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Troubleshooting cooling system help


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no question there are some reviews that are less-than-legit, but it's a datapoint even if not 100% reliable. Even car manufacturers shift sources. The Roki filters Subaru sold in the past were good. Then they changed to a supplier that had crimp joints that leaked.

 

moving targets......

Yeah, i've struggled with this in the past.  Once while job searching several years ago, I came across a job ad on Craig's List looking for people to write Yelp reviews.  I reported it to you Yelp's customer service email and got a reply back that basically said, "yeah, we know, we try to weed those out."  Kind of opened my eyes and reminded me not to believe everything I read on the internet.

 

That said, not ALL reviews are BS.  I try to look for language that any given review was written by a human giving their honest opinion on a product, but it can be tough to pick those out.

 

On the cooling issue,  exchanged the stat i got from Napa for a Wix one (thx for reminding me about that brand rocketman!) and I've ziptied the overflow tube and put some silicone around the tube where it enters the overflow tank.  The cap has a nice, positive click when closing so I'm calling that good.

 

Again, haven't driven it enough to know if any of those things made a difference.  But might not matter any way, looks like Rick (General Disorder) and I are going to do some horse-trading which will leave me with a rebuilt 2.5 and something neat for all the performance builder kids out there.

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I had a similar nagging cooling system problem with my 98 Forester (granted it had a 2.2 transplant so the head gasket problem was less likely.)  I did most of what you suggested without total success, but finally and completely licked the problem. (And I never did conclusively figure out what caused it in the first place--I just knew when it finally got fixed.) First I installed a 160 degree thermostat (a good parts man with a buyer's guide should be able to find one.)  I then removed the factory overflow tank and substituted a junk yard special Jeep Cherokee overflow tank which I mounted  on the front passenger side face of the firewall as high as possible.  I connected the small hose on the new overflow tank to the nipple on the radiator fill neck and I T'd using hardware store plastic pipe fittings and worm drive clamps the large hose from the new overflow tank into one of the heater hoses that run across above the transmission.  All of this requires a fair amount of tinkering, primarily because of the tight quarters. While I was in the vicinity, I eliminated the coolant feed and return for the throttle body by capping the nipples on the top of the engine. I made certain that the overflow tank cap could not hold any pressure by removing its pressure valve and gasket.  I also modified the radiator pressure cap so that its only function is to permanently close off the radiator filler neck but so that it also cannot hold pressure in the cooling system. You can do that by removing the little pressure-holding disk in the center bottom of the radiator cap and then installing the cap with a layer of RTV sealer to make it leak-proof--you won't remove it again, since coolant is added via the overflow tank.

 

 For over a year I've run the cooling system like this--no pressure anywhere in the system. I originally topped up the coolant by bringing the level up so that coolant just showed in the bottom of the reservoir when the engine was cold.  Without a sealed system, I've lost only a tiny amount of coolant to evaporation, but probably no more than a cupful in a year. In all kinds of weather, including very hot summer days with the A/C on, I've never seen the temperature anywhere near to overheating, I get adequate heat in the winter although this particular vehicle was always a little slow to heat up initially, and it still is.  Beyond all of the above benefits, any cooling system leaks that I may develop over time (either internal or external) now will be a non-pressurized dribble and not an explosive discharge which tends to blow hoses off, deplete coolant really rapidly, and/or cause big problems.

 

 It took a fair amount of experimentation to get all of these different changes figured out, but for me at least it has been worth all the aggravation of getting to this point so that I can have a vehicle that I can trust and which I don't feel that I have to check the coolant every day as I did before.

 

I also highly recommend the older 2.2 engine transplant, although the non-interference 2.2's probably are very scarce now.  Mine was a 93 from a  Legacy and was a pretty easy swap except for changing the sensors on the engine from the engine's OBD I sensors to the car's OBD II's. (Fortunately they all fit the engine correctly but the sensors and their wire terminations are different.)  I used the 2.5's intake manifold so all of the wiring for it simply got reused.  In my experience, they should have built Foresters this way from the factory. A bulletproof engine and a reliable cooling system made this vehicle about perfect from my vantage point!

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I had a similar nagging cooling system problem with my 98 Forester (granted it had a 2.2 transplant so the head gasket problem was less likely.)  I did most of what you suggested without total success, but finally and completely licked the problem. (And I never did conclusively figure out what caused it in the first place--I just knew when it finally got fixed.) First I installed a 160 degree thermostat (a good parts man with a buyer's guide should be able to find one.)  I then removed the factory overflow tank and substituted a junk yard special Jeep Cherokee overflow tank which I mounted  on the front passenger side face of the firewall as high as possible.  I connected the small hose on the new overflow tank to the nipple on the radiator fill neck and I T'd using hardware store plastic pipe fittings and worm drive clamps the large hose from the new overflow tank into one of the heater hoses that run across above the transmission.  All of this requires a fair amount of tinkering, primarily because of the tight quarters. While I was in the vicinity, I eliminated the coolant feed and return for the throttle body by capping the nipples on the top of the engine. I made certain that the overflow tank cap could not hold any pressure by removing its pressure valve and gasket.  I also modified the radiator pressure cap so that its only function is to permanently close off the radiator filler neck but so that it also cannot hold pressure in the cooling system. You can do that by removing the little pressure-holding disk in the center bottom of the radiator cap and then installing the cap with a layer of RTV sealer to make it leak-proof--you won't remove it again, since coolant is added via the overflow tank.

 

 For over a year I've run the cooling system like this--no pressure anywhere in the system. I originally topped up the coolant by bringing the level up so that coolant just showed in the bottom of the reservoir when the engine was cold.  Without a sealed system, I've lost only a tiny amount of coolant to evaporation, but probably no more than a cupful in a year. In all kinds of weather, including very hot summer days with the A/C on, I've never seen the temperature anywhere near to overheating, I get adequate heat in the winter although this particular vehicle was always a little slow to heat up initially, and it still is.  Beyond all of the above benefits, any cooling system leaks that I may develop over time (either internal or external) now will be a non-pressurized dribble and not an explosive discharge which tends to blow hoses off, deplete coolant really rapidly, and/or cause big problems.

 

 It took a fair amount of experimentation to get all of these different changes figured out, but for me at least it has been worth all the aggravation of getting to this point so that I can have a vehicle that I can trust and which I don't feel that I have to check the coolant every day as I did before.

 

I also highly recommend the older 2.2 engine transplant, although the non-interference 2.2's probably are very scarce now.  Mine was a 93 from a  Legacy and was a pretty easy swap except for changing the sensors on the engine from the engine's OBD I sensors to the car's OBD II's. (Fortunately they all fit the engine correctly but the sensors and their wire terminations are different.)  I used the 2.5's intake manifold so all of the wiring for it simply got reused.  In my experience, they should have built Foresters this way from the factory. A bulletproof engine and a reliable cooling system made this vehicle about perfect from my vantage point!

egads, that's quite the write up. I'm not getting too fancy with this.  If I break down, I break down, I get towed, i fix it.  Won't do a 2.2 swap, no need, the 2.5 single cam is a good engine if treated right and having driven both, I like the extra power of the 2.5.  I appreciate you taking the time to type all that out, and it's good info for the kids learning how to wrench, whether or not you're right, still some data for the database.  Part of why I love this board, I've learned tons here.

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I've done the no pressure cooling system mod to every vehicle I've owned and never had any problems with either coolant loss or overheating (or any other problems for that matter.)  This includes cars and trucks including several diesel trucks.  I've also done it to vehicles like Buick Century 3.8's which you might think would have been problematic as far as the temperature settings on the electric cooling fan.  I have usually run 180 degree thermostats when I've had to change them, but several of the vehicles ran out their lifetime with 192 degree 'stats with no problems, either.

 

Also, I certainly was not advocating all that I have done, but thought someone might see something in there that would be helpful in their situation.  I had to do all of this because I bought the car as a "builder" with a vague history and known problems from the outset.  I wouldn't have done the transplant initially if the car had had a good engine up front, but it didn't and I figured from what I'd read that for my purposes the 2.2 was an upgrade. It's got over 200K on it now and doesn't burn enough oil to detect in 3000 miles, leaks very little, and continues to run like a champ. If the rubber band breaks, I don't bend valves or hole pistons either. As you can detect, I'm a stubborn old goat and don't take kindly to being thwarted by a vehicle! 

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The only 2.2 that would fit his car is from a 99 to 01. And they aren't worth having. They have piston ring problems and typically burn copius amounts of oil - worse than the 2.5. The fix for that engine is to replace it with the 2.5.

 

The 2.5 has external headgasket weeping problems - fixed with the 770 turbo gaskets. Install new rings, knurled piston skirts, a 10mm oil pump and run synthetic oil. That will resolve all the problems with that engine.

 

GOM - Your 2.2 has a headgasket failure. That's why you can't run any cooling system pressure. Yes the 2.2 will blow head gaskets as well.

 

GD

Edited by GeneralDisorder
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Thanks, Tex. I'm just really busy these days - not much time to post. I can be reached at my email though:

 

rick@superiorsoobie.com

 

Lostinthe202 and I will be independently developing some EJ257 deck plating for high boost applications. To get much past 25 psi you need to reinforce the top portion of the cylinder liner/wall or you will peel it open like Elmer Fud's shotgun where the reliefs for the case half bolts are located.

 

post-49-0-64935900-1486836436_thumb.jpg

 

GD

Edited by GeneralDisorder
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That's what we will be doing, yes. But Lostinthe202 will be doing it from scratch not a copy of anyone else's (he is what I would term a "master machinist" and that might be understating it) and we have some features planned to improve upon what's out there currently. Both to reduce costs and to improve cooling efficiency and strength.

 

Their claim that you need a closed deck for 10 psi is quite untrue. Subaru runs more that stock. Don't know where they get their info. We run upwards of 20 psi on the open deck EJ205 without problems unless you get too lean. We recently had a 257 blow out a cylinder around 22 - 24 psi because sediment in the fuel system got through a failed filter and clogged up the 1000cc injectors. Two of them flowed only 550cc when I put them in my flow bench.

 

GD

Edited by GeneralDisorder
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cool!

 

are there special filters for high volume fuel pumps? I never thought of that before. I bet those folks running E85 are pushing a lot of volume.

 

anyway, sounds really interesting - wish I had the time/money to boost my WRX more. For some reason, I just destroyed my second gear - stock power and only 63K miles. I hope folks are doing 6spd STi trans swaps with all that new power.

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No usually the stock filters are fine. This one was just plugged and the high volume pump blew through it. Too much back pressure. After about 05/06 Subaru removed the serviceable filter and put them in the tank so it's rare we have problems with most builds being newer than that now.

 

You can get 4.444 final drive 5 speeds from Japan for cheap these days. The last two I have bought came with rear diffs for $800 delivered.

 

GD

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No pressure cooling systems can work fine in cool climates or low altitude areas. At higher altitude the boiling point of the coolant is lower, and you need a pressure cap to increase pressure in the system and prevent boiling.

 

The proper ratio of antifreeze to water also goes a long way.

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Update:

 

Well, I guess it was a sticky thermostat after all as I haven't had any trouble since i replaced it.  That said, I haven't really been on any continuous multi hour drives.  Farthest I've been so far is about an hour of run time with a four hour break in between, so jury's still out, but I'm cautiously optimistic. Seems like every time I've had cooling trouble in the past, the thermostat is always the first suspect, and the first cleared of all charges.  Maybe this time he actually did it.

 

Thanks for the brain lube everybody!

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