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Unread 03-04-2014, 05:58 AM   #31
Matt1981CJ7
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Quote:
Originally Posted by Purplehaze1786 View Post
How important is the canister purge? Debating on getting one.
The canister purge is part of the vapor canister. It's not a separate part.

The following components connect to the canister:

1. Fuel tank vent
2. Carb bowl vent
3. Purge signal
4. Purge line.

You can run without a vapor canister, but your CJ, garage, and clothes will always smell like fuel, especially after the engine is turned off. Not to mention the harm those vapors do to the atmosphere.

Here's an excellent pic from Keith.

Matt

keith-460-charcoal-canister-lines-vacuumhookup2.jpg

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Unread 03-04-2014, 06:30 AM   #32
Mike Romain
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Quote:
Originally Posted by Matt1981CJ7 View Post
(snipped)

It's for a Weber carb, so the vacuum ports are different then the BBD. Apparently, Gypsy has modified it to represent the Carter. I also don't care for some of the changes he's made, especially to the canister purge signal.
I don't think posting an incorrect diagram for a totally unrelated carb is very useful, more misleading than anything else.

Quote:
That said, I am an advocate of using manifold vac advance. It provides a smoother more efficient idle, better cold starts, and better low-end performance. I've never experienced any boggy start-offs as a result of using manifold vac advance. The debate continues......

Matt
I figure it is Real easy to find out how your Jeep runs each way, so I would just try it both ways.

Ported timing gives mine no ripples in a glass of beer on the air filter at idle, burning rubber if I punch the gas pedal too hard off a start and at 7 this AM at -20C, it fired right up first revolution of the engine.

Makes 'me' happy.
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Unread 03-04-2014, 06:44 AM   #33
Matt1981CJ7
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Quote:
Originally Posted by Mike Romain View Post
I figure it is Real easy to find out how your Jeep runs each way, so I would just try it both ways.
I have tried it both ways, and there's no comparison, in my book.

The only practical difference between manifold and ported vac is at idle. Since engine vacuum is high at idle, the A/F mixture is lean relative to other times. A lean mixture takes longer to burn efficiently. Manifold vac adds advance at idle, when the engine needs it most.

I also note that AMC used strictly manifold vac advance on 83-86 models according to my research.

If you're happy, I'm happy, John. I've enjoyed your return to the forum.

Matt
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Unread 03-04-2014, 06:55 AM   #34
Mike Romain
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Quote:
Originally Posted by Matt1981CJ7 View Post


I also note that AMC used strictly manifold vac advance on 83-86 models according to my research.
The computer had control there also. The distributor advance was different too.

Quote:
If you're happy, I'm happy, John. I've enjoyed your return to the forum.

Matt
Lol, Matt you seem to have me mixed up with someone named John.

Mike
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Unread 03-04-2014, 07:04 AM   #35
Matt1981CJ7
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Mike,

I'm so sorry for the name typo. Not enough coffee, yet.

As I understand it, the computer had nothing to do with the vac advance. Also, I've torn apart both feedback and non-feedback Motorcraft distributers. The only differences I've found is in the centrifugal slots on the advance head, and the weight of the springs. The vac advance canisters were identical.

Matt
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Unread 03-04-2014, 07:10 AM   #36
Purplehaze1786
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Ok so now that you mention it, i have noticed a lot of fumes/smell of gas. So maybe i'll go with a purge canister. Is there a certain brand I should get? I saw some cheap ones online at Advanced auto..for like $30 to $100. Most only had 2 ports on top. I'm guessing i need atleast 3....1 for the vacuum....1 for the gas tank vent...an 1 for the carb bowl vent.?????
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Unread 03-04-2014, 07:13 AM   #37
Mike Romain
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Quote:
Originally Posted by Matt1981CJ7 View Post
Mike,

I'm so sorry for the name typo. Not enough coffee, yet.

As I understand it, the computer had nothing to do with the vac advance. Also, I've torn apart both feedback and non-feedback Motorcraft distributers. The only differences I've found is in the centrifugal slots on the advance head, and the weight of the springs. The vac advance canisters were identical.

Matt
The computer controls the purple wire going to the pickup coil in the distributor so it sure has some kind of timing control. Knock sensor in there too.
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86/00 CJ7 Laredo, 33x9.5 BFG AT's, 'glass nose to tail in '00, 'New' frame,wires and plumbing in '09. Carter BBD Carbed 4.0 HO in '10.
89 YJ Renegade. BBD Carbed 4.0 HO. Locked front and rear with 33x9.5 BFG AT's
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Unread 03-04-2014, 07:28 AM   #38
Matt1981CJ7
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Quote:
Originally Posted by Mike Romain View Post
The computer controls the purple wire going to the pickup coil in the distributor so it sure has some kind of timing control. Knock sensor in there too.
Yes, the computer had control over centrifugal advance, not vac advance.

If you look closely at the '83-86 49-state vacuum layout below, you can clearly see the vac advance has a direct manifold vac signal. Yes, other devices shared that signal, which some claim had a buffering affect on the vac advance, but my tests haven't proven that to be true.

Matt
vacuhose.png

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Unread 03-04-2014, 07:52 AM   #39
Mike Romain
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Quote:
Originally Posted by Purplehaze1786 View Post
Ok so now that you mention it, i have noticed a lot of fumes/smell of gas. So maybe i'll go with a purge canister. Is there a certain brand I should get? I saw some cheap ones online at Advanced auto..for like $30 to $100. Most only had 2 ports on top. I'm guessing i need atleast 3....1 for the vacuum....1 for the gas tank vent...an 1 for the carb bowl vent.?????
The float bowl vent isn't the main player, but it can just T fit to the gas tank vent line if there isn't a special nipple for it. You need the activated charcoal container to store the fumes when it sits and a purge signal to vent it into the PCV line when the engine is warmed up and at speed. (Means ported signal via the CTO valve)

This also balances a stock PCV system so it vents the crank properly too which controls engine sludge and the 'vacuum leak' created by this purge balances the high speed carb mix.

All I all I find they just run better with the canister in place and working.
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86/00 CJ7 Laredo, 33x9.5 BFG AT's, 'glass nose to tail in '00, 'New' frame,wires and plumbing in '09. Carter BBD Carbed 4.0 HO in '10.
89 YJ Renegade. BBD Carbed 4.0 HO. Locked front and rear with 33x9.5 BFG AT's
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Unread 03-04-2014, 08:06 AM   #40
Matt1981CJ7
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Quote:
Originally Posted by Purplehaze1786 View Post
Ok so now that you mention it, i have noticed a lot of fumes/smell of gas. So maybe i'll go with a purge canister. Is there a certain brand I should get? I saw some cheap ones online at Advanced auto..for like $30 to $100. Most only had 2 ports on top. I'm guessing i need atleast 3....1 for the vacuum....1 for the gas tank vent...an 1 for the carb bowl vent.?????
I don't think the stock vapor canister is available any more.

However, you can use one for a mid-90's Jeep Grand Cherokee. One port has to be drilled out, but otherwise it's plug and play. I like the Cherokee canister better because it vents from the top side, instead of from the bottom where the element always gets caked with mud.

Here's a good write-up on it.

Matt
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Unread 03-10-2014, 09:16 AM   #41
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Ok, I tried to make this easier for me to understand. Hopefully you guys can steer me in the right direction. The choke is not being used. The EGR valve has no connection going to it. And there is no charcoal canister. Let me know if i have these ports all hooked up right an capped or uncapped.
100_1692.jpg   100_1696.jpg   100_1697.jpg  
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Unread 03-10-2014, 09:28 AM   #42
Mike Romain
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Quote:
Originally Posted by Purplehaze1786 View Post
Ok, I tried to make this easier for me to understand. Hopefully you guys can steer me in the right direction. The choke is not being used. The EGR valve has no connection going to it. And there is no charcoal canister. Let me know if i have these ports all hooked up right an capped or uncapped.
The writing is hard to read on my phone, but it looks decent.

Your gas filter should be turned so the return line is at the top to make for way easier cold starts.

Carb vents open to the air.

I use the nipple on the valve cover side for my distributor advance. Some others use the nipple on the drivers side for this, your choice. We both think our ways work best for our engines.

I couldn't see in the nipple under the choke pull off. If not used for the choke it should be capped. Bottom back corner on the passenger side.
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89 YJ Renegade. BBD Carbed 4.0 HO. Locked front and rear with 33x9.5 BFG AT's
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Unread 03-10-2014, 10:46 AM   #43
SouthernGypsy
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For what you described with no canister and if you intend not to use your EGR then;

A) Needs to be capped, it's not a vacuum leak if uncapped but will allow dust, crud, and moisture into your carb.
B) Correct but you need to replace your PCV valve with one from a 1984-86 model that only has a single port instead of an T or F on top.
C) Correct, goes to PCV valve. Would also T to the canister IF you had one which is why your current PCV valve has the T style top.
D) Goes to your choke pull off, if your not using that then cap it.
E) Capped.
F) Capped.

If D, E, or F are uncapped and unused then you will have a big (or several) vacuum leaks when it's running so all of those need to be capped.

You should really consider getting the kit to reconnect your choke pull off, reconnect that line, and get your choke working properly. You will be a lot happier with your cold starts. Hooking up your EGR valve will also make your combustion chambers run a little cooler extending the life of your engine. That normally hooks to the line you show to be capped (shown in the first picture you didn't mention it) on the bottom front left corner of the carb, preferably thru the CTO if you can.

I can also see two, maybe three problems in your first picture;

First is that your fuel filter is in the wrong position, the return line should be in the 12 O'clock position directly above (higher) than the line that goes to the carb.

The second which is a very dangerous one is that your return line from your fuel filter is also in a very dangerous location, someone has routed it down between two of the intake manifold runners right next to the exhaust manifold. That's just asking for it to vibrate over against the manifold and someday melt or rub thru the line which will result in a nice little Jeep bon-fire when the fuel starts to flow out onto the hot exhaust manifold. You should come out of the fuel filter and then curve it off toward the drivers side fender and down to the line from the tank, away from the engine and especially the exhaust manifold.

Third which I am not as sure about is that I don't see any gaskets showing between your carb and the carb spacer nor the carb spacer and the manifold. If not you may have a leak there. Usually you can kind of see the edges of them if they are there and I don't see any. It's possible I just can't see them good due to the angle of the picture so I'm not certain about that one.

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Unread 03-10-2014, 11:06 AM   #44
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This shows a simplistic diagram of how the connections would normally be in a simple setup like yours, well except that it does not show the small center port on the carb in back but we all know that goes to the choke pull off if you have one. Whatever your not using you cap off properly.
_
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Unread 03-10-2014, 11:43 AM   #45
Mike Romain
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Quote:
Originally Posted by SouthernGypsy View Post
This shows a simplistic diagram of how the connections would normally be in a simple setup like yours, well except that it does not show the small center port on the carb in back but we all know that goes to the choke pull off if you have one. Whatever your not using you cap off properly.
_
You know sir, I just don't like your diagrams or your knowledge of the BBD carb sorry.

The BBD has a rear center port for the PCV which comes from the front baffled hole in the valve cover. It has a corner port for the choke pull off as all of us don't seem to know..

Edit: including me it would seem.... Just looked at my spare and you are correct on that one.

The EGR also is supposed to route through a thermostat in the air filter so it doesn't open if you have -40 temps sucking in there which would really cause a bog.
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89 YJ Renegade. BBD Carbed 4.0 HO. Locked front and rear with 33x9.5 BFG AT's
Some Canadian Bush Jeep Runs and Build Photos: http://mikeromainjeeptrips.shutterfly.com (10 new albums added Sept 16/10)
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