long travel Outbacks or making Subarus faster and more reliable offroad

[el_freddo]

Awesome pics and trip report as usual Todd. I reckon my favourite pic is the one you walked in for - with the two big rocky outcrops that made a saddle and the sunset in the background; the vegetation on either side of the pic give us a nice amount of colour to balance it out. Mint! 

Cheers 

Bennie

[pontoontodd]

I made a walkaround video of the black Outback and recently revised it with some suggestions from slammo.

 

Edited May 2 by pontoontodd

[pontoontodd]

B and I did some work on our cars.  Replaced a front CV axle in the Forester that's been making noise occasionally but for quite a while.  B changed his engine and trans oils.

Trying to figure out Impreza's potential cooling problems.  Seems better with the new thermostat but still crept up a couple times on our last trip out west in mild ambient temps.  Really need to get some temp senders calibrated to the Haltech and get them installed on top and bottom of radiator.  IIRC the middle of the coolant temp gauge is about 210F on the Haltech but I can't guarantee either is accurate.  Infrared temp gun near the coolant temp sensor indicates it's at least close.  Then 3/4 of the way up the gauge is 217F at the Haltech, probably still nothing to worry about but should confirm actual temps.  Also thermostat is at the bottom/inlet of engine while the temp sensor is at the top so I'm getting coolant temp readings from the opposite end of the system than where the temps are controlled.  One thing we did was a smoke test on three different Subarus.  The Impreza's fans seemed to suck in the smoke as well as my white Outback with the stock fans.  Could see at least some of it blowing out the back of the radiator, didn't seem to be blowing around the sides or out from between the condenser and radiator.  So I think the fans are at least decent but since the overheating is a low vehicle speed issue perhaps we could get better fans although these had the highest CFM rating of any fans I could find.  One idea I have is to add a large heater core above the ABS unit under the hood vent on the passenger side with an electric fan on it.  The one we added to the back of the black Outback dropped coolant temps by 20F so that should do the trick and would be fairly easy to add.

AC was discharged before our last trip so I added some refrigerant but now it will cycle on and off about once a minute.  The high side spikes up to about 250psi while the low side drops to 20psi, then they briefly start to converge before the compressor kicks off.  Wondering if I have a clogged orifice as this seems like a much larger pressure difference than the charts show.

One time out west the coolant temps went up the power steering pump stopped working at low RPMs.  After we got home I first tried installing a pump from an EZ30.  Bracket is slightly different, no big deal, I'll swap the bracket.  Nope, pulley is a different size too, not going to mess with trying to swap that over.  So much for Legos.  Got an EZ36 PS pump from a local junkyard and swapped it in this morning which solved that issue. 

We decided to tack up a couple trailing arms for B's eventual billet rear knuckle swap.

Also trying to figure out my gas tank filling issue on the Impreza.  I replaced the carbon canister which is usually the culprit.  Not much better, also the one I pulled out seems good (not dumping carbon pellets out like the bad ones usually do).  Pulled the hose off the canister that goes to the gas tank vent.  When we blow compressed air in the gas filler air comes out that tube (seemed maybe a little blocked at first) similar to the Forester's.  Last time I went to fill up with gas it shut off before the tank was full, I pulled that hose off the canister and then the tank filled as it should.  Next time I'll try to remember to pull the other large hose off the canister instead.

Edited April 27 by pontoontodd

[slammo]

I agree, water temp sensors will tell you if it's an airflow problem. You could try removing the hood scoop and vent inserts in the hood, give all that air from the fans somewhere to go

[pontoontodd]

B and I got a few things done on my cars.

Our main focus was solving the axle issue in the 2002 Outback and I think we accomplished that.

The axle in place was definitely getting overextended and the worst case for that is slightly above ride height, so not surprising that it was more of a problem when the car was overloaded.

We measured a bunch of axles.  Unfortunately it took us a bit to realize/remember that the axles for the press in rear wheel bearings in the strut cars are a slightly different spline than the bolt in wheel bearings in the multilink cars.  Again, so much for Legos.  Of course most of the axles we have are for the strut cars.  The axle that had been in the right rear measures in between the pair I recently got from a junkyard.  So it might be slightly shorter than the one it had replaced which might have been the main problem.  Any of them would have probably been too short at the most extended position.  I added a 1/4" thick spacer between the axle and the wheel bearing.  With that in place there's a millimeter or two of plunge travel left at the most extended position but it will still go to full droop and be close to the limit of bottoming out the inner CV.  I vaguely recall making a thin spacer years ago but there wasn't one in place when we've taken it apart.  To still get a decent crimp on the axle nut with the spacer I modified it in the lathe.

A contributing factor might be that we replaced the rear diff bushings the last time we replaced the axle so the diff can't move around as much now.

Also changed the oil and filter and tweaked the alignment a bit.

Haven't put a ton of miles on it but drove it around town quite a bit today and definitely used most of the travel, seems good so far.  Definitely would have popped out by now with the old assembly.

 

Next we worked on my green Impreza, changed oil and tweaked the alignment on that.  

Main project there was the AC.  To recap, last summer it worked fine.  A couple months ago it had no (low?) charge so I charged it up.  Seemed to have much higher pressure differential than it should, would get up to about 20psi low 250psi high and shut off, pressures would converge, it would turn back on, and would continue doing that every minute or so.  Assumed the orifice was clogged.

Replaced the orifice and drier/filter too while we were at it.  Pulled a vacuum, got down to about 20"Hg and seemed to hold that with the vacuum pump off.  Put about half of a 12oz can of R134a in, runs at about 4psi on the low side and 90psi on the high side.  So it still seems like there is some kind of blockage.  Might try to backflush the condenser and evaporator, not sure what else to try at this point.

Got a couple temp sensors that should have good calibrations for the Haltech.  Plan to install those at both ends of the cooling system.  Also plan to find that large heater core and small electric fan we had in the back of the black Outback and install that under the hood of the green Impreza under the passenger side hood vent.  At the same time will probably add shutoff valves so we can bypass the in dash heater core to see if that helps cool down the cabin in the summer.

Edited May 7 by pontoontodd

[pontoontodd]

One of my friends said a good rule of thumb for R134a is that the pressure on both sides after the system has sat for a while should be about 5-10psi more than the ambient temp in Fahrenheit.  Seems weird but also seems to check out.  I added some with the AC off but it would only get up to about 65psi (both sides).  When I turned the AC back on the high and low pressures had gone up a bit.  After a minute or so of running it would shut off for a bit, pressures would start to equalize, then it would kick back in.  I slowly kept adding more (to the low side) with the AC on until it stopped cycling on and off.  Wound up adding most of a second can, probably has somewhere around the 19-23oz total it's supposed to have.  Low side is now about 30psi, high side about 150psi, blows cold.  Drove around town quite a bit today, never noticed the AC cycling on and off, cold the whole time.

The temp gauge did spike up to about 3/4 one time I started driving but then went back down slightly below the middle where it stayed for the rest of the time.  Definitely need to get some accurate temp sensors installed.

Edited Wednesday at 07:53 PM by pontoontodd

[pontoontodd]

B replaced some bushings and ball joints on the front end of his white Forester.

He also blew some dust out of the air filter on my Impreza.  Messed with the rear seat belts too, they seem to just lock up sometimes.  He found that after pushing the belt back into the reel all the way they then work normally.  One problem is there's just more friction now with the belt rerouting.  Not a huge deal as the rear seat is rarely occupied.

The main thing I worked on was mounting the full size Dodge van heater core and 8" electric fan under the passenger side hood vent.  B also pointed out there is room for about a 10" puller fan behind the driver's side of the radiator.

Fan lines up nicely with the hood vent.

Need to paint those brackets.  I might get some valves so I can bypass either the heater core in the summer or this one in the winter before I bother plumbing it in.  If anyone knows of any good selectable tees with the right size barb fitting on them I'm looking for one.  The only tees I've found are fairly expensive and threaded so then I'd have to get barb fittings too.  I could get one or two of these:

https://www.oldairproducts.com/product/25-1018-bypass-heater-valve

https://www.rockauto.com/en/moreinfo.php?pk=10849736&cc=1028012&pt=6860&jsn=647&_nck=Hsaep13M915uuutk8%2Bf0wOeyqERYmFnnScHREpb2kaeQZMBwbsjIzbH8p6X7b8doV7ZhIKZrju0iMu8H6dXM7%2Brn6x%2B0jcKSODBkngSksRc8Zan%2B8zelEqDy3fSWbwfOPltq76G%2F%2BqudM5QnqkfncwVTbvl7WYgy%2FB5R5n7ZhrV7LBZsioiB3TmAKe3DAh41KLIKq6Sxllk%2FuLl9WzsOYRw%2BOcEcAfTSJlHRiVNIl1RPrA%2FNoewztrWsDKuoD6xe7CNXcLhVSC%2FH96c%2B3QTLRwUrVp4D8yNkgd0OuL1jSrQILgJitIgI5w%3D%3D

[el_freddo]

The VT commodore had a vacuum actuated tap from memory. That might work ok. 

https://www.ebay.com.au/itm/401549783595?_skw=corvette+heater+tap&itmmeta=01JV1WVEBGSPBTEP9B9113TB8G&hash=item5d7e3b722b:g:OnkAAeSwpRRoGwiv&itmprp=enc%3AAQAKAAAA8FkggFvd1GGDu0w3yXCmi1eJINj5jgQt19ervaLpB6mTJVlbBUu4vglR9vmIgxvxhRqvEnQJ9doxy%2BZktYtxQqsZbJrKIht9otsWH84id9755%2BIn4cypkZl27%2FKDjPv%2BOsNEZ56AEsLRJhfG4c2ur2ajr7zjHFcU5JxN%2FWNrtoG2K1ptrcQU37fJiCbGw0K2Fo8C6CPpRgnrpt0Z5HDKMS%2FsRHx7x2D1HmCQYm5cwboEgRKEm%2FAyJisAIvLqnBIPF9%2FBi%2FMeZ4G5Ee8S1CnZI%2Bp21AmT9uMJ3RwDd4tUUigpFT6ya35g5u%2B4YLFI1ivSog%3D%3D|tkp%3ABFBM8uXtvNhl

Or if you can find one from a Brat era EA81 they have a cable operated tap that’s a bypass setup rather than just a tap. 

There’s this one that popped up in my search for something else. It’s like the best setup but vacuum operated much like the VT unit, except it’s a bypass:

https://www.ebay.com.au/itm/113243302295?_skw=corvette+heater+tap&itmmeta=01JV1WVEBGGHWS4HTZR14X1VKH&hash=item1a5dd3a997:g:WhcAAOSwDMNkGQe4&itmprp=enc%3AAQAKAAAA8FkggFvd1GGDu0w3yXCmi1eL7rKl%2F2ljcIXVOOnL54JOwJ%2BUR2fbUufq%2FoaM9p7nLt85Zdd7srrSorj2BIUWgGYmb4Flk3R2uJRBAkQEtJbW%2FWyIGJoKk5hAQAJ15GBRPSVynDiwwJynUYCg83YGr%2BVPLXw3%2B7y1dsD%2BgxvfWL1RMtnFO9t0ly%2BeOt6vf2XdZjwrywR65%2BQRM6AVvBIzW6CMz8caCR3ZoI%2BBQFqFxb%2BFGy%2BT5X7AQDUVNFYSSZWq%2FU9FNhnNNkFfbK1C0qWh7oYEypRNfLV%2F2X8DJCDQK7jboTUHKNl1yQIRfpYTUXyJCQ%3D%3D|tkp%3ABFBM8uXtvNhl

Damn I hate these eBay link addresses! 

Cheers 

Bennie

[azdave]

On 5/7/2025 at 12:51 PM, pontoontodd said:

One of my friends said a good rule of thumb for R134a is that the pressure on both sides after the system has sat for a while should be about 5-10psi more than the ambient temp in Fahrenheit. 

 

That is only true in a narrow range of ambient temperatures. For you to have read 65 PSI (assuming there was at least enough gas in the system to reach the saturation point) I'm guessing it was about 66F outside at the time you measured the inactive system pressure. You can find online gas/temp charts that show the relationship and values.

Adding gas the way you did is a great way to sneak up on the proper fill if you don't know how much was in the system to begin with but don't be temped to "add just a little more". The compressor will cycle on and off for three reasons. Low gas charge, evaporator coil  too cold or system overcharge. A compressor cycling because the evap coil temp is too low is the only time it is acceptable to routinely cycle. Cycling due to a low charge is not good because the refrigerant also carries the lubrication oil that the pump needs and an overcharge will wear out your pump and blow hoses.

I fill my systems by monitoring the evap coil return line temperature too. When I know I am close to the proper fill, I watch the temp of the fat line leaving the evap coil. You put in a little gas and watch to see if the outlet line drops a few degrees accordingly. You do that a few times as long as the temps keep dropping a  little each time. Once you add a little gas and the temp stops dropping, you know you have reached the point that the evap coil cannot boil off any further addition of refrigerant. It's a more nerdy way to do it but I'm in the SW desert and I need my cooling when it is 110 outside. I daily drive my 87 to work each day and driving home in the afternoon on the freeway really loads the system.

Your low 30, high 150 readings sound about right for a properly charged system on a day that was in the 70's but you don't mention the ambient temps on the day you did the work. Sounds like you have it dialed in pretty well. 

Speaking of R134a, a local farm store had 16oz cans of R134 for $5 a can this weekend. I stocked up for sure.

 

[pontoontodd]

16 hours ago, el_freddo said:

The VT commodore had a vacuum actuated tap from memory. That might work ok. 

https://www.ebay.com.au/itm/401549783595?_skw=corvette+heater+tap&itmmeta=01JV1WVEBGSPBTEP9B9113TB8G&hash=item5d7e3b722b:g:OnkAAeSwpRRoGwiv&itmprp=enc%3AAQAKAAAA8FkggFvd1GGDu0w3yXCmi1eJINj5jgQt19ervaLpB6mTJVlbBUu4vglR9vmIgxvxhRqvEnQJ9doxy%2BZktYtxQqsZbJrKIht9otsWH84id9755%2BIn4cypkZl27%2FKDjPv%2BOsNEZ56AEsLRJhfG4c2ur2ajr7zjHFcU5JxN%2FWNrtoG2K1ptrcQU37fJiCbGw0K2Fo8C6CPpRgnrpt0Z5HDKMS%2FsRHx7x2D1HmCQYm5cwboEgRKEm%2FAyJisAIvLqnBIPF9%2FBi%2FMeZ4G5Ee8S1CnZI%2Bp21AmT9uMJ3RwDd4tUUigpFT6ya35g5u%2B4YLFI1ivSog%3D%3D|tkp%3ABFBM8uXtvNhl

Or if you can find one from a Brat era EA81 they have a cable operated tap that’s a bypass setup rather than just a tap. 

There’s this one that popped up in my search for something else. It’s like the best setup but vacuum operated much like the VT unit, except it’s a bypass:

https://www.ebay.com.au/itm/113243302295?_skw=corvette+heater+tap&itmmeta=01JV1WVEBGGHWS4HTZR14X1VKH&hash=item1a5dd3a997:g:WhcAAOSwDMNkGQe4&itmprp=enc%3AAQAKAAAA8FkggFvd1GGDu0w3yXCmi1eL7rKl%2F2ljcIXVOOnL54JOwJ%2BUR2fbUufq%2FoaM9p7nLt85Zdd7srrSorj2BIUWgGYmb4Flk3R2uJRBAkQEtJbW%2FWyIGJoKk5hAQAJ15GBRPSVynDiwwJynUYCg83YGr%2BVPLXw3%2B7y1dsD%2BgxvfWL1RMtnFO9t0ly%2BeOt6vf2XdZjwrywR65%2BQRM6AVvBIzW6CMz8caCR3ZoI%2BBQFqFxb%2BFGy%2BT5X7AQDUVNFYSSZWq%2FU9FNhnNNkFfbK1C0qWh7oYEypRNfLV%2F2X8DJCDQK7jboTUHKNl1yQIRfpYTUXyJCQ%3D%3D|tkp%3ABFBM8uXtvNhl

Damn I hate these eBay link addresses! 

Cheers 

Bennie

Thanks for the links.  For the ebay addresses, you can just cut off everything after the item number (starting with and including the question mark).

Slammo found at least one other one similar to that Holden one you posted but after discussing it with him a bit more I probably won't bother with the bypass valves for now.  Make sure the extra heater core does its job and on cool mornings esp up north I still might want the heat from the stock heater core.  Plus it will just be simpler and fewer potential leaks.

It was 83F out today and while running the AC the temp gauge was up in the 3/4 range most of the time.  Would drop down with the AC off.  When I got home and it was at 3/4 on the temp gauge, I left the engine running and popped the hood and didn't see any boiling in the overflow.  I pointed the IR temp gun at a few things.  Upper water neck (where the sensor is located) was about 210F.  Radiator was around 200F top and bottom.  So probably nothing to really worry about.  Gotta get some accurate temp readings going.

[pontoontodd]

12 hours ago, azdave said:

 

That is only true in a narrow range of ambient temperatures. For you to have read 65 PSI (assuming there was at least enough gas in the system to reach the saturation point) I'm guessing it was about 66F outside at the time you measured the inactive system pressure. You can find online gas/temp charts that show the relationship and values.

Adding gas the way you did is a great way to sneak up on the proper fill if you don't know how much was in the system to begin with but don't be temped to "add just a little more". The compressor will cycle on and off for three reasons. Low gas charge, evaporator coil  too cold or system overcharge. A compressor cycling because the evap coil temp is too low is the only time it is acceptable to routinely cycle. Cycling due to a low charge is not good because the refrigerant also carries the lubrication oil that the pump needs and an overcharge will wear out your pump and blow hoses.

I fill my systems by monitoring the evap coil return line temperature too. When I know I am close to the proper fill, I watch the temp of the fat line leaving the evap coil. You put in a little gas and watch to see if the outlet line drops a few degrees accordingly. You do that a few times as long as the temps keep dropping a  little each time. Once you add a little gas and the temp stops dropping, you know you have reached the point that the evap coil cannot boil off any further addition of refrigerant. It's a more nerdy way to do it but I'm in the SW desert and I need my cooling when it is 110 outside. I daily drive my 87 to work each day and driving home in the afternoon on the freeway really loads the system.

Your low 30, high 150 readings sound about right for a properly charged system on a day that was in the 70's but you don't mention the ambient temps on the day you did the work. Sounds like you have it dialed in pretty well. 

Speaking of R134a, a local farm store had 16oz cans of R134 for $5 a can this weekend. I stocked up for sure.

 

Yeah, I think it's good now, been working well and not cycling on and off.  It was probably in the 70s when I finished charging it.  And not overcharged, I know as you say that can be hard on AC components.  Your AC definitely has to be top notch to be comfortable in AZ.  I like your technique of monitoring the AC line temp and stop filling when it stops dropping.  How do you measure that temp?

Dang $5/can is a killer deal.