Coolant Change Procedure '07 Freightliner Chass

[hugh37]

Need to change coolant this weekend. Have the supplies, but need help
with the procedure. I gather the radiator cap I need to remove is actually
the cap on the coolant recovery tank? I find a petcock valve on the bottom rear of the side radiator... is that what I open to drain all the old
coolant or must I remove hose(s)? And, to empty the recovery tank, do
I remove a hose attached to it, and should I remove the tank itself and clean it? It's my guess that replenishing with new coolant is done by pouring it into the recovery tank. Correct? I'd much appreciate any help as to how to the proper procedure. Thanks, Hugh.

[bdaball]

Originally Posted by hugh37

Need to change coolant this weekend. Have the supplies, but need help
with the procedure. I gather the radiator cap I need to remove is actually
the cap on the coolant recovery tank? I find a petcock valve on the bottom rear of the side radiator... is that what I open to drain all the old
coolant or must I remove hose(s)? And, to empty the recovery tank, do
I remove a hose attached to it, and should I remove the tank itself and clean it? It's my guess that replenishing with new coolant is done by pouring it into the recovery tank. Correct? I'd much appreciate any help as to how to the proper procedure. Thanks, Hugh.

Hugh37,
Welcome to IRV2. Rather than attempt to answer your question I might offer two suggestions.

1) Call 1-800-FTL-HELP 24/7. There are freightliner personel there to answer such questions. Be sure to have your serial number when you call and they will be able to recognize your chassis configuration and willing to help.
2) Jump in on the Wednesday evening Freightliner chat room right here on IRV2. Every Wednesday at 9 PM EST there will be several Freightliner owners on line. Some more experienced than others. Topics vary from night to night but a great bunch of guys. Most of the guys have "Been there-Done that"......

[henderson]

Originally Posted by hugh37

Need to change coolant this weekend. Have the supplies, but need help
with the procedure. I gather the radiator cap I need to remove is actually
the cap on the coolant recovery tank? I find a petcock valve on the bottom rear of the side radiator... is that what I open to drain all the old
coolant or must I remove hose(s)? And, to empty the recovery tank, do
I remove a hose attached to it, and should I remove the tank itself and clean it? It's my guess that replenishing with new coolant is done by pouring it into the recovery tank. Correct? I'd much appreciate any help as to how to the proper procedure. Thanks, Hugh.

It's a bit more complex than that, you have to drain the heater hose and core in the front, flush the system and refill with distilled water and antifreeze. This is the quick version, but you get the point, it's not as easy a changing antifreeze in a car. Call Freightliner and they can give you the step by step. PS if you haven't changed the T-stats in the past 3 years it's a good time to tackle that also

[rvarner]

Originally Posted by henderson

It's a bit more complex than that, you have to drain the heater hose and core in the front, flush the system and refill with distilled water and antifreeze. This is the quick version, but you get the point, it's not as easy a changing antifreeze in a car. Call Freightliner and they can give you the step by step. PS if you haven't changed the T-stats in the past 3 years it's a good time to tackle that also

Thought the T-Stats every 3 years were just for a Cat engine?
Richard

[Pigman1]

I did a swap out on the antifreeze to go to the long life OAT coolant. Just pulled the lower hose off the side radiator and let it drain. Refilled with tap water and ran it till hot without the cap, and heater on full hot. Drained and refilled with distilled water and ran again, and drained. Refilled a third time with distilled and drained. Then put in 6 gal of fresh antifreeze concentrate (half the cooling system volume) and refilled to full line with distilled water. Checked a few times and refilled with distilled water as the trapped air was naturally flushed out. A check with a refractometer, and freeze temp was right where it should have been.

[jesilvas]

With any coolant flush, you should drain as much as possible first. Then you can flush with a hose to get a lot. Then you alternate between filling with water and draining to get a lot of the coolant out. Then you need to do distilled water flushes. Do you want calcium building up on your system? No. Do that quite a few times, depending on system capacity. Then drain it a final time, refill with HALF the capacity in CONCENTRATE coolant. Then top off, and keep topping off, with distilled water. That is the only way to yield a 50/50 mix.

[Mr_D]

Here's an article that Brett Wolfe wrote for the CAT owners club:

I just changed out my coolant to Caterpillar ELC and replaced all water hoses and belts. Thought I would share the experience.
To my knowledge no chassis/coach maker is using ELC—so all are “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 (we check the SCA concentration in all coaches at Cat RV Club Rallies). When either the time lapses (time starts when coolant 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 Caterpillar ELC 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.

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. I catch it in 2 Rubbermade 10 gallon storage bin lined with black trash sacks so I do not even get them dirty. 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 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 for switching types of coolant, add a Cooling System Cleaner such as Cat Fast Acting Cooling System Cleaner 4C4611. Follow 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 what comes out is 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. My cooling system is 18 gallons, so I added 9 gallons of Caterpillar ELC CONCENTRATE (119-5150) (plus one for overflow container). Top off with distilled water to achieve your 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.