4x4 and Blower problems... vacuum issue?

[SLAVAGE]

I have a 91 Loyale wagon (5speed, push button 4wd, EA82 SPFI), and a few days ago it started making a grinding noise that gets worse with rotational speed, so at freeway speeds it almost sounds like a helicopter taking off.  I assumed it was another axle blow-out, as I've gone through 3 of them this summer and this one had a cracked boot for the last thousand or so miles, so I replaced the culprit axle (this time with an axle from MWE). 

 

However, the noise did not go away.  The next day it rained/snowed/iced and when I went to pop it into 4x4, nothing happened.  4x4 had been working great the previous week (before the sound came).  It also makes some sense now that the sound seems like it is coming from the rear - could it be the rear differential constantly trying to engage and grinding a bit?

 

Today I also realized that my heater is only blowing out of the dash no matter what setting its on, no defrost vents, no floor vents.  So that leads me to believe that I'm looking at a vaccum system issue.  My main question is: Is the 4x4 engagement on my car vaccum controlled, so are these two problems stemming from the same source?

 

Am I on the right track with the vaccum system?  And where would you start on troubleshooting the system?

 

Thanks

Edited December 6, 2013 by SLAVAGE

[SmashedGlass]

Vacuum for the climate control, yes: start by checking the vacuum line in the engine bay that T's near the intake and runs over behind the passenger strut tower.

Possibly also the cause for no 4x4, as I believe your single-range push button 4WD is controlled via vacuum? 

 

The grinding in the rear that gets louder with speed, is likely bad bearings. Though it's rare for the rear bearings to go on the L.

Edited December 6, 2013 by SmashedGlass

[SLAVAGE]

Went out and had a look, and indeed the vac supply line is disconnected.  It is connected to the canister up by the passenger strut and hanging loose at the other end.  But where do i hook it onto?  There's a spot near the intake?  And do I need any grease/oil on it to get a good seal when i hook it back up?

[SmashedGlass]

there should be a "T" somewhere near the throttle body with two other lines on it, above the right side cylinder head area; it'll be obvious by it's lack of the third hose and an open nipple. Should not require any greasing other than some spit, if it just falls off with no tugging then just cut a little bit of the end of the hose off to get to some less stretched material.

 

I'll post you a picture in the morning if you need it.

Edited December 6, 2013 by SmashedGlass

[SLAVAGE]

Found the vac connection, got my 4x4 and defrost back!  The noise is still there, the rear passenger wheel was sitting pretty wonky, so I jacked it up back there and the wheel had an insane amount of play, beyond what I've ever seen from a bad wheel bearing.  Took the wheel, castle nut, washers and the drum off, and found a ton of metal dust and the stub shaft splines look overly worn and there appears to be no axle cup anymore (not sure that is the correct thing to call it - I mean the part that has the female splines that the axle engages).  Bearings might be shot, not really sure here.

 

Gonna take it in to a shop tomorrow, its below zero here and I can't deal with this in the cold right now.

 

Thanks for your help SmashedGlass, you were right about the T for the vac connection being obvious - once I was looking in the right area of course!

[SmashedGlass]

That sounds like destroyed bearings to me. And you might as well get a new axle and all the other components.

[ivans imports]

Check vacume supply tp vacume storage tank were line comes off engine

[MilesFox]

Or the hub is stripping out from loose axle nut, or the washer are installed incorrectly. The flat washer is actually a spring washer, and has a dome shape where the conave side meets the hub, and the convex side meets the nut, which makes it hod torque.

[SLAVAGE]

So here's the saga of the passenger side rear wheel noise...

 

Took the Loyale into the shop, they replaced the drum and repacked the bearings, said the bearings were ok.  No noise for about a day and then it stated grinding again and would pop on hard left turns (when force was put over that wheel).  Drove it a few more days and took it back in as grinding and popping got worse and worse.

 

Established that the axle splines were worn down so much that they were causing the splines on the drum to strip, so found a guy on craigslist that was parting out an old loyale and I got the original axle and the drum from that.  I thought they were going to put in a warranty drum from the first repair but there was a miscommunication in the shop and they put in the used drum, with the axle and replaced the bearings this time too.  As soon as i left I noticed a rubbing sound when braking and turning left.  Not as bad as the grinding from before, so I chalked it up to the rust on the used drum needing a day to wear in.  Gave it two days and it got a little worse and then all of a sudden went away.

 

I took it back to the shop again and had them put on the new warranty drum that they were originally going to use.  They told me that they thought the continued noise could have been that the bearings didnt get pressed in perfectly straight when they installed them and had to work their way in.  I finally thought I had the winning combination: new drum + used OEM axle + new bearings, but the noise is back after only one day away, again its a metal on metal rubbing sound, not too harsh of grinding, and only during left turns and a sometimes during braking.

 

Any ideas on what to do?  I could check the washer as MilesFox suggests, but i dont have a torque wrench to properly torque the castle nut back on.  Is it good enough to just torque it as hard as I can with a breaker bar?  And can the spring washer wear out to the point wear its not providing any spring force anymore?

[djellum]

the nut can be tighter than spec without any real problems.  some people really torque them hard, but id make sure to go at least 140ish pounds since thats what the spec is.  the nut pushes on the spring washer which pushes a conical split ring into the drum.  pull the assembly apart and make sure that both the conical split ring and the concave area it fits in are smooth and have no ridges.  its common for people to put back old cone washers with groves worn into the top half even though you are supposed to replace them when you replace the axle. Im willing to bet you will find a lip worn into the conical split ring that prevents it from pushing fully into the drum.  also check that the spring washer is the proper one and the proper orientation.  it will have the word "out" stamped into it.

 

the subaru part listing is "center piece axle".  I believe its actually in the spec to replace them whenever you replace the axle, so you may be able to get a warranty out of the next repair if you find that they didn't do that. 

[MilesFox]

Go back to the guy with the loyale parts and salvage the trailing arm, swap the whole unit, bearing, washers and all