What fluid goes in overflow container off the radiator?

Topic: What fluid goes in overflow container off the radiator? (Read 721 times) previous topic - next topic

What fluid goes in overflow container off the radiator?

July 01, 2016, 01:59:10 pm

The plastic container overflow has about 8 oz of fluid. Should I add to that and if so what is the recommended fluid?
Thanks

Re: What fluid goes in overflow container off the radiator?

Reply #1 – July 01, 2016, 02:18:10 pm

That is your coolant overflow container and you should put in the same coolant that is in your cooling system. Mixing coolant types can cause problems and cost you $$$. If you have service records, it should state what type of coolant is in the cooling system.
If not, is it time for a cooling system service? Maybe you want to flush and fill the system with Extended life coolant for heavy duty diesels?

If you are not sure, have it checked out by a service tech before adding.
Hope this helps.

Re: What fluid goes in overflow container off the radiator?

Reply #2 – July 01, 2016, 02:18:45 pm

This has been covered many times, it's amazing the number of different substances that are used in various cooling systems. If the coolant is just a "tad" low, add distilled water to bring it up to "low". Check labels or files to see what coolant is suggested.

Re: What fluid goes in overflow container off the radiator?

Reply #3 – July 01, 2016, 02:26:01 pm

I'll see if I can find mention of coolent being serviced. If not I'll add it to the list. Wasn't sure how much fluid should be in there.

Re: What fluid goes in overflow container off the radiator?

Reply #4 – July 01, 2016, 02:31:12 pm

There should be a "cold" and "hot" mark.

Hot mark 2/3 full.
Cold mark around or a little less than 1/2 full.

As suggested, if you do not know what coolant is in there, just add distilled water.

BUT remember, you have a LINERED engine. Neglecting coolant can result in pitted cylinder liners and very expensive engine repairs!

Re: What fluid goes in overflow container off the radiator?

Reply #5 – July 01, 2016, 02:33:13 pm

Quote from: goldbehen – July 01, 2016, 02:26:01 pm

Wasn't sure how much fluid should be in there.

Is there not a "cold/hot" marking on the overflow container?

Re: What fluid goes in overflow container off the radiator?

Reply #6 – July 01, 2016, 02:42:14 pm

It's funny, being a slow-poke writer, how by the time I can post, SOMEONE ELSE has chimed-in with the same (and better) response! At least the OP knows, we're all on the same page!

Re: What fluid goes in overflow container off the radiator?

Reply #7 – July 01, 2016, 04:37:48 pm

So I'm seeing 3 choices here.

1- distilled water
2- 50/50 mix of existing coolant type and distilled water.
3- coolant concentrate. ( which evaporates faster, coolant or d water ? ).

My guess # 2

Re: What fluid goes in overflow container off the radiator?

Reply #8 – July 01, 2016, 04:44:55 pm

Not sure why you guys don't have a sticker like this: Depending on our engines, a sticker would seem to me, " de rigueur".

Re: What fluid goes in overflow container off the radiator?

Reply #9 – July 01, 2016, 05:30:56 pm

Quote from: Bob & Sue – July 01, 2016, 04:37:48 pm

So I'm seeing 3 choices here.

1- distilled water
2- 50/50 mix of existing coolant type and distilled water.
3- coolant concentrate. ( which evaporates faster, coolant or d water ? ).

My guess # 2

OK, there is no simple answer, but here goes:

If you know what coolant is in there, AND you have tested it, use either distilled water or that coolant to bring you to a 50/50 mixture (freeze point -34 degrees F). If "regular low silicate coolant for diesel with added SCA/DCA, test SCA/DCA at the same time and bring it to proper concentration (generally 1200 PPM)

If one of the new generation OAT-based coolants, no SCA/DCA to test or add.

If you have not tested is, but know what coolant is in there, ASSUMING THAT IT ALREADY HAS A 50/50 MIXTURE, add half of the same coolant/half distilled water.

If you don't know what coolant is in there, add distilled water.

If you don't know what coolant is in there and "regular coolant for diesel with added SCA" over 3 years old or OAT based coolant over 6 years old CHANGE IT NOW AND CHANGE IT PROPERLY. Will put proper way in a separate post. It is time consuming, but VERY low tech. Said another way and shade tree mechanic will likely do a better job than any shop (because a shop will not/can not take the time to do it correctly.

Re: What fluid goes in overflow container off the radiator?

Reply #10 – July 01, 2016, 05:32:33 pm

Cooling System 101, from an article I wrote years ago for the FMCA Magazine:

I just changed out my coolant and replaced all water hoses and belts. Thought I would share the experience.
To my knowledge all RV manufacturers use a "low silicate coolant for diesels" with included or added SCA. Coolant needs to be changed per manufacturer's instructions (usually every 3 years). Additionally the SCA, pH and freeze point need to be checked on regular intervals using SCA test strips and SCA added as needed. The test strips are inexpensive and easy to use. When either the time lapses (time starts when coolant is installed in cooling system, NOT when purchased) or testing reveals an out-of-line conditions like pH or freeze point, it is time to change it. You can avoid all the testing and SCA adding, and go to 6 year change intervals by going to an Extended Life Coolant and get better cooling system protection as well. Whichever coolant you choose, most of the steps are the same. The job is reasonably time consuming TO DO RIGHT, but low-tech.

First step is to determine your total cooling system capacity. Your chassis maker or coach maker, not your engine manufacturer is the proper source. Then buy enough coolant (concentrate, not pre-dilute) to make up 50% of that volume. If going back with a coolant that requires additional SCA, purchase that as well. Also purchase 1.5 times system capacity of distilled water for a final flush plus final fill (50%). Also a good idea to change the engine thermostat and thermostat gasket as these are a wearing component and it involves very little more work while you are there. I know Caterpillar recommends thermostat (they call them regulators) every 3 years.

Turn dash heater to full hot for the rest of the procedure—fan off. With the engine cold or at least cool, drain coolant. On some, there is a drain cock. On others, pull the lower radiator hose. Two Rubbermade 10 gallon storage bin lined with black trash sacks so they don't get dirty work well. At the end of the whole process, use a coffee can and funnel to pour old coolant into new coolant/water containers for recycling. Our city maintenance shop recycles coolant for free.

Refill cooling system with tap water. IMPORTANT: Be sure to remove any air lock from the thermostat housing. Some systems have a hose set up for this—on ours I just loosen the coolant line to the air pump and bleed the air out. Allow engine to warm up (using the cruise control to select idle speed of 1,000-1,100 speeds this up). Run for about 10 minutes at regular temp. If the temp gauge does not rise as normal, you likely have an air block and need to bleed the thermostat housing. Allow engine to cool 20-30 minutes and drain again. Repeat until the effluent color is clear.

At this point, if this is the first coolant change on a 2-3 year old coach and you are not changing coolant brands/types, skip right to "Last rinse". For older systems or when switching types of coolant, add a Cooling System Cleaner. Follow the directions. Run, allow engine to cool, drain and again flush until effluent is clear. The flushing is markedly sped up by pulling off the heater hose (usually 5/8" to ¾" lines) going to dash heater/motor-aid water heater, etc from the water pump. Put a hose nozzle in the hose and let it run until it comes out clear. Run the engine to temperature at least once with tap water.

If your hoses are over 3-4 years old, this is a good time to change them as well (before last rinse). Same for thermostat(s).
Last Rinse is with distilled water. At $.62/gal at Walmart, it is silly to skip this step and leave your system full of high-mineral content water (there will be several gallons of residual water that you can not easily remove). Run engine for 10 minutes after getting to operating temperature. Cool and drain. Also drain and flush your coolant overflow container and refill with new coolant/distilled water.

Add the proper amount of Coolant CONCENTRATE (NOT PRE-DILUTE) to make 50% of cooling system capacity. So for a cooling system with 20 gallons capacity, add 10 gallons of Coolant CONCENTRATE (plus 1/2 overflow container capacity). Top off with distilled water to achieve your 50/50 mixture—it doesn't matter if you only have to add 1 gallon or 10 of distilled water, you KNOW you have the proper 50/50 mixture.

This is also a good time to clean the OUTSIDE of the radiator/after-cooler whether you have rear or side radiator. On rear radiator, most if the debris will be on the FRONT of the after-cooler (accessed from under the bed). On side radiators, most debris is on the outside of the after-cooler (side of coach). If it is just dirt, a hose and regular nozzle is all you need. If greasy or oily, use Joy liquid (dish washing detergent) in a spray bottle. Be SURE to rinse it off completely. You need to insure that the perimeter is as clean as the center. Ya, I know it is easier to see the center, but the fan blades "sling" the dirt to the perimeter.

Check belts while you are in there.

Re: What fluid goes in overflow container off the radiator?

Reply #11 – July 02, 2016, 01:47:49 am

Thank you Brett!

Re: What fluid goes in overflow container off the radiator?

Reply #12 – July 02, 2016, 05:23:08 pm

Quite an education. Probably need to add some distilled water and plan to change coolent using the above method. I don't want to be the cause of expensive repairs . Glad I asked about this. As always thanks for the great information.

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What fluid goes in overflow container off the radiator?

July 01, 2016, 01:59:10 pm

Re: What fluid goes in overflow container off the radiator?

Reply #1 – July 01, 2016, 02:18:10 pm

Re: What fluid goes in overflow container off the radiator?

Reply #2 – July 01, 2016, 02:18:45 pm

Re: What fluid goes in overflow container off the radiator?

Reply #3 – July 01, 2016, 02:26:01 pm

Re: What fluid goes in overflow container off the radiator?

Reply #4 – July 01, 2016, 02:31:12 pm

Re: What fluid goes in overflow container off the radiator?

Reply #5 – July 01, 2016, 02:33:13 pm

Re: What fluid goes in overflow container off the radiator?

Reply #6 – July 01, 2016, 02:42:14 pm

Re: What fluid goes in overflow container off the radiator?

Reply #7 – July 01, 2016, 04:37:48 pm

Re: What fluid goes in overflow container off the radiator?

Reply #8 – July 01, 2016, 04:44:55 pm

Re: What fluid goes in overflow container off the radiator?

Reply #9 – July 01, 2016, 05:30:56 pm

Re: What fluid goes in overflow container off the radiator?

Reply #10 – July 01, 2016, 05:32:33 pm

Re: What fluid goes in overflow container off the radiator?

Reply #11 – July 02, 2016, 01:47:49 am

Re: What fluid goes in overflow container off the radiator?

Reply #12 – July 02, 2016, 05:23:08 pm

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