Ok, we bought an 98 legacy gt limited 2.5 about 6 months ago, replaced both head gaskets, oil seperator plate, numerous sensors, gaskets, and all belts. now we have a coolant leak and we're getting code p0420. Ran seafoam thru a tank of gas but it really made no difference in performance or mileage. This car runs and drives great but it's nickel and diming us to death. Sorry for the rambling but this forum got us thru the tear down and rebuild and I find the info from the experts invaluable!

Ok, we bought an 98 legacy gt limited 2.5 about 6 months ago, replaced both head gaskets, oil seperator plate, numerous sensors, gaskets, and all belts. now we have a coolant leak and we're getting code p0420. Ran seafoam thru a tank of gas but it really made no difference in performance or mileage. This car runs and drives great but it's nickel and diming us to death. Sorry for the rambling but this forum got us thru the tear down and rebuild and I find the info from the experts invaluable!

 

How big a coolant leak, from where? If it's from the HG, bad. I recently read a thread very closely, about proper torque-detorque-retorque sequence for headgaskets. It is involved.

 

Plugs and plugwires, you changed, of course? Std. maintenance.

Try seafoam through a vacuum line. I usually use brake booster and pay attention NOT to stall it out until you're supposed to.

 

As stated where is coolant leak from?

 

If you're on here I ASSUME you used OEM HG's and the latest Head Torque procedures(the Mexican had dance of HG installs).

 

Often folks have trouble with lower rad clamp if they pulled the rad.

 

Is it the WP (and a generic cardboard gasket) or from the HG?

 

Gotta give us a little more to work with. Heck the hoses to the heater core couild be loose.

We only used oem parts for the whole rebuild as the members recommended. All plus and wires are also new. This was a first time but I was very careful with adjusting torque. The leak is from somewhere in the very front near the radiator. I can only see it dripping, actual spot isn't visible, I plan on tearing more into it today. it started out as a very slow leak, even unnoticeable, but has progressivly got worse and now i add coolant every other day. Can you be more specific on seafoam in the vac lines? Thanks for all the help!

Seafoam for your problem is best introduced through a vacuum line. May be worth a youtube search. It'll cause a cloud of white smoke so bad the neighbors may call the fire department.

 

I gave up on finding a small hose arounf the throttle boday and jsut use the big hose that goes to the brake booster. I keep pouring some into an old rattle paint can lid (white or yellow) so I can see the level of seafoam because it can be easy to stall the car prematurely.

 

If the coolant leak is up front on drivers side that's the rad, rad/hose connection, hose/plastic WP outlet connection, Thermostat(and Oring) or waterpump.

 

Did you get the thermostat in correctly(it's pretty obvious on an OEM thermostat when it's in backwards, aftermarket not so much.

 

Did you have trouble with that Oring over the thermostat?

 

Did you get the rubber coated metal WP gasket from the dealer and install it dry?

 

I'd start by checking that lower ran hose's clamp.

 

Hope its not coming from the overflow bottle.

 

Did you follow the instrustions (and/or video) here on how to burp?

Well, the few free minutes I had, I did see that the leak is coming from the back of the motor, almost directly in the middle. Unfortunantly, I'm an HVAC tech on call in 90+ so the seafoam will wait until sunday. I did use an oem water pump, gasket and thermo. I'll dig into that leak later today. I need to pass e-check soon! any info on the spacer cheat for the 02 sensor?

The seafoam and/or the double stacked spark plug non-fouler's have worked for every 97 I've done. Not many - probably a half dozen 97's.

 

Certainly worth the effort given the alternatives.

 

I often find it handy to get a dye kit. Then with a black light from the kit you can see better where all whatever fluid that's leaking is. Much more effective then the naked eye. And when hard to spot it's easier at night to see.

 

When I had trouble (3 replacement engines to get a good one) for a 99 Forester I broke down and bought a complete kit with stuff for coolant, oil, and AC dye's for like 100 bucks. Comes with black light with long leads to go to battery(I use my jump box), goofy glasses, etc. in a nice green plastic case.

The antifoulers are available through Autozone part number 42009. They're about $6.50 for the pair.

You'll have to drill them out.

I have a pair already drilled out that didn't work on my 05 but everyone swears by them pre 05. Good luck.

PM me if you want them.