I just bought a 97 Outback that overheats so that I could swipe the tranny out of it and put it in my SVX.  I would like to fix the overheating and either use or sell the motor though.  

 

It overheats after about 10-15 minutes of driving.  No signs of head gasket issues.  No blockage in the heater core.  Pulled the t-stat.  Doesn't seem to be losing fluid anywhere.  With it running, I notice that the hose between the water pump and bottom of the radiator feels really spongy like there is no pressure in there, again with no stat.  It is hot, but spongy.  Is that a sign of no water pump flow?  Or should I look elsewhere.  I haven't got it to overheat or the fans to come on revving it to temp at 2000-2500 rpms.

 

I don't have a trip permit yet, so driving it enough to get it to overheat is not an option yet.

 

Any thoughts about the spongy hose?

it's the headgaskets.  (which can cause no coolant flow)

 

clogged radiator

radiator cap

fans

Not to rain on your parade, but an Outback transmission for an SVX? Really?  The only ones known to be a direct swap were out of the turbo Legacys.  They are also the only ones capable of handling the torque.

 

Did you match the gear ratio?  SVX were either 3.9 or the optional 3.545.  The torque converters are different as well.  A '97 Outback should have a 4.44 auto transmission. 

I think you have bigger problems than whether an engine you don't want is overheating.

Not to rain on your parade, but an Outback transmission for an SVX? Really?  The only ones known to be a direct swap were out of the turbo Legacys.  They are also the only ones capable of handling the torque.

 

Did you match the gear ratio?  SVX were either 3.9 or the optional 3.545.  The torque converters are different as well.  A '97 Outback should have a 4.44 auto transmission. 

I think you have bigger problems than whether an engine you don't want is overheating.

Don't worry, I have an umbrella. This is my sixth SVX and I've done 4.44s before, as have 100 others on subaru-svx.net. We even have a computer guru over there who rewrites the TCU to take different ratios and boost low-rpm line pressure and more. While the 3.90 and 4.11 trannys have not held up well to the EG33, the 4.44s have done just fine. They may not have the extra clutch packs, but the ratio helps keep the tranny "out of its own way". We get a lot of broken front diffs on the stock SVX 3.545 ratio.

 

But my question was about the water pump.

 

Thanks for the reply Gary. I'll check those three lower items tonight before jumping into the head gaskets. I've had many failed Subaru HGs in the past, and each time it was obvious. I'm sure my radiator cap needs replaced. I don't need to push down on it at all to turn it. And I have yet to verify that the fans come on, other than forcing them on with the AC. If I decide to sell the motor, I will probably replace the HGs anyway just 'cause.

I put my SVX radiator cap on there and it fit much more snugly.  So I ran it for awhile in my driveway and got it up to temp and the sponginess in the bottom radiator hose immediately went away.  I revved it up to get the driver side fan to come on and it did.  So I bit the bullet and drove it around for about 20 mins and the needle never moved.  I've read it many times, but I never thought a radiator cap could make that much difference.  WOW!  When does ever turn out to be the cheapest thing???

Classic description of symptoms of a blown head gasket on the 97 model 2.5 motor. Both my 98 and 99 Outbacks with the same motor blew their head gaskets in similar fashion.  

Every head gasket issue I've had has been accompanied by white smoke out the exhaust, disappearing coolant, oil mixed with coolant, and/or exhaust pressurizing the coolant system. I don't have any of those issues this time. And now I don't even have overheating.

Sounds like you got lucky. If I were you, I'd try and get a compression test for that motor. Or they can test the coolant for exhaust gasses. Having that peace of mind would be great just to be sure.

 

Are you still pulling the motor on this one? Could be one of the simplest fix and flips since it sounds like you've got a complete and good running car now. A shame to cannibalize a perfectly good Outback.

Every head gasket issue I've had has been accompanied by white smoke out the exhaust, disappearing coolant, oil mixed with coolant, and/or exhaust pressurizing the coolant system. I don't have any of those issues this time. And now I don't even have overheating.

Bad head gaskets show up in Subarus as over heating. When a HG breaks, exhaust gas pushes into the cooling system to cause the over heating. So yes, the exhaust will pressurize the coolant system, and can cause the radiator to start leaking. For what ever reason Subarus don't send white smoke (steam) out the tail pipe, or mix coolant with the oil, that shows up looking like chocolate milk shake on the oil dip stick. It is always that darn over heating problem with blown Subie HGs.

Sounds like you got lucky. If I were you, I'd try and get a compression test for that motor. Or they can test the coolant for exhaust gasses. Having that peace of mind would be great just to be sure.

 

Are you still pulling the motor on this one? Could be one of the simplest fix and flips since it sounds like you've got a complete and good running car now. A shame to cannibalize a perfectly good Outback.

Actually, I wouldn't call it a perfectly good outback. It has a wasted fender on it, the rear hatch has a big dent, clear coat is peeling all over, and there is at least one rear wheel bearing howling. Interior is so-so. And then there's the hole where the tranny is supposed to be. At least it has low miles. Only 157k.

Edited March 18, 201511 yr by redXTwedgie

For what ever reason Subarus don't send white smoke (steam) out the tail pipe, or mix coolant with the oil, that shows up looking like chocolate milk shake on the oil dip stick.

The last three Suby HG repairs I've done were because of bubbling reservoir/disappearing coolant, chocolate milk in the crank case, and thick white smoke out the exhaust.

 

Apparently, they don't all overheat because because of HGs. There are a number of components that can cause it. Like Gary started to list.

 

Like I said, I'm still probably going to change HGs anyway just to make it easier to sell, assuming I sell it.