Engine coolant

Topic: Engine coolant (Read 1717 times) previous topic - next topic

Engine coolant

July 21, 2015, 02:08:47 pm

When I moved from the first campground to the next last week, I checked all the engine levels before starting the engine. All seemed well. The coolant level in the sight glass was about half way. I stopped to fuel up around 6 miles into the drive and noticed some liquid under the engine but didn't see anything leaking. Thought it might have been there already. Drove 35 miles to new site, leveled and shut down. While looking around today, there is no water showing in the sight glass.

What type of antifreeze do I need? Should it be over the glass? How much should be in the overflow? What else am I missing? Did some searching on forum and Bary's site but not sure.

Larry

Re: Engine coolant

Reply #1 – July 21, 2015, 02:21:37 pm

Identify what color your coolant is. Any records of changing it? Match colors until you find a leak and then possibly do a drain and refill. Make sure the coolant filter is compatible with the coolant you are using if you change it.

Check the hose to the catch tank at the radiator fill tank. Ours had de-soldered and leaked from there. No joy here, check the radiator tank for leaks where it bolts together. Some engines like Detroits can leak from the back (drive) side of the water pump and are hard to see where the leak is. If the coolant level is too low, the coolant level sensor located below the sight glass may shut the engine down or not allow it to start. Keep the catch tank level between the marks when cold. 50-50 mix works the best.

I was disappointed when I went to the Detroit Diesel Service Center in Sacramento and asked what coolant they recommended. The shop foreman said they just buy any green stuff that is available and put it in.

Re: Engine coolant

Reply #2 – July 21, 2015, 03:05:52 pm

"I was disappointed when I went to the Detroit Diesel Service Center in Sacramento and asked what coolant they recommended. The shop foreman said they just buy any green stuff that is available and put it in. "

I was told the same thing last week at TN RV. The tech was trained by FT and has been working on them for 15 years.

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Re: Engine coolant

Reply #3 – July 21, 2015, 03:20:03 pm

Pierce,

Thanks for the quick reply. The coolant is green. The PO hasn't given me the maintenance records. Said that they were scattered throughout his files along with the fleet of trucks he has. Would try to get them to me. I'll snoop around looking for a leak once I get more antifreeze in it. Nothing is obvious, no water under the engine where we parked.

Not reassuring on what antifreeze to buy from your and Jeff'so account 😠

Keep the info coming.

Larry

Re: Engine coolant

Reply #4 – July 21, 2015, 05:39:27 pm

Larry,

If you do not/can not find out what is in there, strongly suggest you just use distilled water. Even a gallon will not seriously dilute the coolant you have in there-- much better than taking a chance on contaminating with a coolant not compatible with what is in there.

Then, TEST IT. Here are the test strips I use-- will have them in Madison at the Caterpillar Maintenance Seminar I present and then at the Diesel RV Club Meeting. 4 individually packaged test strips for $5. They are designed for "low silicate with added SCA for diesel coolant"(usually green), not the newer generation (usually not green) OAT-based coolants.

They test for: SCA concentration, freeze point and pH.

SCA is used up as it protects the cylinder liners and must be replenished! Again, this is with the "regular" green coolant, not new generation OAT-based coolant.

Re: Engine coolant

Reply #5 – July 21, 2015, 10:40:54 pm

One place to look for a leak is in the Aquahot. There is an elbow there that is prone to pinholes and losing coolant.

Re: Engine coolant

Reply #6 – July 22, 2015, 08:06:38 am

Brett and John,

Thanks, I will look at the aqua hot and find some test strips. Digging into the aqua hot is on my list of things to find. I have noticed a smell of diesel in the storage bay. The electric heating element in the aqua hot doesn't appear to work. The diesel burner does great.

Larry

Re: Engine coolant

Reply #7 – July 22, 2015, 09:25:13 am

Search for "spike45" (Gary Spires) both here and over at iRV2. He is a retired Cummins Fleetguard Field Engineer and has provided a wealth of information on diesel-engine coolants.

Re: Engine coolant

Reply #8 – July 22, 2015, 10:10:50 am

Bottom line: If you do not know how old the coolant is or what kind it is, CHANGE IT. It is a LOT less expensive to change coolant than to loose a radiator due to acidity or cylinder liners due to lack of SCA/proper coolant.

Regular low silicate for diesel with added SCA has a life expectancy of 3-4 years.

The new OAT-based coolants have a life expectancy of 6-7 years.

Re: Engine coolant

Reply #9 – July 22, 2015, 05:31:38 pm

Is it safe to say that you can change from SCA to OAT with a complete flush? Besides aging, any other advantages of one over the other?

Larry

Re: Engine coolant

Reply #10 – July 22, 2015, 05:42:13 pm

Yes, with a complete flush you can go from one type to the other. And, many Foretravels came from the factory with long life coolant-- many used Texaco's product.

Other advantages are zero testing and zero adding of anything unless you drive over 300,000 miles before changing.

Here are step by step instructions on changing coolant-- time consuming, but very low tech: ***Changing Coolant-- A Step By Step Description***

Re: Engine coolant

Reply #11 – July 22, 2015, 05:59:44 pm

Any guesstimates on capacity of 98 320 cooling system ?

Re: Engine coolant

Reply #12 – July 22, 2015, 06:15:25 pm

Thanks Brett, once again, you are the man.

Larry

Re: Engine coolant

Reply #13 – July 22, 2015, 07:52:04 pm

Quote from: TAS69 – July 22, 2015, 05:59:44 pm

Any guesstimates on capacity of 98 320 cooling system ?

Tom,

On our '97 it takes 16 gal total, a '98 should be close to the same.

Pamela & Mike

Re: Engine coolant

Reply #14 – July 22, 2015, 11:10:36 pm

Add RMI-25 Cooling System Treatment to your system. Just pour it in and drive. pc

Re: Engine coolant

Reply #15 – July 23, 2015, 07:40:06 am

Quote from: pocketchange – July 22, 2015, 11:10:36 pm

Add RMI-25 Cooling System Treatment to your system. Just pour it in and drive. pc

I see no good reason to add anything like that to the cooling system. Use a good coolant designed for diesel engines, such as Final Charge Global, and the system should perform quite well.

Re: Engine coolant

Reply #16 – July 23, 2015, 08:41:10 am

I agree with David. Would not use any additive that may or may not be chemically compatible with the coolant in your system.

And, when a product says it cleans the cooling system, I am even more leery.

Re: Engine coolant

Reply #17 – July 23, 2015, 12:44:13 pm

Since parking and leveling a week ago, the rear air bags have maintained nearly full height to keep level, so I crawled under the radiator (without safety stands ) to see what I can find. It appears to have a leak down the back side of the radiator where the bolts are going up the rear side of the radiator.

In searching the forum, several have tightened the bolts, with caution, and /or added Barry Stop leak. I will get my tools out of storage and try tightening. Judging from the paint peeling I don't think that it is a recent development. It's dripping a drop every 30 seconds or so. Parked on gravel so I didn't see anything.

Does the fan shroud need to be removed? For those that tightened and used stop leak, have you had any problems since. If I add stop leak and distilled water and stop the leak, if I then do a coolant change, will I need to add more stop leak?

As always, thanks for the great help.

Larry

Re: Engine coolant

Reply #18 – July 23, 2015, 12:49:54 pm

Quote from: wolfe10 – July 23, 2015, 08:41:10 am

And, when a product says it cleans the cooling system, I am even more leery.

If a product cleans a closed system, then where does the dirt go? <grin>

Re: Engine coolant

Reply #19 – July 23, 2015, 01:18:12 pm

Quote from: D.J. Osborn – July 23, 2015, 12:49:54 pm

If a product cleans a closed system, then where does the dirt go?

From the product FAQ (FAQ | RMI-25)

Question: What happens to the deposits that RMI-25 has dissolved?
Answer: The rust, mineral, and other deposits become a soft floating harmless material. These deposits are purged from the system into the coolant recovery tank. On large diesels the deposits are trapped in the coolant filter. Where no recovery tank or filter is used, it may be necessary to drain the radiator.

Re: Engine coolant

Reply #20 – July 23, 2015, 03:31:29 pm

Just got back from town picking up the test strips I ordered at NAPA. Picked up 3 gallons of distilled water to put in radiator, not knowing how low it was. After 3 quarts the level is at the top of the site glass. Let's me know that I didn't run to low or hot. I feel like I just dodged a bullet

I'll get my tools out tomorrow and try tightening the bolts. Hopefully this will stop my leak.

Larry

Re: Engine coolant

Reply #21 – July 23, 2015, 07:35:43 pm

Larry,
It sure would be good to make up some safety stands for this job, both for safety and working room. If you can't get any steel ones made now, just go to Home Depot and have them cut a 4X4 into four 11" or 12" pieces.

If your radiator is like mine you will have to hold the bolt head when you tighten the nut. Some of those babies are real hard to get at. I used a couple of long extensions and a wiggle. Don't reef on them. Just give them a little twist. Good luck.
jor

Re: Engine coolant

Reply #22 – July 23, 2015, 08:10:33 pm

The coolant tank should be filled to the radiator cap, not just the the sight glass, then the overflow tank filled to the cold level when the engine is cold. If you change the coolant, you may very well have to add Barr's Leak again, but don't do it unless a leak recurs.

Re: Engine coolant

Reply #23 – July 23, 2015, 08:30:25 pm

Agree, I had to use the Barrs Leak on my original radiator, but with the new radiator & some hoses, I have no leaks yet.

Re: Engine coolant

Reply #24 – July 24, 2015, 07:55:21 am

Jor, I agree on the stands. I worked for to long safely to try something dumb now.

Amos, thanks for the tip on the swivel. I will pick one up. I broke the last one several years ago and didn't replace it. I only put in up to the site glass for now so I can monitor the rate of loss. I will be sure to fill all the way once I get it stopped.

Larry

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