Anyone drain their radiator ~once a year?

[JHZR2]

Hi,

I dont like doing a coolant job... removing hoses scares me, I dont want to splice into them for a prestone type flush job, and I like to use OE fluid. The reasonable thing for me to do as such is simply to take the cars to the dealer once in a while to get a real coolant flush, with the dealership machine... Maybe they even take out freeze plugs.

However in between, every year or so, is it smart to drain the contents of the radiator, and perhaps even leave the drain cock open and flush hose water then distilled water through... then refill with 50/50 fluid?

It seems to me that this would keep the radiator clean, would top off a good portion of the cooling system fluid with new additives, and keep the system better than if it wasnt done.

However, opening the system may be a bad thing, and should be minimized.

I know in my chevy truck, opening the radiator cap and drain cock, even while still quite hot (just cool enough so it doesnt flash) doesnt allow more than the radiator to drain. In order to get it all, I need to pull a hose... I assume its the same on all of my cars.

My 83 MB 300D has the original radiator and hoses, after 228km ad my 91 BMW has same after 102k. Neither of these had yearly flushes, but the MB got a regular citric acid flush at the correct interval, to keep things like new - and it worked.

It seems to me that topping off additives and getting rid of rust is a good thing... ANyone do this, or is there a reason not to?

Thanks,

JMH

 

[Willy_G]

I drain green ethylene glycol every 2 years. I just open the lowest access point, usually a draincock or hose on the pump. I don't do an entire flush. Never had an un-expected cooling system failure yet!

On my longlife Dexcool and G12 cars, I have yet to do any drains/changes. Usually don't keep the cars long enough.

 

[ALS]

I do as Willy_G does every December with fresh Volvo Coolant. The car gets 20K miles put on her each year so I feel it is enough miles to justify the expense. My Sunday car gets a coolant change every two years since she only sees 5K miles a year.

 

[Winston]

I drain and refill my radiator every two years. I would never trust the dealer because I am sure they would put tap water in.

 

[9c1]

I drain, flush, and add new coolant every two years. Both green and orange coolant. I am told green is getting harder and harder to come by. I might have to alter the coolant I use, but two years still seems like a good interval
Terry

 

[Win]

Every other year in the Fall, I park the vehicle nose down, and pull the lower radiator hose and let the block and radiator drain.

I use DexCool in the Jags, and green in everything else. The only car that ever has air pocket trouble is the Jag V12 - it takes a bit of time to get all the air out of it.

This kinda stuff is cheap insurance against cooling system problems, like a tranny drain every oil change will make an autobox last practically forever.

 

[olympic]

Most engines have a coolant drain plug(s) in the block. Every engine is different but generally they'll be visible from underneath and slightly above the oil pan and have a hex head on them. If you remove them and open the petcock on the rad, you'll get 99% of the coolant out. Don't forget tho remove eand clean the recovery tank as well! Follow up with a good garden hose flush, close everything up and refill with coolant/distilled water.

Even on my Montana vans with their jam packed engine bays I can get the plugs out fairly easily. The front one I can reach with a socket and long extension, the rear plug requires me to get under the van and reach over the transmission (blind of course) and remove the plug with a wrench. Then bid a hasty retreat before being drenched in coolant. It's a bit of a hassle but I use Dex-Cool so I only have to do this procedure maybe twice in the lifetime of a vehicle.

 

[kgb007stb]

Wow, everyone in here is on the two year plan which is good because that is the plan that I am on as well. Here in So Cal 110 is just the order of business in the summer and I never had a problem with any of my cars including cars 15 years old. I never bother with a flush, I just drain the fluid and re-fill. There is barely any dirt in my coolant after two years and it comes out all clean not smelling one bit, as opposed to some people who do not maintain their system and the coolant comes out looking like crap. With the AC on full blast, I have yet to see any of my cars overheat, I have all original water pumps, I guess the fresh fluid keeps the seals in check.

Would it be advisable like some of you mentioned to take off the radiator hoses and flush it with a garden hose to get any debris out. I maintain my cooling system and therefore I do not see any rust and I hesitate to use chemical flushes because I do not want it to eat away at the seals, hoses and gaskets.

 

[H2GURU]

Lubeoiler,
This air trapping event is usually a problem on smaller imports with a low slopping hood. It occurs when the filler neck is not the lowest point in system. Any trapped air in cooling system is always bad. I wonder if running the engine a couple of days with heater on and filling as needed would purge system of air? I do believe that a shop would draw a vacuum on it and add fluid.If you had a MIGHTY VAC (oil extractor)you could rig up something that would work.

 

[H2GURU]

An annual simple drain & refill of your radiator will go a long way in preserving your ride.Take care when purchasing fluid as there are now many different types that are not compatable. The heating and cooling along with the many different alloys and plastics under pressure, ravages a lot of vehicles. There are many more autos in the BONE-YARD from lack of coolant changes than from lack of OIL changes! Life-time coolant is a HUGE CROCK.

 

[LubeOiler]

After doing this quite a bit lately I have learned what seems to work. The question about air pockets are a issue but found some good stuff on other sites. For the most part 2 years seem to be what is recommended. I did a Toyota, the pitcock is very easy to use so I drained the radiator filled it up about 1/2 with distilled water and let it heat up with the cap off. After the thermostat opened I filled with more water and put the cap on.By the way the Heater valve needs to be OPEN throughout this drain.I drove the car hard for a few blochs and came back and drained the radiator. The cooling system way slightly red so I got most all of the fluid out by now.Since the cooling system fluid looked pretty good I just refilled with Prestone 50/50 or go back to Toyota antifreeze.I did not completly fill the radiator yet. I raised up the front end to allow any air to escape out the filler neck.As it heated up I put the cap on and drove it rechecked the level and toped off the overflow bottle.This may seem like a hard way to do it but it works for me it took about a hour total. That is removing the cover on the bottom of the radiator too.The air issue is something I never ran into till I did my Nissan Truck. They even have a air bleed screw by the thermostat.

 

[blupupher]

I plan on a once a year drain of the radiator. I put on around 20k a year. I will do a complete flush @ 60k when I replace the hoses and t-stat.

 

[TheTanSedan]

Once per year on all fluids is peace of mind. Especially if personal finances ever go belly up. Good to have some margin on operations.

It's also a good thing to inspect hose interiors for wear. Double-check on getting block drains out (run tap thru threads and coat all threads with anti-seize before re-installing (try to keep out of coolant).

Be sure to re-test coolant after a few hundred miles (and having run heater system) for by-the-book freeze properties.

De-ionized water is preferred over distilled is preferred over tap is preferred over well/aquifer.

I have used SCHAEFFERS #158 Clean & Cool and am now trying RADIATOR MASTER RMI-25 as additives for long-term lubricant and cleanliness.

 

[Robbie Alexander]

I have about one dozen Toyota Coolant jugs in cases just ready for use, about every year or thereabouts I drain mine and sometimes I flush it, usually when it hits high milage.

JFYI, I have 75K on a 2005 Taco.

I think this time around, I will change the thermostat before it falls out, or just buy a new truck when the thermostat goes out... depends on finances :=)

 

[JHZR2]

you put 75k on a truck in one year??? OUCH!

I doubt youll need to do a dozen drains or even flushes putting that mileage on so fast...

JMH