GOM

My 98 Forester with its high mileage transplant has 200k on the body and about 230k on the engine. This the third engine in the car, the first two during previous owners and this one installed by me since I despise the 2.5's with their quirks and will only have a Subaru if I can have a non-interference engine (the 2.2). My body is rusting away rapidly, but the engine is a superb runner, doesn't use enough oil to add between 3000 mile changes, doesn't use coolant, and is extremely reliable. They should have built the Forester in this combination and avoided all the bad feeling created with the often-broken 2.5's.

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!

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!

Has anyone found an interchangeable temperature sender from another vehicle that will make my 98 Forester's gauge read coolant temperature accurately. It now is like the famous Ford "dummy" oil pressure gauge in that my temp. gauge seems to read in mid-range anytime the coolant is anywhere from mildly warm to near meltdown. I'd like to see it actually read like some other vehicles do, fluctuating when the thermostat opens or closes, varying under load, and so on. As near as I can deduce, the temperature sender does not send a proportional signal to the gauge but is weighted heavily "mid-scale". I'd like to think that a sender from some other application would fix my frustration.

As a subie newbie this kind of information is just what I'm usually looking for. I can't resist the urge to make things work the way I want them to, not the way the manufacturer thinks I want them to. I'll just about get my new old car the way I want it and the northeast's rust and road salt will consume it (it has happened many times before!) The extra photos made all the difference-- thanks.