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  #1  
Old 07-18-2000, 07:27 PM
bignblue
 
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Question

Before I get started, props and kudos to Porkchop for getting me in touch with a good speedo. I now know exactly how fast (umm, slow) I'm driving! I repainted the chrome trim with some GM metallic silver touch-up and it looks "good 'nuff" close.

Now to my issue o' the day: I noticed today that when I shut my Chero off, I smelled something burning. I popped the hood--lo and behold, smoke! It was coming out of the pass. side exhaust manifold. There's this coke-can sized hole pointing upwards that connects to absolutely nothing. Is this some type of EGR port or something? Should I cap it off or try to find the correct part for it?

------------------
'78 Chero WT
401/4bbl/TH400/QT
44s F&R
"Jeep: the toughest 4-letter word on wheels"
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  #2  
Old 07-19-2000, 05:00 AM
BobBarry
 
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<BLOCKQUOTE>quote:</font><HR>Originally posted by bignblue:
Now to my issue o' the day: I noticed today that when I shut my Chero off, I smelled something burning. I popped the hood--lo and behold, smoke! It was coming out of the pass. side exhaust manifold. There's this coke-can sized hole pointing upwards that connects to absolutely nothing. Is this some type of EGR port or something? Should I cap it off or try to find the correct part for it?
<HR></BLOCKQUOTE>

That is where the pre-heat hose from the air-cleaner attaches. When the engine is cold, the flap in the air-cleaner snorkel directs air from a flex-hose that feeds from the space around the manifold that is boxed in by sheetmetal. This provides warm air as soon as possible to the engine, improving cold-weather driveability. You may have just fried a mouse's home, or it may be some old solvent or oil burning off. It should not be open to the exhaust itself, though.

------------------
Bob Barry<UL TYPE=SQUARE>* '78 Cherokee 4-door
* '88 Grand Wagoneer[/list]http://studentweb.providence.edu/~rbarry/wheels/
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  #3  
Old 07-19-2000, 07:39 AM
porkchop's Avatar
porkchop porkchop is offline
Master of B.S.
 
Join Date: Apr 17, 2000
Location: Corpus Christi, TX 78414
Posts: 8,125
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You are very welcome! If there is anything else that you need feel free to ask.

------------------
'67/'79 Wagoneer mix
Body of a 33 year old
Heart and legs of a 21 year old.
360,TH400,QT,D44's F&R
32X11.50's

"I regret that I have but only one paycheck to give to my Jeep."
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  #4  
Old 07-19-2000, 08:39 AM
Veepster Veepster is offline
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Join Date: May 14, 2000
Location: State College, PA USA
Posts: 1,366
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my guess would be a leaking valve cover gasket....look for crud between the bottom of the valve cover and the top of the exhaust manifold, if there is an accumulation of crud there, either live with the puffs of smoke or change the valve cover gaskets..

Peace.................BartG
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  #5  
Old 07-19-2000, 07:21 PM
bignblue
 
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Wink

Dr Barry--how hard would it be for me to find parts to fix this? Not that Alabama is especially cold, but I've noticed a tendency for my vehicle to stall out when the motor's cold. Where should I start looking? Also, I haven't noticed any gaping holes in the air cleaner housing--where does the hose go?

PorkChop--be careful what you ask for, you just might get it!

BartG--my valve covers are crusty as all get-out along the flanges, so a gasket replacement is my next job. I'm gonna sand and repaint 'em, too.

------------------
'78 Chero WT
401/4bbl/TH400/QT
44s F&R
"Jeep: the toughest 4-letter word on wheels"
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  #6  
Old 07-20-2000, 02:32 AM
BobBarry
 
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<BLOCKQUOTE>quote:</font><HR>Originally posted by bignblue:
Dr Barry--how hard would it be for me to find parts to fix this? Not that Alabama is especially cold, but I've noticed a tendency for my vehicle to stall out when the motor's cold. Where should I start looking? Also, I haven't noticed any gaping holes in the air cleaner housing--where does the hose go?<HR></BLOCKQUOTE>

There should be a circular opening on the bottom of the air-cleaner snorkel, just about above where that hole in the shroud around the exhaust manifold is. You buy a piece of appropriate-sized flexible pre-heat hose (aluminum color) at your local Pep-Boys, slide one end over the shroud on the manifold, and snake the other up to the connection on the bottom of the snorkel.

When the engine is cold, vacuum from the engine closes the trap door in the snorkel and draws air through that pre-heat tube. Once the engine warms up, a temp-sensor in the air-cleaner shuts off the vacuum, and the engine draws cooler air through the flex-hose that runs from the air-cleaner to the opening to the grille in the front radiator support (right next to the battery).

Most used FSJ's are missing both these hoses, but it's only about $15 to replace both, and they'll improve driveability considerably.

Before you install the hoses, however, verify that the flap in the snorkel is shut when the engine is started cold, and opens when it warms up. It's not uncommon for the vacuum lines to the snorkel to be disconnected or misrouted.

------------------
Bob Barry<UL TYPE=SQUARE>* '78 Cherokee 4-door
* '88 Grand Wagoneer[/list]http://studentweb.providence.edu/~rbarry/wheels/
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  #7  
Old 07-20-2000, 03:31 AM
Veepster Veepster is offline
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Join Date: May 14, 2000
Location: State College, PA USA
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one addition to the ALWAYS incredibly helpful Dr Barry's post.....

the flap should also open momentarily when you stab the throttle.

Peace..................BartG
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  #8  
Old 07-24-2000, 09:20 PM
bignblue
 
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Smile

I'm hoseless, but thanks to the good Doctor not completely hosed. I didn't notice a bracket by the radiator support to mount the hose mouth on, though. As for vacuum to the snorkel, my vac lines are so screwed that I don't know where to begin! There are three (around the back of the carb) that are plugged with sheet metal screws or little pieces of cork. I know squat-all about vac lines and I seem to have lost the drivetrain TSM that came with my Jeep. The closest FSJ-specific mech is in Birmingham so it looks like I'll be making a drive soon. Thanks!

------------------
'78 Chero WT
401/4bbl/TH400/QT
44s F&R
"Jeep: the toughest 4-letter word on wheels"
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  #9  
Old 07-25-2000, 06:30 AM
BobBarry
 
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<BLOCKQUOTE>quote:</font><HR>Originally posted by bignblue:
I'm hoseless, but thanks to the good Doctor not completely hosed. I didn't notice a bracket by the radiator support to mount the hose mouth on, though.<HR></BLOCKQUOTE>

To the left of the battery, there should be a rectangular opening, ideally with a plastic "lip" to slip the hose over (which is also rectangular).

<BLOCKQUOTE>quote:</font><HR>As for vacuum to the snorkel, my vac lines are so screwed that I don't know where to begin! There are three (around the back of the carb) that are plugged with sheet metal screws or little pieces of cork. I know squat-all about vac lines and I seem to have lost the drivetrain TSM that came with my Jeep. The closest FSJ-specific mech is in Birmingham so it looks like I'll be making a drive soon. Thanks!
<HR></BLOCKQUOTE>

The hookup to the snorkel is easy. One hose from direct manifold vacuum (there should be a port right behind the carb, on the manifold itself), to the thermostatic switch on the air-cleaner housing (it's round on the inside of the housing, and has two little nipples sticking through the bottom of the housing, with clips holding them on), and then another hose from the unused nipple on that switch to the vacuum port on the vacuum motor on the snorkel itself.

As for poor driveability, getting the hoses in order would help you attain that goal.

Look at the following site, which has vacuum diagrams for a '76, which would work for your '78 as well:
http://www.slidingdelta.com/fsj/wagoneer.html

There are also '78 vacuum diagrams at:

http://home.off-road.com/~ifsja/tech/index.htm

if you can catch them when the server is up...

------------------
Bob Barry<UL TYPE=SQUARE>* '78 Cherokee 4-door
* '88 Grand Wagoneer[/list]http://studentweb.providence.edu/~rbarry/wheels/
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  #10  
Old 07-25-2000, 09:58 AM
JERRY88GW JERRY88GW is offline
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Join Date: Jun 09, 2000
Location: Alexandria, VA, USA
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I have no opening on my exhaust manifold for the pre-heat hose to go to. I do however have an opening on my air cleaner housing.

Did some GW's not come with this?

It's an 88 GW.

Thanks
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  #11  
Old 07-26-2000, 01:47 PM
BobBarry
 
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<BLOCKQUOTE>quote:</font><HR>Originally posted by JERRY88GW:
I have no opening on my exhaust manifold for the pre-heat hose to go to. I do however have an opening on my air cleaner housing.
Did some GW's not come with this?
<HR></BLOCKQUOTE>

They all came with one; in most all cases, it rusts away and falls off

------------------
Bob Barry<UL TYPE=SQUARE>* '78 Cherokee 4-door
* '88 Grand Wagoneer[/list]http://studentweb.providence.edu/~rbarry/wheels/
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  #12  
Old 07-26-2000, 03:55 PM
ClarkGriswald's Avatar
ClarkGriswald ClarkGriswald is offline
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Join Date: Jul 03, 2000
Location: Bloomingdale MI , USA
Posts: 1,477
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Nothing like a piece of sheet metal bolted to a piece of cast iron that gets super hot.. those things are destined to rot off.. mine is still there but looks like a hundred year old abandoned shack.

------------------
88 Grand Wagoneer
D44's front\rear
AMC 360
TF 727
NP 229 (Funky)
Bone Stock (for now)
NO RUNNING BOARDS!
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