Radiator coolant

I always stick with mfrs coolant..Por gets pink fluid,,,Honda gets blue fluid,,i dont buy the generic equivalents..im guessing Sube uses the blue fluid

Yeah, since there are several different coolants out there AND some may not be compatible with others, it's best to find out what SE uses in their Suby cars and use that.  All we can do is speculate and your don't want us to inadvertantly steer you wrong and screw something up.

Wait to hear from @chines1

Hi Stuart,

My experience with a Subaru engine in a replica is that you want the minimum amount of coolant additive possible, which depends on the annual temperature variations of your area.  If you get a hard freeze, more ethylene or propylene glycol is necessary.  However, maximum heat transfer occurs with plain water.  All other additives decrease heat transfer efficiency.  Since we are car guys, there are lots of discussions as to what type of water works best: tap, distilled, de-ionized, etc.

There are also additives that advertise additional cooling benefits, such as surfactants, that reduce water surface tension, and products such as Water Wetter, that advertise additional cooling benefits.  In addition, water pumps need lubrication to prolong life, so that means another category of additive to coolants.

Air flow through the radiator, coolant speed through the engine, and square footage of rad itself, as well as rad thickness and number of coolant passes in the rad, are all factors that affect engine cooling efficiency.  Cooling fan efficiency, puller vs. pusher fans, and the necessity of an efficient shroud that forces all cooling air through the rad are all elements of keeping coolant temps within range. 

However, the main factor in my experience that raises coolant temp is ambient air temperature.  When air temp rose over 80F, I could expect increased coolant temps.  There are some operator steps you can take to reduce coolant temp, such as lowering engine rpm's, not turning on the a/c, etc., but I'm sure you are taking those steps already.

If your fans come on automatically, you may want to check to make sure they are coming on at the intended coolant temp, and, if you have two fans, that they both come on at the proper fan speed, if you have more than one fan speed.  Depending on your application, there are thermostats that can be adjusted for the fans to start at a lower coolant temp, which can help keep coolant from overheating.

The crew at Beck's is not only talented, but honest as well, and committed to customer satisfaction.  I can think of no other maker who will go further to help solve your problem.  Please keep the group informed as you progress.  That's how we all learn.

Overheating? Fluid Loss?

Dont wait a year to check your radiator cap, like I did on my 968. Sounds stupid, but I carried gallons of $40 coolant from coast to coast until a friend suggested I check my cap.

Looked fine, but a new $8 Stant from checker auto fixed me all up.

Subaru has their own radiator coolant, that contains a conditioner, which helps to keep the head gaskets from blowing.

I would only use Subaru coolant in a Subaru engine.  And I do.

Subaru SOA868V9210

Subaru conditioner is Holt's Radweld, rebadged for Subaru.  It's basically another type of Barr's Stop Leak, actually designed for model years 2006 and older.

I'm not a Subaru guy, but I know enough to know that the cooling system is a weak spot, and I've read enough on this site to know that nobody here (aside from maybe Carey himself) knows more about Subaru cooling than Jim Kelly. But as a guy who deals with heat transfer for money every day, I can tell you his long post above is true in every detail.

Water is a more efficient coolant than glycol (polyethylene, polypropylene, etc.) . There are always other considerations, but for straight heat transfer, glycol of any kind reduces efficiency. The stronger the mixture, the weaker the heat transfer.

@Jim Kelly posted:

Subaru conditioner is Holt's Radweld, rebadged for Subaru.  It's basically another type of Barr's Stop Leak, actually designed for model years 2006 and older.

Yes, it's basically a leak stopper, but it's recommended by Subaru.  I use it in our older Subaru Impreza, but I know of others that use it in newer ones.

Carey is the one who can advise you Stuman, as the design of your system is his and he knows the trigger points for the fans etc.

After chasing down the leaks or air pockets after bleeding the coolant system even the type of coolant that they use I would match.  Some Becks also have an auxiliary pump on the older cars.   I won't even talk about never change coolant like Evans .

Best of luck but Careys is your man.

Coolant debate is like oil debate and everyone has their ideas of what to use and what not to use.  I am far form the coolant expert but one thing I do know is you are not supposed to mix colors heavily.  I've seen instances where certain additives will have a bad reaction with other additives and coagulate.

As for what we use: We use Prestone DexCool (orange) with a water wetter additive (1 bottle).  Although I've heard GM techs say DexCool will corrode, clog, etc, we have not excperienced that at all.  Likewise, I've heard to ONLY use Subaru coolant (blue), with mixed reasons as to why (head gaskets, radiator lifespan, etc) but have not experienced this as necessary...

BTW, I got your e-mail @Stuman but my reply says undeliverable.  Not sure if it actually went through or not, but based on your pic, I'd say you had a trapped air bubble, or several small ones that accumulated, and have now purged out of the system, leaving the radiator low.  Top off your radiator, make sure you have a little in your overflow (make it 2" or so just for good measure) and give it a shot.  You may have to repeat a time or two, but that should do the trick.

I figured this question would have many different answers.  However, Carey’s solution did the trick.  I added a bottle of water wetter and topped it off with dexcool and drove around for about an hour with outside temps in the mid 90’s and the temp never went above 217 on my OBD2.  Problem solved thanks to the boys at Special Edition.  Many thanks to all.

Not sure what Carey uses on his cars but, the piping is somewhat long on our cars with front radiators, bleeeding the system is an issue that you have to address properly, and if you find the fluid going down, check to see if it is coming out of the overflow tank/tube on your driveway or garage floor after a ride, this happens to some if they do not have a second overflow tank, all turbo's have two tanks and hence adding one might help.

Despite vacuum bleeding the system, it is not uncommon for there to be a rogue bubble, or more accurately, many very small rogue bubbles, trapped in the system.  Over time they work their way to a high spot and gather, and then are purged out of the system all together.  The length of the coolant hoses and the rollercoaster pathway certainly exaggerates the issue.