Guys,

Its time for me to do a coolant flush. What is the current thinking on the proper coolant for our sharks? Which brand do you all use?

Anything special I should know before flushing the system?

TIA

Brian

 

Current thinking is.....different. This is a another religious thing. There are many discussions, and postings of pros and cons of all types, horror stories about all brands. My summary would be: use the old fashioned green Glycol based stuff (no silicate or something else bad type) if you are happy to do regular (2-3year) flush and replace; try the Orange Dexcool long life if you want longer between flushes (5 year claimed), and are happy to face The Challenge of The New, etc.
I am on Dexcool since last TB&WP in late '01. Car had green stuff in it, and interior of engine was VERY clean and shiny. Where I am now Dexcool is less freely available, but there are other brands of course, so next TB, who knows?
jp 83 Euro S AT 49k.

 

One thing is unanimous: everyone here will tell you something different.

I use Prestone Lo-Tox and distilled water, 50/50 ratio. I change my coolant at least every other year.

Porsche doesn't recommend this stuff because it contains propylene glycol instead of ethylene glycol. The PG makes it non-toxic, but it has less inherent anti-freeze [I live in Fort Lauderdale...] and anti-boil capability, and it needs a stronger anti-corrosion package to be safe for your engine.

I have used it for 5 years with good results. And my car runs at the first white line on the gauge consistently, even in traffic in 90 degree heat with the air conditioner on.

Basically, any name brand will do as long as you change it regularly. Use distilled water!

N!

 

The green stuff.

 

Peak global extended life. Did a lot of reading about this and landed on this one.

normy was right.

 

Prestone Dexcool The RED stuff

 

Dexcool(orange)... 1 gallon, add a pint of Redline water wetter, top up with distilled water.

 

The Green Stuff......... No Wait The Red Stuff...........No WAIT The Orange Stuff........... OH H#$% I Don't Know...... The Green Stuff........ NO WAIT

 

Ya know I was just thinking the same thing today so I went out and purchased Prestone DexCool (the orange stuff) today. I have not done the flush yet as i am trying to think through the best way to flush the system with out getting hot spots. Any advice on flushing this engine before I start tomorrow morning?

Since NOTHING IS EASY ON THIS ENGINE, I'VE GOTTA ASK!

 

Yeah, you've got the idea!

 

It actually is easy IMHO, but time-consuming. There is a tip from dr bob on Nichol's site about flushing with a garden hose while with the t-stat out here.

I went about it differently and I'm happy with the results so far. Note that what that means is, no related catastrophe in the past year and the coolant is still clean. First, I pulled the small bleed hose off the front driver side of the rad, then drained the system, including both block plugs.

Then I put all of the plugs in, just a taste more snug than finger tight. I filled with tap water till I saw water at the bleed hose, then put the hose on and filled till the reservoir was full. I did this with the car parked on a slope(driveway) with the nose uphill. The reservoir was still the high point in the system. I just ran the car till I had hot circulation(heater on), then shut it down and drained it once the water was below scalding temp and repeated. I then repeated twice with distilled water to be sure to get all of the impurities out that I possibly could.

Then after draining the second round of distilled water, I put the block plugs in with fresh sealing washers and torqued to spec, put the radiator plug in with new copper gasket and tightened, and poured in one gallon of the preferred coolant(Orange Dex in my case) followed by the wetter and then topped it up with distilled water to the level where it sits now.

It may have been a bit overkill to flush it so thoroughly, but as I understand it one thing that can turn out REAL bad is if you mix incompatible coolants. Also I was putting in a spankin' new radiator. Since I didn't know anything about what was in there except that it was green, I decided to play it safe. If you know exactly what was in there to begin with, and can establish for a fact that it is 100% compatible with what you want to put in there now, then I'd say do one tap water, one distilled water, then fill.

 

or was it orange...

 

something phospate free.

 

uhhhhhhhhhh.........ok.........I think



Anybody use Radiator Flush (Prestone, et al)? Does it help clean out the gunk?

Brian

 

Just put in Zerex G05 'Guaranteed to meet everyone's specification' coolant. The color is....(drum roll please!) pretty much the same as the water. I had previously used the Prestone Orange extended life phosphate free stuff, but Prestone doesn't have that here anymore. Instead, they market their yellow/green product as extended life now.

Meanwhile, the M-B, VW, etc cars with aluminum components accept the Zerex G05. I think Earl Gilllstrom posted some of his research on the subject too, pointing to the G05 rating as what we need.

I put in 1.6gals of coolant, a bottle of Water Wetter, and about 1.75 gals of distilled water. I'm guessing the last 1-2 quarts were captive in the heater core or something. The car sat for a couple weeks with the radiator hoses out, the block drains pulled, and the radiator drain removed, all while the T-B/WP/coolant hose replacement was going on here between project assignments. The radiator drained an almost continuous dribble of coolant over the course of those weeks, to the tune of a 2" puddle every day from the lower-hose port. The block sat with the plugs finger-tight, and still managed to puke a couple ounces from each one when they were removed at the end for reseal/retorque prior to engine fill. For most of the duration, I ended up keeing a bucket under the hose nozzle there to catch the dribbles. Where did all that stuff come from??

Anyway, with all new hoses, a new radiator cap, new coolant circulated by a new water pump, it runs at exactly the same temp as it did before: right around two widths below the last white line (would be 190F by my estimation...), with a drift up above that line on a hard slow-speed climb in 95F with AC on full, and heater valve open and bypassing the radiator.

On the flush: Decide what gunk is, and what you plant to do to neutralize the cleaner. Some of the products on the market are just a little caustic, and require a really intense flushing after their use. Be careful. I've had good results from the Prestone flush (the one that comes in the mini yellow bottle that looks like an anti-freeze bottle) on other cars, great results. Again, lots of water. Note that they want you to drain the old coolant out, water flush, and use the flush chemical in just water. Drive for a day or two, then drain/water flush/refill with correct coolant. The stuff in the chemical flush is a contaminant in your coolant, so it all needs to be washed out when you are done cleaning.