blown 87

Be aware that if yours had the old part number resistor and it is bad the only one you can get now is the new style which means you have to do a simple rewire at the harness end where it plugs into the resistor.
If you do not do the rewire, the only speed you will get is high and you will go looking for other problems that do not exist.

VehiGAZ

Thanks for the tip Greg! I see a different p/n for '89 and later models than for pre-'89 models. But on that note, the pic of the part in Step 4 of the Pirtle write-up looks completely different from the picture of the 1989+ part on 928intl.com...



VS.



Or am I looking at apples and oranges?

SeanR

You just have to take pin 8 out of the harness and tape it up. Then move pin 6 to pin 8's position.

Install the new pack and plug the harness in and see if it works w/o modifying it. If it does, great, if not, swap the pins and you will be good to go.

The last picture is what you will be getting.

z driver 88t

Your two pictures are the same part. Just one has the cage around it. I just did this job about a month ago - exact same problem. Works fine now. My 84 had the old resistor pack part number and when I ordered the resistor pack, the new part number came. They look almost identical, but the part numbers are in fact different. Some quick forum searching showed that the old part is out of production. You will need to do a very minor wire swap in the resistor plug that SeanR posted above to work with the new style resistor.

For you the main challenge may be reaching the resistor with the blower motor in place. My blower motor bearing was going bad as well, so I replaced both the blower motor and resistor pack. I'm not sure if I could have reached my hand into the area where the resistor pack is without removing the blower motor. Someone else will have to chime in on that. If you do have to remove the blower motor, its not too hard and there are some good writeups on John's page for that too.

Bill Ball

The older style resistor pack had a fiber material cover. Newer one is plated metal. 89 uses the newer style and no re-wiring is needed.

VehiGAZ

Ok, I got ya. Thanks for the info, guys!

I will check the wiring to the control head tonight. If that isn't the problem, then I will pull the resistor tonight to check the part number and order a new one. I have another order to put in anyway for all the broken and missing bits I found when removing the interior.

z driver 88t

Interesting. There must have been some mid-model changes. My '84 had the old part number but I'm 99% positive it had a metal cage. First glance was that the two parts were identical and I thought they just updated the part number (Nissan does that a lot), but when I plugged in the new resistor pack and it wouldn't work, I SEARCHED on Rennlist and found the writeup on modifying the plug.

VehiGAZ

I now have some breathing room to get this fixed - my mech just called and needs me to wait until Monday to bring my car in for the R12 revert & rear A/C fix. I told him about fixing the rear blower motor but that I ran into this new problem and he just laughed and said, "It's a good thing you love that car, George!"

Damn good thing!

VehiGAZ

I went digging around in plenum by the firewall to see what was going on with the resistor pack - and discovered an old mouse-house right next to the evaporator... a pile of choice bedding materials (insulation mostly) taken from different parts of the car. I knew they were in there somewhere a couple of years ago, but I didn't know exactly where.

So I vacuumed it all out, and vacuumed around the resistor pack, and tried it again. All fan speeds worked again, even after flipping the A/C and read blower on and off a few times. Yay!

Hope it lasts - but I now know how to fix it if it doesn't.

So here's a new question... Where does the blower suck air in from? I felt around as much as I could, but it's a tight fit in there for sure. I'd really like to cover the air intake for the blower with some wire mesh so I don't get mice in there again.

Anyone know where the intake is and what I have to do to get to it?

WallyP

The retangular inlet above the blower.

VehiGAZ

I did not see this inlet. Where in this picture would it be?

Leon Speed

Look at the Pirtle page again where the picture is from. The blower sucks air through the air box, which is opened of closed to outside air through the actuator. When open to outside air, I'm guessing Whally means air comes in through the inlet to the left of the blower - in the corner where the mesh is.

Leon Speed

Ps. on the right side of the car there's also an opening, which, when it really really pours down with rain, make you ankle wet

VehiGAZ

I may be a bit confused Aryan... I want to know which way does fresh air get sucked into the blower housing itself? That inlet is likely how the mice got into the plenum.

So did you mean that the inlet I am looking for is somewhere in this area?

Mrmerlin

if you follow the arrow the opening for the blower box is at the bottom of the well that it is sitting in,
get a drop light and shine it down the well,
you will see where all of the leaves and other stuff is ,
the opening faces to the front of the car and its just about directly behind the well drain flap.
Now if it is filled with debris now is a good time to drop the blower box and take out the fan motor, and replace the inside/ outside air flap pod.

If you do drop the blower box .
First disconnect the battery,
then drop the CE panel,
Then put a towel over the CE panel to catch all the junk that will fall out the hole with the blower box.
Disconnect the 3 bolts for the blower motor (1 inside and 2 outside the car),
drop the blower box then the motor can also be worked through the blower box hole.
Re seal the blower box seal with 3M strip caulk, (found at the body shop supply).
Swap out the pod on the blower box,
Then clean the well out ,
Clean the blower motor housing and spray some brake cleaner into the motor bearings after first blowing out the motor with compressed air,
(do this outside as there will be a lot of airborne dust)
spray the bearings then blow them out do this a few times this will rinse out the dirt,
then with some lite oil lube the bearings also inspect the brushes and armature for wear.
Clean out the evaporator as its easier with the motor out.
Then refit motor to its position,
then lift the blower box into position,
then the CE panel