing dizzy-just one connection on can and it runs to the front lower medial area on the carb. Air cleaner connection thru thinner hose connect at top of dizzy cap. Existing non-USA Aisin carb, the line I am holding runs back to the top of the seperator with no charcoal cannister, OCV, VCV or blue BVSC anywhere along that line. And, because of my existing carb, no connection for it either. Hope these pics are usefull, I can take more. I need advice and how to get this rig running better. My single connection vac can, is that running vacuum retard????
pngunme says the vacant hole I have at the top of my dizzy cap runs a line into the cab thru the firewall. I have no smog stuff on my rig.
Also, blocked off aircleaner housing connection in that last pic(screw), what is supposed to connect there?
Assuming it's stock, it's a vacuum retard dizzy. If desmogged, you want to leave it disconnected and you will have mechanical advance only. The cat's meow would be a big-cap vacuum advance dizzy from an fj60 with matching side cover.
The air cleaner connection goes to one of the two ports on the dizzy cap and allows a small amount of air to be vacuumed from the breather in the cab, through the dizzy, to keep the cap from being full of ozone all the time. I think.
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My existing dizzy only has one connection on the vac can, on the side as seen in the pic-does that mean it is vacuum retard?
spotcruiser
Geezer
Yep. It's a retard.
Red hose from top of distributor cap should go to a filter on the firewall. It allows the air cleaner to suck a small amount of air through the dizzy while running.
Red hose from top of distributor cap should go to a filter on the firewall. It allows the air cleaner to suck a small amount of air through the dizzy while running.
I am not aware of any filter on my firewall, how should I connect-go thru firewall into cabin?
spotcruiser
Geezer
Post a pick of the passenger-side firewall (engine compartment). There'll be a small pipe (around 1/4" dia) sticking out or a hole where it belongs.
Never mind, I went out and got you a photo. The bolts above and below where the hose hits the firewall are the mounting bolts for the filter.
Never mind, I went out and got you a photo. The bolts above and below where the hose hits the firewall are the mounting bolts for the filter.
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So I am assuming I should disconnect that line going into lower front of carb and then block off the connection on the vac can? How will I get any advance then, I thought the '78 was vac advance and vac retard?
Thanks spot, I will look for that later and post up tomorrow.
Is that pipe down pretty low on the firewall and just runs into an outpocketing on the floorboard? Does it look like this-pic from below.
spotcruiser
Geezer
No, that's left over from your missing charcoal cannister. I added a photo to post #35.
spotcruiser
Geezer
Federal trucks had advance/retard. California was retard only (for vacuum). They still have some amount of mechanical advance. I seem to recall that somebody posted advance values just within the last day or two.
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