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Old 09-26-2021, 04:25 PM   #1
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Join Date: Apr 2019
Location: Santa Maria, CA
Posts: 15
Need Coolant

So I own a 2015 4037 Ventana, and I checked the level of my coolant and to me it looks low. So I tried just to remove the fill (Radiator us old timers ) cap, but was unsuccessful, the cap would rotate to first release, but no farther, I did not want to take a wrench to it, worried I might break something I shouldn't.

My two questions are, 1. is there a secret to removing the cap and 2. if I need to add coolant, ( I have told we need a specific type) what do I add. Ventana is running the I6 on a freightliner chassis.

Thanks in advance,

Les Wood
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Old 09-26-2021, 07:06 PM   #2
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The caps are a pain on most rigs. Once you get it loose to the point you have it, you need to press down on the cap while continuing to turn it counter clockwise. Don’t take a wrench to it. As far as what coolant, there are general coolant that are compatible with Diesel engine coolant types. I drained, flushed and replaced it all when I serviced mine last.
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Old 09-26-2021, 07:20 PM   #3
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If you have resovior.. just goes in there.. rarely do you need to remove cap.. that is why its frozen on tight .. but if you tried above... get it as far open as you can.. then put paper towels all around and spray penetration oil all under side of cap.. do several times.. that's why all the paper towels.. to catch over spray and dipping... you don't want penetration oil all over where it should not be.. wait 2 to 6hrs.. spray a lot.. then try.. make sure you clean up cap and radiator top with wire brush.. then use some grease.. I like the super lube.. it's clear and water resistant.. but any kind will do.. make sure you get under side of lip of radiator.. that is where the metal on cap corroded to under side of lip.. do cap too.. i clean rubber gasket and lube that up too and the mating surface of radiator.. good luck and let us know what you did and maybe better members then me will help you. Oh I use PB. Blaster.. it dissolves rust.. but what ever you have on hand..
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Old 09-26-2021, 08:04 PM   #4
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Spartan Chassis
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Location: Manitoba, Canada
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Originally Posted by leswood View Post
. . . . the cap would rotate to first release, but no farther, Les Wood
When I replace my expansion tank, I had the same problem with the cap being a bear to get off. What it did was take a file to those first stop points on the filler neck. I filed them down just enough that they still engaged the cap but required less down pressure on the cap for opening. Works slick and the stop points still serve their purpose.
2005 DSDP 4024, Cummins ISL 370, Spartan MM Chassis / 2018 Ford Taurus, Roadmaster Base Plate, Aventa LX Tow Bar, RVI 2 Brakes / 1996 Mariah Shabah Z210 - 5.7L Alpha 1 Gen 2
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Old 09-26-2021, 08:19 PM   #5
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I had a 2015 Ventana. The coolant overflow tank cap (which is like a radiator cap) is removed by turning counter clock wise. After about 1/4 turn you will have to press down on the cap and continue to turn.

My coach had coolant that required SCA and therefore SCA testing and from time to time Fleetguard DCA4 coolant additive . I suspect your coach has the same type coolant unless somebody has changed it. I used Prestone Command HD SCA Coolant. You can get the Fleetguard Coolant Analysis Test Kit # CC2602A and the DCA4 on Amazon or a local truck repair shop.
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