Yj runs like new, but have 4wd light question - Off-Road Forums & Discussion Groups
Jeep-Short Wheelbase All discussion of short wheelbase Jeeps: CJ, TJ, YJ and JK

Reply
 
LinkBack Thread Tools Display Modes
post #1 of (permalink) Old 04-10-2002, 09:58 PM Thread Starter
 
Join Date: Oct 2001
Posts: 409
Thanks: 0
Thanked 0 Times in 0 Posts
 
Yj runs like new, but have 4wd light question

Last weekend we nuttered the YJ, replaced the valve cover gasket, and replaced the fuel pump. Riped all of the vaccum lines and such out of it. IT no longer blows smoke at stat up, STARTS and SHUTS off. The 258 now has a longer but steady power band.

Since the 4wd light has never worked on the YJ since it had 15,000 miles on it and now has 97,000 we thought it was time to check it out. The switch works fine. Power was sent to it and the interior panel light came on. It also came on when i sucked on the vaccum line. The Shoft motor works fine and shifts into 4wd no porblem, just my light does not come on. All of the lines are on tightly. A local personal dealer said he ordered a shift motor on accident and it cost 130 dollars, does this sound right?
87Warrior is offline  
Sponsored Links
Advertisement
 
post #2 of (permalink) Old 04-10-2002, 10:21 PM
 
Join Date: Dec 2001
Posts: 965
Thanks: 0
Thanked 0 Times in 0 Posts
 
Re: Yj runs like new, but have 4wd light question

have you tried removing the vacuum hose for the 4WD light from the vacuum motor at the vacuum motor. On mine its the black hose on the left most part of the motor. once it engages put your finger over, see if you got suction. there is a check valve floating around in there some where or maybe the tube is pinched.
speed_buggy is offline  
post #3 of (permalink) Old 04-11-2002, 03:32 PM Thread Starter
 
Join Date: Oct 2001
Posts: 409
Thanks: 0
Thanked 0 Times in 0 Posts
 
Re: Yj runs like new, but have 4wd light question

IF there is no vaccum what do i do? Buy a new shift motor so my light comes on for 130 dollars?? If that is the case i would rig an electrical switch to run the light some how.

There is another problem. The YJ is running rich i believe. After the nutter it will drop from 60mph to 55mph going up a hill, and before with the computer it would stay at 60-petal to the metal- How could i check this? Will i possibly need to change the main jets, if so where do i get them from? I have not adjusted the air/idle mixture screw, will that help much at all?
87Warrior is offline  
Sponsored Links
Advertisement
 
post #4 of (permalink) Old 04-11-2002, 09:35 PM Thread Starter
 
Join Date: Oct 2001
Posts: 409
Thanks: 0
Thanked 0 Times in 0 Posts
 
Re: Yj runs like new, but have 4wd light question

I crawled under the hood and the vaccum was hooked up all wrong. It looks like battery acid dopped down on to the hoses and melted them. I fixed that and tried the light. Now it will not shut off. There is always vaccum presnt at the switch. I checked the check valve and it works fine. Where do i go from here? Can somebody please post a picture of their area below the battery holder? I am going to a local dealership to take a gander at one of their YJ tomorrow.
87Warrior is offline  
post #5 of (permalink) Old 04-11-2002, 11:28 PM
 
Join Date: Sep 1999
Posts: 3,478
Thanks: 0
Thanked 0 Times in 0 Posts
 
Re: Yj runs like new, but have 4wd light question

You said the light stays on continuously...does the shift motor shift out of the locked(4wd) position?

The vacuum disconnect system on the YJ is very similar to the one on my 1986 XJ.
The green tube is the 2wd connection it connects to the port closest to the passenger side tire. The yellow is the 4wd connection; it goes on the middle port. The dash light connection is the port closest to the differential.

There should be a red tube running from the vacuum cannister under your battery tray that goes to the transfer case switch. This is the main vacuum source for the disconnect front axle.(not completely sure about this as the vacuum source location on my 2.8 XJ is different from your YJ). There is also a blue tube with a check valve on the end of it. This is a vent and should not be connected to anything.
xjy173 is offline  
post #6 of (permalink) Old 04-13-2002, 01:12 AM Thread Starter
 
Join Date: Oct 2001
Posts: 409
Thanks: 0
Thanked 0 Times in 0 Posts
 
Re: Yj runs like new, but have 4wd light question

Got a vaccum gauge today, here is what i found out. For more than 40,000 miles the yj's axel has been locked in 4wd. The shift motor functions properly when applying vaccum to it. My green line has NO vaccum at all. I have determaned, with the help of a dealer who had a simular problem, my switch on top of the trasnfercase is broke. In Quadratec they are 13 dollars and i believe from the dealership they are 50 dollars. The choice is simple right? Nope, Quadratec has discontiniued the switch. Going to purchase a new one tomorrow at the dealer.
87Warrior is offline  
post #7 of (permalink) Old 04-15-2002, 11:30 AM
 
Join Date: Jul 2000
Posts: 220
Thanks: 0
Thanked 0 Times in 0 Posts
 
Re: Yj runs like new, but have 4wd light question

hold on now. disconnect the lines running to the switch on the tcase. there should be four:

1)constant vaccum from the motor
2)vent
3)line running to the 4wd port on the shift motor
4)line running to the 2wd port on the shift motor

hook the vacuum tester up to the port on the vacuum switch that is for the constant vacuum, shift into 2high, pump the tester with your finger over on of the 3 other holes so it holds vacuum. shift into 4high and do the same thing. THEN if you cover up the same hole for 2high and 4high your vacuum swith is bad. if the ports switches the vacuum switch is fine and you have a leak in one of the four lines.
mcYJ is offline  
post #8 of (permalink) Old 04-15-2002, 02:27 PM
**DONOTDELETE**
Guest
 
Posts: n/a
Re: Yj runs like new, but have 4wd light question

Red is vaccum, blue is vent. Green and Yellow engage or disengage the front end. The transfer case switch in my 89 went bad a year ago (stuck in 4WD), and had to replace it. I found one at NAPA for $12 or so. Very easy to replace. Since then, the plastic tubes have broken near the front and the whole harness ended up laying on the exhaust and melting. Someday, I'll upgrade to the hand-operated cable.
post #9 of (permalink) Old 04-15-2002, 04:36 PM Thread Starter
 
Join Date: Oct 2001
Posts: 409
Thanks: 0
Thanked 0 Times in 0 Posts
 
Re: Yj runs like new, but have 4wd light question

Went to the Jeep Dealer and orderd the Vac. Switch. IT cost 16 dollars total. The front shift motor holds Vaccum for ever.

Since there was much jerry-rigging done to my vaccum set up, is there a vaccum line going from the vent hose to any where? Mine was attached to the yellow. That did not seem right. Any help?
87Warrior is offline  
post #10 of (permalink) Old 04-15-2002, 05:45 PM
 
Join Date: Sep 1999
Posts: 3,478
Thanks: 0
Thanked 0 Times in 0 Posts
 
Re: Yj runs like new, but have 4wd light question

The blue vent line should not be attached to anything; it should have a check valve on the end of it. It should not go to the axle shift motor. Maybe the check valve got lost with the vacuum replumbing.

Normally, the yellow tube is the 4wd connection, meaning that when you shift into 4wd, the yellow tube has vaccuum.
xjy173 is offline  
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Off-Road Forums & Discussion Groups forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome