LSD install in the 1041; A/C hose conundrum solved
Well I've been damn busy with expanded responsibility at work.... but finally got an evening to grind out some of the punch list items on the 940.
As I reported previously, I bought an DANA Power-LOK from Billy780 awhile back..... I was thinking about a TRUE-TRAC 588, but when this OE LSD came available from a 91 740, I bought it. Hopefully having an AW71 will protect those cross shafts.... only time will tell.
What I noticed when I pulled the LSD from the donor rear end, was
it had some serious preload on the carrier bearings. Compared to the G80s I've pulled, this unit was really "in there". The green books state that carrier preload is between .006" and .008". I think these units must have been set at .008" because you had to leverage it out of the 1041 housing. I recall that Simon Babbs found the same thing on a couple of these that he harvested.
I targeted the .008" preload, and found with the proper bearings/shims installed I was unable to convince the unit (with greased carrier cones and dead blow hammer) to get it into position. I did some JEEP forum searching, and found much data stating the Dana 30 (which our cars share with certain Jeeps) are recommended to use a case spreader for differential install. I found a simple design on YouTube built by a Jeep lover up in Canada, and basically followed his design with a couple tweaks.
Here you can see the case spreader that I built from 1/2" x 3" steel plate, and some 5/8" B7 hardened threaded rod:
With the spreader installed to the four points shown (but floating, not tightly bound to the housing.... 1/4 turn back from snug) I installed my indicator:
With the target of .008" spread, and an absolute limit of .015" which per DANA will deform the housing, I symmetrically opened the case:
Once achieved, and the "proper carrier shims installed"
(which took multiple attempts), the LSD dropped into place. The 1041 carrier caps (match marked.... don't mix them up!) were torqued into place at 45 lb.ft. of torque.
Done properly, the backlash must be confirmed unless you want to listen the rearend sing as you drive. OE specs are .005" to .007" per the green book (and a smidgen tighter per a 960 document I found online)...... I got mine to average .0065" and called it good! Here is the backlash checking:
I spent last Saturday wrestling the rear end assy. back into position.... something much easier done with 2 people, but I got it solo. For TB posterity, here are my rear dampers and B&G Sedan rear springs:
I just ordered some GM limited slip friction additive.... 4 oz. is what is needed, along with about 1.6L of gear lube of your choice. I stayed with Dino gear oil..... as that is what these rear ends were designed for. Others claim the synthetics work just fine with these clutch differentials.... but I heeded the advice of Tom from "Tom's Differentials", a subject matter expert.
NOW with the 1041 back between the frame rails, I worked to finally complete the A/C reconstruction. With some details covered earlier, I basically bought a new compressor, condenser, hose sets, and variable orifice tube (for improved low RPM cooling). One item that bit me HARD in the bum was the suction line. I had a hole worn thru mine from a clamp, and had to replace the original. This didn't go well.....being a thrifty guy, I bought a China replacement from Four Seasons..... and it didn't fit worth a damn. I actually broke the hex nut at the low side attachment port on the compressor.....trying to use the wrench leverage to "walk it on"
Undeterred, I bought another one ($35, almost throw away priced).... and then spent another evening bending & massaging the damn thing to try and get fitment. I finally planted the SURRENDER flag on the second one
after another fruitless evening.
What to do? Posted in wanted for a used OEM.... none turned up. Out of near desperation, I contacted a local Volvo parts shop called VOLUPARTS, and told them of the conundrum. Their response was simple:
92 940 A C hose Low pressure 91-92 only 940 USE # 1348538 instead of 3537731 ; 1373532; 3537901; 3522681
I looked over the webstore 3D illustrations, which are quite misleading. After an exchange of emails, Bill Eidson from VOLUPARTS said "stop overthinking this, it works!" Why not, I thought, and ordered.
Well tonight I installed their recommendation..... and it fits like a dream:
The damn thing works great! This P/N was stock on an 86-90 740, and the 780s, I believe.
As Homer Simpson once said.... "There is a time to think, and a time to act". I'm glad I listened to Bill, and plunked down my credit card. As of tonight, the complete A/C system is reinstalled, with POE ester oil installed in all the right places and volumes. Soon I'll bust out the deep vac pump and evacuate the system to confirm she's leak free.
)
. Read from your meter to the battery NEG post when installed.... if resistance isn't near nothing, your ground is NGC (no good condition).
I've got to drive this thing until I retire to break even!
