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I know this has been covered ad-nauseum, but I have a couple quick things to clarify.

 

Blew a head gasket (or a least discovered it today). Called a mechanic friend who suggested contact the dealership and ask about the "conditioner" before sporting for the tear-down. The guy at the dealership said they've had some luck stopping leaks w/ the conditioner. However the Phase I&II FAQ says very clearly that it does NOT. What's the word, is it even worth trying?

 

Also, while I'd like to give my friend the business, everybody says to go to a specialist. He's done the job before, but I'm not sure that makes him a specialist. Is being a competent mechanic not enough?

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I know this has been covered ad-nauseum, but I have a couple quick things to clarify.

 

Blew a head gasket (or a least discovered it today). Called a mechanic friend who suggested contact the dealership and ask about the "conditioner" before sporting for the tear-down. The guy at the dealership said they've had some luck stopping leaks w/ the conditioner. However the Phase I&II FAQ says very clearly that it does NOT. What's the word, is it even worth trying?

 

Also, while I'd like to give my friend the business, everybody says to go to a specialist. He's done the job before, but I'm not sure that makes him a specialist. Is being a competent mechanic not enough?

 

I think if it's leaking externally, I'd give it a shot. But I doubt it can seal against cylinder pressures if the gasket has failed that way.

 

Carl

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I know this has been covered ad-nauseum, but I have a couple quick things to clarify.

 

Blew a head gasket (or a least discovered it today). Called a mechanic friend who suggested contact the dealership and ask about the "conditioner" before sporting for the tear-down. The guy at the dealership said they've had some luck stopping leaks w/ the conditioner. However the Phase I&II FAQ says very clearly that it does NOT. What's the word, is it even worth trying?

 

Also, while I'd like to give my friend the business, everybody says to go to a specialist. He's done the job before, but I'm not sure that makes him a specialist. Is being a competent mechanic not enough?

 

OK, let's take this one step at a time. First off, please tell us exactly what year and model of Subaru we are talking about here? Knowing exactly what engine we are talking about greatly improves our chances of giving you good advice.

Second, the mechanic friend was trying to save you a few dollars, as the conditioner is a lot cheaper than the parts and labor to replace a headgasket. At least, that is the theroy. The problem with the conditioner is that it is little more than "Stop-Leak", and has been known to seal "leaks" that were actually passages for coolant. Passages that were in the heater core, the radiator, inside the engine, etc. . . Not good. Additionally, this "solution" was only for the SOHC 2.5L engines. For the DOHC engines, you had to replace the headgasket in any case.

 

My recomendation is to have the headgasket work done, and skip the "conditioner" as it can cause a lot more problems than it solves. If your mechanic has done this job before, you should be fine providing that he has correct information on the engine (torque specs, valve clearances, etc). In that he tried to steer you toward an alternate solution, I suspect that he has enough respect for the dificulty of the operation to use the care needed to do it right.

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Sorry about that. It's a 2.5L Phase I, DOHC...'98 Leg GT. Gunk and bubbling in the res. and the test for hydrocarbons was positive. I gather that means it's an internal HG.

 

I'm sure I'm showing my ignorance by asking this, but will they replace both sides, or am I confusing the internal with the external HG?

 

Thanks for the help so far.

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With that engine and with evidence of an "internal" (i.e. into the coolant loop) leak, don't bother to try the conditioner first -- it won't help. Since it can be devilishly difficult to determine which side is leaking it is best to have both sides replaced. The good news is that using the redesigned headgaskets for this engine fixes the problem without subsequent worries on 95%+ of the 2.5L DOHC engines out there. I don't think that this job is beyond the capabilities of any experienced mechanic. They just need to be aware that there is very little clearance to work if the engine remains in the car, so pulling the engine may be a more time-effective solution than doing it in-situ. Also, the mating surfaces need to be cleaned completely, wihout scoring or otherwise damaging the metal. Just the usual common sense precautions when working on any soft-metal block or heads.

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Replace both headgaskets. Do this with the engine out of the car. have the heads checked for flatness, and decked only if needed. While the engine is out, I would have them replace the plastic oil seperator with a metal one, as the plastic version has a tendancy to crack. Subaru discovered this themselves, and (IIRC) they only provide the metal ones now. Also replace the cam cover gaskets, the cam seals, the oil pump O-ring, and the grommets that go on the bolts that hold the cam covers on (there are also O-rings that go around the spark plugs. these should also be changed). While doing all this, it would be a good idea to replace the timing belt, and tighten up the screws on the backing plate of the oil pump. Once all this has been done, you should be able to rely on the engine for a good long time to come. I have done several of this particular operation, and have had no problems with any of the engines that I have so serviced. One note: the cam berring caps take 14ft-lbs, the caps that hold the cam seals take 7ft-lbs. Some of the manuals out there incorrectly list both at 7 or both at 14, causing problems.

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