Vacuum Loss?

[LostWolf]

Got in the Wagon this morning to come to work. Didn't drive it at all this weekend. When I went to turn the heat on there was not much air coming out. Not much difference between high, medium, and Low. When I got to work I left it on and opened the door and it sounds like you can hear the fan blowing just fine. I also could not get it to go into 4x4. I tryed all the normal trick but nothing. I also noticed its running rough when I stopped at a stop sign.

I haven't had a chance to take a look yet I will when I get home tonight. Have I lost a vacuume line somewhere or what. Any suggustions as to where and what to look for?

Thanks guys. Its good to be back. I've been gone for a while for work and haven't been able to check whats been going on.



------------------
LostWolf
87GW "SuperWagon"
360AMC, 727, NP229(Replaced),
MotoCraft 2150 (Rebuilt), D44s,
Master Craft Courser Tires
No Modifications, Yet!
TybowKites@hotmail.com
www.geocities.com/yosemite/gorge/1372 (http://www.geocities.com/yosemite/gorge/1372)

[Veepster]

definitley sounds like a vacuum hose is loose.....it should be very obvious, if not spray around the base of carb w/ carb cleaner....when you hit the right spot your idle will change...

------------------
Peace.............BartG

the Green Flash!
360ci
Custom 4v TBI
Edelbrock Performer Manifold
TH400, QT with low
4" skyjacker Rancho 9000's
33x12.50 BFG KO's 8" American Racing Baja Rims
Thorley headers, 3" exhaust, Dyno Max
Infiniti power leather seats
Custom billet shift knob by Millerluck
50%Luxury Car, 50%Tractor
http://www.teamgodspeed.com

[Ralph]

There's a black softball-sized vacuum canister right in the center of the firewall that controls vacuum to the heat/defrost flap. Check to see that a hose is attached to it. Sometimes the tiny recessed nipple will break off, and the hose won't have a place to attach.

------------------
J ust
E mpty
E very
P ocket

[LostWolf]

The black orb was the first place I will look but does that have anything to do with the 4x4 switch?

[River Beast]

the black ball is a vac reservoir... it maintains vacuum constants for running other vac operated stuff like the 4WD and heater ducts between floor/dash/defroster. You may have a vac line off somewhere near there or a cracked, dryrotted line near a fitting...

------------------
Todd
78 Wagoneer, "River Beast"
360/TH400/QT
Dana 44's locked w/ 4.89's
39.50x15x15 Super Swamper TSL's
7" SOA in front-7" Rear Shackle Inversion Mods
4" Skyjacker Softride
3" Trailmaster Bodylift
My FSJ site: http://www.geocities.com/spazz4life (http://www.geocities.com/spazz4life)
My E-mail: monster_fsj@hotmail.com
"If you can't stop...SMILE as you go under!"

'93 3/4 ton 4x4 Suburban...a.k.a. "FSJ Hauler"

[LostWolf]

Well I went out last night and looked around for a disconnected vac hose and didn't find one. I did find that the black ball was cracked open. Took it in and JB Welded it back together. Put it back on this morning and still no change.

Any other tips?



------------------
LostWolf
87GW "SuperWagon"
360AMC, 727, NP229(Replaced),
MotoCraft 2150 (Rebuilt), D44s,
Master Craft Courser Tires
No Modifications, Yet!
TybowKites@hotmail.com
www.geocities.com/yosemite/gorge/1372 (http://www.geocities.com/yosemite/gorge/1372)

[reddog]

Your symptoms have all the signs of a vacuum leak. Try getting a vacuum connector that fits the vacuum lines that go in/come out of the "black ball" and use it to connect those lines, bypassing the ball, and see if that fixes your problems. That will tell you if the black ball is the source of your leak.

------------------
87 GW - Stock (but it looks like RiverBeast when I'm sleeping)
TFI upgrade
360,727,NP229

[LostWolf]

I found it. Well it wasn't the black ball even though that did need to be fixed. I followed the 4wd vacuum diagram (Hard to read) because that wasn't working either. I turned out to be a hose disconnected from the intake manifold directly behind the carb. Hooked it back up and I have heat and 4x4 back. YAHHOOOOO. Its cold up here it da UP.

This raises a question however. It appears that my 4wd and heater controls run off the soup can vacuum resivor. What runs off the black ball?

[Ralph]

Sounds like your lines are crossed. The soup can is for the cruise control.

[andy d]

sounds like you got CPOed (Cheap Prior Owner) http://www.ifsja.org/ubb/biggrin.gif he prolly moved every thing to the soupcan stedda fixin the ball.

[LostWolf]

If you look at the diagram in the tech section. http://www.ifsja.org/tech/tcase/seltrac.shtml
It shows the 4wd going to the soup can. Does anyone have diagrams that show the proper hook up for the nonemissions stuff. I don't see much in the Haynes book.

[Ralph]

I just went out and looked at mine. The soup can has two outlets as in that diagram: one of them snakes back to the cruise control; and another goes to the black orb on the firewall, with a T-fitting that goes to the manifold (purple check valve in line). So I don't know where the vacuum for the Selec-Trac is contained.

[LostWolf]

Thanks Ralp I'll go look tonight when I get home. Can't remember were my black orb is feed from. One line goes to the air cleaner I beleive.