Special additive for cooling system?

"Tony Hwang" wrote

So the finally got around to you? I don't know what is in it, but it miraculously extends the head gasket warranty to 100,000 miles. I have a feeling it is nothing more than a Stop-Leak type of chemical.

It is Subaru's fix for their leaking head gasket problem. They will no longer pay under the warantee to replace the head gaskets unless the additive fails to work. The offical Subaru name for this stuff is: Cooling System Conditioner. Part number SOA635071. The cost is about $1.75. Much cheaper for Subaru than having a mechanic replace head gaskets.

The stuff is likely the same as Holts Radweld. Container is the same shape, same quantity (125 ml), same color (blue) container with a red cap, and even has the HOLTS name near the bottom. Also says "Manufactured in England for Subaru of America, Inc."

See:

Takes about 15 minutes? If one whose car was past

Jim

The dealer replaced the head gaskets on my '01 back in December. I've heard they try the sealer first now. I had the sealer added about a month ago, also bought an extra bottle ($1.50) for when I flush the system again.

Mike

So in other words, they haven't fixed the head gasket problem yet?

You remove about 4 ounces of coolant then add the conditioner (stop-leak)then run for a minimum of 15'. I personally would do it for longer with the heat for the cabin on as well. You must do this each time you change the coolant.

For the poster with over 100k, is your engine one of the earlier 2.5 SOHC engines? Have you changed the t-Belt.

I would consider swapping my water pump at the same time.

Marc

Two weeks ago our 2002 outback blew a head gasket at 38,000 miles. It was an INTERNAL leak. Thankfully, it was covered under the regular warranty and so we didn't have to pay for the repairs. But this does raise many questiions and concerns. Since Subaru has been doing all the maintenance on our car including summerizing an winterizing, how come they did not see fit to put in the special coolant before this happened? (Or maybe they did)They did after the head gasket job.

There is that 100,000 mile warranty but it is only available for outbacks with specific VIN #'s. Ours did not meet that criteria. Also this warranty only covers external leaks, not internal which our was. I am incredulous with the coolant additive as a cure for this problem. We will certainly be SOL if this happens again between 60-100,000. Why did Subaru build such an engine. Is there any recourse? Did my trade-in value just drop considerably because of this?

So why wouldn't the coolant work for internal leaks as well as external leaks? What would cause an internal leak that would require Subaru to make such a distinction? As far as we know we did not put undo wear and tear on this vehicle. As a matter of fact, this past year we parked the car from mid-Aug till mid May because of where we live during those months, there are no roads in town and no roads to town. We have to fly in. We did drive it around during christmas break and once or twice during the fall and in February when we were in the city. We do use it during the summer for travel and taking care of business. That should not have caused an "internally" blown head gasket.

By the way, we never did receive notice about the conditioner.

Are located in the USA? If so, make sure that you are listed as the owner of record on the Subaru USA computer. If you have moved, they may not have your correct address.

Does anyone know if this "service advisory" was sent out in other countries?

Ed: I was told by my service writer that this letter went to all owners of 1999-2001 SOHC vehicles. And yes, it only covers external head gasket leaks.

He also told me that this sealer is the "treatment of first resort" when a customer comes in with an external coolant leak on all SOHC vehicles, including those under warranty. If the sealer fails to cure the leak, then they tear down the engine and replace the head gasket. However, (under warranty) they only replace the gasket on the side that is leaking......... leaving the owner to constantly wonder when the gasket on the other side will fail, too.

It is not sent out in Canada. Had to call Subaru Canada to confirm it was available and we don't get an extended warranty (yet)... :(

Nicolas

Another thing you can do is let your car warm up for a minute or two in those cold temps before you go roaring off. That will give the engine a chance to adjust without a lot of stress on it.

Hi,

I had a long talk with my friend who owns a machine shop when I blew a Toyota head gasket. In one of our cooler Februaries (SoCal, so it doesn't get THAT cold!) He said the kind of use you describe is exactly what causes a LOT of blown headgaskets, regardless of make.

His explanation was that colder weather causes much more expansion/contraction of the heads, gaskets, etc., and what happens is you go out one cold morning, fire up the engine when things are contracted, therefore "looser" than usual, and probably blow the gasket within a few blocks. He pretty much had my situation described perfectly.

On the bright side, he also said if you surface the heads the first time you blow a gasket, the chances of another blown gasket go WAY down. He said that's cuz the metal has pretty much done its shape distorting expansions and contractions--"cured" for lack of a better term--and now will hold a flat surface better. Again, he described perfectly what I experienced once the engine was buttoned back up.

Since the Subie engine has more aluminum than most, it stands to reason perhaps there will be more "motion" of the metal in that engine, especially in widely varying temps. It's anecdotal, of course, but my Subie needs coolant about once a week during the winter, once every coupla months once it gets warm and thru the summer.

Hope yours treats you well now that it's been fixed!

Rick

I've been missing a few messages the last couple weeks, so I apologize if this has been answered already...My '99 2.5l Outback wagon is well out of warranty, and replacing a head gasket is the last friggin thing I need right now. Should I get some of this additive as a precaution?

BTW, I just got this car in February. Looking at the engine closely, it's been steam cleaned but there's some oil mess in places I wouldn't expect from normal use and refill spillage. Almost like the gasket blew once and it's been repaired already. Is that likely?

-John O

Hi,

Previously replaced gasket's a possibility, but considering the car's five+ yrs old now, I'd also add valve cover gaskets, camshaft and front main seals to the list of suspects. A lot of people don't do it, but it's a good idea to replace these at each timing belt change.

A sluggish or clogged PCV valve may also cause some oil leakage at the hose junctions. Take a quick look at the oil pressure sending unit, too.

Rick