rgs80074

Hello Everyone,

I recently purchased a 1996 jeep grand cherokee limited after my 98 grand cherokee was totaled in an accident.

This new jeep actually had working ac but after asking some questions and such on this forum I learned that the blower motor was not working on the jeep and they had replaced it with an aftermarket one, one that's good, but I don't think the force of the air coming out of the vents are nearly as strong as it should be, yes I have the various degree's but all of them are weaker than I think they should be.

I don't think they took out the old bad blower motor and correct me if I am wrong but if they didn't and the new aftermarket one was put in does it not basically have to turn that or gets its forced blow slowed down by the non working one?

thanks

Ryan

dave1123

No, there's only room for one and it's mounted in the bottom of the heater plenum behind the glove box. What you may have is either the recirc door or the blend door blocking the discharge from the blower. My '97 had this problem with the blend door (temp control) blocking the flow. The fan sounded like a hurricane trying to get thru a keyhole and just a trickle of air coming out the ducts. It was barely enough to clear the windshield on defrost. A broken blend door shaft is a common problem with jeeps and there are many posts here on how to fix it. Most common fix is to cut an access hole in the plenum and install an aftermarket door. It's a lot easier than removing the whole dash.

rgs80074

Ok,

Most of that was way above what I understood.

If the prior person installed an aftermarket blower motor (was shown in another post of mine due to the wiring job) wouldn't that mean the old blower motor is still there inside the unit?

Ryan

dave1123

No, as I've said, there is no place to install a second one and the fan is mounted on the bottom of the air box underneath the glovebox. If you take out the 3 screws that mount it, you should be able to look straight up and see the air entrance hole in the cowl. If either door is broken, you'll see it obstructing the airway. The original fan motor is covered with a plastic housing and the aftermarket ones aren't. One other thing might be the wiring is wrong so the fan is running in reverse. That is easily fixed by switching the 2 wires.

Bugout4x4

I had this happen to me on my 97 and it turned out to be a broken vacuum line that was not letting the HVAC doors change far enough to work correctly. I found the leak at a broken plastic line between the Cruise Control and the Vacuum Reservoir mounted under the frame behind the Passenger side Front Bumper.

I would start by checking all of your Vacuum Lines. 1/8th inch Rubber Vacuum line will fit over these Plastic Lines tightly to connect and seal.

rgs80074

How would I be able to tell if its blowing backwards? Is there a way to test for this and remember I am not a mechanic by any means but I am learning little by little but I don't have a lot of the odd tools.

Hopefully I'll know more on it by the end of the weekend. Plan on trying to fix the condensation drain/clog and that sunday.


Not sure how to test for the vacuum lines being an issue but it does come out the vents and has variable speeds I just don't think its strong as it should be. For the day I had working ac in my old jeep (1998) the ac was strong from what I can remember but it had the factor blower motor, I am not sure if the one installed is any worse or better than the factory one.

This one is fine if your in the front seats but anyone sitting in the back seats roast for a long time usually by the time the ac is cooling it down for them where ever I am going has arrived.


Ryan

dave1123

Okay, the blower has a "squirrel cage" impeller on it and it's difficult to tell just by looking at it which direction it's supposed to rotate. Basically, the air enters the middle and is slung out by centrifugal force. You can drop it out and try spinning it up to see if it's moving air in the right direction. You can try holding a cigarette over the center and see if the smoke gets sucked in or blown out. When I replaced mine, I dropped it out, powered it up, and checked it's direction before disconnecting the wires. Don't quote me, but I think it was clockwise. When I installed my new one, the red wire was power and black was ground to make it spin in the right direction. BTW, it was Chinese.