[TOM85CJ7]

I would like to increase my understanding of the vacuum system on my '85 CJ7 w/258. I don't really know where all of the hoses are supposed to be connected and what all the various connectors are for. Could someone please explain the purpose of all this stuff and the basics behind the system, or point me to a page that has this information. I am not intereseted in removing everything, I just want to understand how it should be connected properly.

Thanks,
TOM85CJ7

1985 CJ7 4.2L, T-176, Dana 300, 2.5" lift, 32"BFG MT, Durabak On-Board Air

 

[Dirt Dog]

Sorry I don't have a good answer other than the manuals have a full rundown on the complete vacume system.
On the bright side/wwwthreads_images/icons/smile.gif it was a good way to lighten my jeep/wwwthreads_images/icons/crazy.gif

85'CJ7 258 4" runnin33's

 

[Guest]

check out http://www.off-road.com/jeep/tech/258bbd/vacuhose.htm
see if that helps.

 

[Smokngun]

All of those vacum lines really do nothing for your engine. Actually after '82, Jeeps didn't have internal combustion engines. The vaccum lines really run a reverse ossmosis machine that powers your Jeep through the evaporation of hydrogen steam. The engine block is just there to bolt everything too./wwwthreads_images/icons/wink.gif Seriously, does anyone REALLY understand why all thise vaccum lines are there (in my '83 also). I look under the hood of my '99 Dakota and it is nearly free of those pesky rubber hoses, and I ask myself...WHY?

Mike H.
1983 CJ-7 Laredo
1999 Dakota 4x4
/wwwthreads_images/icons/cool.gifo[[[[o

 

[TOM85CJ7]

If anyone has questions about where all of those hoses are supposed to go, I now know. I spent several hours yesterday tracing all of the hoses and basically connecting every one of them. I even have a basic understanding of what they do. Most of my knowledge is based on the following pages:
http://www.off-road.com/jeep/tech/258bbd/index.htm
This primer is a great guide for those of you who have an intact emissions system, it can be very helpful in diagnosing problems with individual items in the system.

Let me know if you have any questions.

TOM85CJ7

1985 CJ7 4.2L, T-176, Dana 300, 2.5" lift, 32"BFG MT, Durabak On-Board Air

 

[171]

If it wasn't for all of those vacume lines think how many mechanics would be unemployed.As far as your "99 Dakota goes it is run by computer chips that is really beyond the range of normal human comprehension /wwwthreads_images/icons/smile.gif
It is like ending the "war on drugs" what would you do with an unemployed ,gun packing army of unemployed drug agents,maybe turn them into smog police HUH ?
Seriously though you kinda have to study and analyze one line or system at a time or it is like trying to learn a foreign language in one day.It will drive ya nuts if one thing is out of wack.Try to get a diagram of your SPECIFIC year and engine and model because the chilton diagrams are way off compared to the service manual for your vehicle,and the service manual has probably a dozen different diagrams in it for the one year I have.A vacume gauge or a hand vacume pump is pretty necessary to test the components.

Learn to let go of what does not serve you ,but forces you to serve it

 

[TOM85CJ7]

I used the engine diagram by the radiator in conjunction with the infoe in the "Primer". After reading everything about three times and really studying all of the components it was actually pretty easy to figure out. Just go slow and don't disconnect everything at once.

1985 CJ7 4.2L, T-176, Dana 300, 2.5" lift, 32"BFG MT, Durabak On-Board Air