Over the last month or so my 98 forester would randomly overheat. It doesn't gradually increase in temp but within 30 seconds it goes from normal to the red. After it cools I can refill the radiator and it may run a week before it does it again. The last time it did it it I shifted to 4th gear to bring the rpms up to about 3000 and it immediately went back to normal. Usually the excess in the recovery tank will refill the radiator. I don't think it is a head gasket because I don't see bubbles in the radiator and it hasn't changed since it started. It seems like the water pump stops circulating. Could the problem be the tensioner and the belt is simply slipping on the water pump pulley? I picked up a new waterpump and timing belt yesterday. The question now is how do you get the bolt out of the crankshaft pulley? It is a manual transmission but am not sure if the bolt has RH or LH threads. Also can I loosen it by putting it in 5th gear and just use a socket and breaker bar? I bought the car with 127,000 on it a few year ago and now have 165,000 so I think I should change the belt and pump anyway. I'm sure the previous owned changed the belt @ 80,000. It uses no oil and runs perfectly otherwise. Thanks

Yes, you can put the car in 5th gear, have someone stand on the brakes and you can loosen the main crank pulley bolt. It has normal threads. Left to loosen.

 

Make sure you re-tighten the bolt to 120 ft-lbs, and it's not a bad idea to put medium strength locktite on there.

Thanks for the reply, but I got the bolt loose by using the starter method. I just found this site this morning and have been doing a lot of reading. The more I read, the more I think I have a leaky head gasket that is causing the air lock periodically. Usually the recovery tank is overfull and it doesn't suck back when it cools. I can't really say there are not bubbles through the radiator, they are not apparent at idle. Should I put it back together with the new belt and pump and see what happens or pull the engine and do the head gaskets? There wasn't a thing wrong with the pump that would cause the overheating so I would expect the same simptoms later. I wish that I had found this web site before I started with the project. I'll welcome any advice. thanks

Its up to you but if it was my car I'd change the head gaskets and check all the other usual stuff like valves and oil seperator while it was out.

If you are going to keep the car, get a rebuilt engine from CCRengines.com.

 

They build them right and over the long run it will save you money!

 

I purchased a Legacy from a lady who paid a Dealer almost $2800 to do the HG only to have the engine go with a bad rod a few weeks later. The mileage was 152K.

 

You could also put in a good 95 2.2 engine. Its a direct bolt in. In eithe case, your head gasket problem will be Gone.

Pull the engine and replace the head gaskets. Be sure to replace the seperator plate, rear main, and o-ring while the engine is out. Only use oe Subaru head gaskets, and have the heads surfaced.

ditto to what color blind said. I just did a 96 OB with the same exact behavior.

 

Mine had 152k. When they pulled the engine and looked at the heads and cylinder walls, my mechanic was amazed at the lack of wear in general.

 

It is running great now. I would get the gasket kit from 1st subaru parts. They provide genuine parts at a discount. While it was out, we did the timing belt, water pump, seperator plate, cam seals ......you get the idea.

 

It should be about $1200-$1800.

 

Make sure you flush the radiator out well also.

 

Good luck!