78 cj5 upper fresh air duct ???? by the newbie.

Transam87020

New member
Hello all,
I purchased a new to me 78 cj5 recently and while I have worked on numerous other cars in past, old mustangs and a current 81 TA I've never done a jeep. I pulled off the cowl vent as po said he sealed it due to a water leak. Well low and behold there is no upper vents at all in there. Further more none of the pics of the upper tract seem to match up with what I have. All the pics and diagrams I find show the main box that bolts to the cowl then a tract runs toward the pass side with a 90 degree elbow that connects to the heater air box. My box has no prevision for this elbow. Yep the top of the box is solid. Does anyone have an idea of where I can find the proper ducts or pics showing how this guy should be put together ? The po did mount a mojave heater under dash and is running the heater hoses through the firewall in a hole that I'm thinking could have been the factory drain hose. I'll attach a couple of pics of what I have. Thanks in advance for any and all assistance.
Chris
 

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As PoliceMonkey161 said, you need the upper half of the air plenum....that's the top part in his photo(the part is upside down in the photo). The opening at the elbow will connect with the lower duct(the bottom part in his photo).
Hope that helps...
 
The hoses coming from the Mojave would go the your water pump just like the factory hoses to heat your heater core in the Mojave heater. I thought the Mojave replaced the factory heater, if so maybe it just need finished installed and may be why your factory unit isn't working the way it should or is missing parts, I thought you had to run new duct for the defrost. I don't know much about the Mojave but that's what I have always heard.
 

Thanks all I figured what happened. I ran my hand along the top of the box and found a seam. Apparently the po cut a piece of plastic
or plexiglass and sealed off the hose where the upper elbow attaches. Not sure if I'll have to make up a way for it to attach as the block off is flush but the pic posted looks like it has a lip. The po also just spliced the Mojaves heater into the existing heater hoses so I have two heaters. I found a damaged upper on e-bay for $30 + shipping so I can try to get it functioning. I'd like to get everything functioning like original. Cant figure out why the po would pull the upper to block off the cowl vent or block off the lower. It works but just hate 1/2 A** work. Will I need to pull the front off the dash to get this installed ? I'm sure I'll need to find out where all the cables go also after I get into it.
I'd like to thank you all for the assistance, I'm sure I'll need to lean on you much more as I start this new adventure.

Chris
 
That's great that you will have two heaters once you get them up and working. Jeeps don't have the best heat for winter, so two heaters will really help.
 
I would recommend taking the dash plate off to re-install the correct OEM heater assm. Otherwise you're going to disconnect a bunch of wires that are hard to get too. It's confusing enough even if you've done it a few times. Plus with it being opened up, figuring out the cable controls will be easier. How broken is this one on ebay you found? I have a cracked one upstairs in the shop that is headed for the dump next time my son is home from College. (I think, unless I already chucked it?).
 

According to the seller it should be an easy fix. Figured a little fiberglass mat and resin and I'll be good to go. I'll need that air vent deflector I see in the diagram. The seller said he would throw in the drain hose so not to bad for $68 delivered I guess. Shipping was $38 ! I haven't seen the deflector on any pics I've seen r you guys using it or is it installed later ? Is the seal between the upper and cowl available ? Could make one from a window rope or something if not I suppose.
Attached a pic of what I bought, should be here Friday so we'll see. Thanks for the input, I'll look at pulling the dash plate off as you suggest police monkey. Looks like a fairly straightforward pull. Also dropped a pic of my toy in there.
Thanks,
Chris
 

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Anymore when I ship stuff I ship it on greyhound~way cheaper than ups, fedex and their ilk. When I sold the plastic 90* angle seats the P.O. had in 'BB' on EBay (for $45). This was for a box that was about the size of a wardrobe box, I used the shipping link for ups, and the freight was $138 just from here to Vancouver, WA (95 miles) I thought it was a mistake so I reloaded the page a couple of times and it kept on with that freaky high figure. Luckily I was able to contact the purchaser and shipped it on skinnymutt for $22 clams. Since then I've had really good luck with their shipping, especially with that 25% off coupon offer.
 
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