I think the best way to accurately determine if a smaller alt. pulley is needed is, measure the voltage system with a volt meter when the fan is off, and when it is on @ idle. Then turn on all the accessories while the fan is on, @ idle. Then, swap pullies, and repeat.

 

True, but my main concern is the mechanical failure point of the alternator bearings at high rpm's

Currently the 1 7/8ths looks too dangerous at WOT, however the 2 1/4" and the 2" have some distinct possibility in normal operating range with very little chance of causing bearing failure at the higher rpm's...

 

Oh, got it. I guess we need to find out what the average failing point of the alt. bearings are, and calculate from there.

However, I have been running the HHR fan for a couple of weeks now, and have not noticed any irregular voltage situations (headlights on, at a stoplight with foot on brake, a/c running full blast, fan running @ 100%, radio on, with a turn signal blinking). I guess I should try it with my light bar fired up as well. OOHH!! Fun test for me tonight!! Get down!

 

Hey.. don't forget to turn on the wipers and beep your horn constantly while doing the test.

PS
I think the local jails are installing internet so you'll still be able to post up your findings after the ride....


Seriously though.. I'm interested to see what cha find out. I'm also runnin' a sub and amp, GPS, extra lighting, etc etc.

The output at idle and below 2000 rpm's is what I'm most concerned with.

 

Well, I looked into two. The first is a 180 amp.
http://cgi.ebay.com/ebaymotors/ws/eB...#ht_1257wt_921

The 2nd was the 04 Durango, 4.7L 160 amp
http://www.autozone.com/autozone/par...90_23521_4453_

 

Hey Blown (or anyone else thats done this), did you cut your shroud??


I never saw any trimmed up pics or install pics so I'll post my preliminary pics with the Derale controller unit...

Here's the controler I chose



Here's the beginning mounting of the controller...



Next is showing trim work
Red areas removed were for Radiator Hose clearance and the end tabs that won't be used just to clean up the install.
Green dots are where I drilled 7/64th" holes in the bracing for zip ties to secure the wires against the shroud...



I actually mounted the controler upside down just to bring the wires closer to the shroud. This will make no difference as the adjustment is a screw that is rotated up to 3/4 of a turn. its located behind the round rubber plug next to the relay


This is all the wires run and secured in place. Remeber your looking at the side that will face the engine bay



This is a final pic with the temp probe plugged in.


I shoud be installing this tomorrow (Saturday) I might have to trim a bit more by the upper radiator hose. Also I still have to make actual mounting brackets and side plates for the assembly.


Any input would be greatly appreciated...

 

I removed the shroud completely. Here is how I mounted mine.
Fan is hard mounted.

I used
Two M8(8mm) 1.25 X 45mm bolts.
Two 8mm Extruded U nuts.
Two small bolts with nuts/washers.

HHRFan2002.jpg

First we matched up the bolts threads form the OEM mount, marked the HHR fan and drilled holes for the extruded nuts. Then we drilled holls in the extruded nuts and mounted them to the HHR fan.
HHRFan2003.jpg
Then put the fan in place and bolted it up using the 8mm bolts going through the OEM mounts into the extruded nuts.

Here is the fan mounted.
HHRFan2004.jpg

 

I was refering to the HHR shroud... did you have to cut it for the upper radiator hose or did you must mount it off center?

In your pics it doesn't show that side of the HHR fan/shroud so thats what I was unsure of...

 

Nope, I didn't have to trim it at all. Its the exact same size as the radiator and will found up without modification.

 

OK...Guess I did some unnecessary preemptive trimming just for the fun of it.

-----------------------------------------------------------------------


So here's my detailed mount/install pics with the Derale controller.

First I decided I was going to use pieces of the stock fan shroud as my
mounts. Here's the two pieces I cut off and used.
Note: the top piece is boxed and I used the entire boxed piece to retain
rigidity of the assembley. The bottom pice was over cut so I could trim it to fit.


First I trimmed down the lower piece to fit inside the ribs of the HHR shroud.
I then taped it in place to do a test fit to ensure I had it in the proper
location before permanently affixing it to the shroud.


Once I got the location right, I used a plastic epoxy and 2 screws to permanently mount it.
Note: be sure to use SHORT screws so they don't touch the radiator when installed.


Full size pic of the lower tab installed on the shroud:



The upper mount was a bit trickier. I had to remove the ribs from the very
top of the HHR shroud so I could have a smooth mounting surface for the
original piece to be glued/riveted to. For the top piece I trimmed it down to
the exact "boxed" size of the original piece. To locate the proper mounting
position, I installed the fan with the lower tab and marked the position for
the upper mount. Once marked, I put it on the work bench and clamped it
in place (spring loaded clamps) Then I proceded to drill rivet holes, placing a
rivet in each one just to keep the holes lined up as I drilled the next one.
After all the holes were drilled I pulled the rivets, removed the clips, and
applied "goop" adhesive to both parts. I then let the parts dry for 5
minutes, then Pressed the parts together and clamed them in place. once
clamped in place I reinstalled the rivets (using a washer on the back side of
each rivet) and "riveted" them into place. This also helped clamp the glue
tighter to ensure a solid bond.



Here's the radiator side view of the upper mount.




Once dry (about an hour) I installed the fan and ran the wires. Also by
using the top mount, the factory trim piece can go back into its original
position with all 5 pop rivets for an extra clean look. (trim piece was not
installed in this pic)



Now for the wiring. The dreale box requres a switched power wire to turn
on the relay assembly (yellow wire) and has a green wire for A/C run mode.
Fuse #54 is a spare switched fuse and can be used for the yellow wire. The
A/C wire was a little harder to figure out. You can wire it directly to the A/C
relay on pin#87 (top right pin)



After install I tested the fan assembly and it performed flawlessly. the A/C
control worked as well as the temp probe in the upper radiator hose. I may
decide to make one or two more small tweaks to the turn on temp, but that
will probably be after I install my 180 thermostat.

Overall I'd say this is a great mod, it does free up a minute amount of
power, but more importantly it removes a reasonable amount of lag from the
motor which can be felt while driving.

The only down side I've noticed so far is the fan is almost TOO quiet, so its
hard to tell if its on while the truck is running.