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-   -   Diesel Pusher Owners Beware - Coolant System (https://www.forestriverforums.com/forums/f4/diesel-pusher-owners-beware-coolant-system-82001.html)

gmcnitt 05-13-2015 08:18 PM

Diesel Pusher Owners Beware - Coolant System
 
I have a 2009 Charleston with a Cummins ISL 450hp engine, rear radiator. The last trip I noticed the coolant reservoir needing about a gallon a day (roughly 400 miles). Tested pressure, no leaks, oil is fine. I have been adding regular tap water, figuring I would take care of it when I returned....BIG mistake. The coolant in these units does a lot more than cool....I have spent the last few weeks researching all the options, etc....but I never knew so never did anything to this units cooling system. Every 6 months you are suppose to check the SCA levels, and adjust as necessary. This basically keeps the engine from blowing holes in the wet sleeve liners of the engine and requiring a rebuild in 100k miles due to a cavitation issue with these heavy duty diesel engines. Keep the levels all fine, and you are good, ignore them like I did and you could run into expensive repairs...just do a few searches for coolant systems for diesel engines, lots of data available.

I called Freightliner (FL) first, inquiring about going to the new OAT ECL coolants, these do not require testing, and are better for the engine, better heat transfer, better lubrication, and last longer. They told me the low coolant sensor would not function if I switched coolant types...(this made no sense to me so I called Cummins). They laughed when I told them what FL said. They told me just flush the system with distilled water and fill it with 50/50 ECL and it would be a lot more efficient, and the coolant sensor would be just fine.

I plan on doing it this weekend...drain, fill with tap water, drain, fill with distilled water twice, drain, then do the final fill with the new ECL coolant. Right now I am leaning towards Final Charge.

Anyone else do this? Thanks!

Blackrock 05-13-2015 08:31 PM

Save time and money and just flush with tap water and skip the distilled water step. I am a master mechanic for a large fleet and we use SCA treatment cartridges and just drain and refill entire coolant every two years. We use test strips to check SCA levels at every oil change and change the SCA treatment cartridge annually.
If you are losing more than a gallon of coolant per day you have more problems than a flush and refill will fix I'm afraid.
https://www.donaldson.com/en/engine/s...ary/000376.pdf

gmcnitt 05-13-2015 08:38 PM

One of the many links I found, thanks.......right now I'm leaning towards the OAT ECL. I would rather spend a little more and not worry about it......

But you have me thinking....losing a gallon a day, if it were all water in there, could it be boiling over? I would hate to put this expensive stuff in and lose it all......I searched from front to back, no leaks anywhere, radiator cap tests good, pressure tested the system to 20 psi, held no problem......oil is clean......so I was hoping it was due to it being all water and just boiling out....any possibility?

Maybe I need to take the standard route to see if it holds the fluid first.....

Blackrock 05-13-2015 10:11 PM

With problem vehicles I add a bottle of stop leak and it usually helps.
https://www.napaonline.com/Catalog/Ca...T11_0424510082
Plain water with a 20psi cap won't boil out until 226 degrees or so. Most caps are 16# these days.

TGR 05-14-2015 04:20 PM

If cavitation is the cause of your coolant loss, I would be very concerned. Perhaps Blackrock could describe additional observable symptoms for engines where cavitation has eroded the cylinder walls enough to cause coolant loss, e.g., exhaust color, oil or coolant contamination.


Of course, it could be a head gasket that is leaking. Have it checked out by a competent diesel mechanic for peace of mind and to avoid additional problems. The level of coolant loss you have it too much to ignore.

Bubbamace 05-14-2015 06:35 PM

Quote:

Originally Posted by gmcnitt (Post 862641)
I have a 2009 Charleston with a Cummins ISL 450hp engine, rear radiator. The last trip I noticed the coolant reservoir needing about a gallon a day (roughly 400 miles). Tested pressure, no leaks, oil is fine. I have been adding regular tap water, figuring I would take care of it when I returned....BIG mistake. The coolant in these units does a lot more than cool....I have spent the last few weeks researching all the options, etc....but I never knew so never did anything to this units cooling system. Every 6 months you are suppose to check the SCA levels, and adjust as necessary. This basically keeps the engine from blowing holes in the wet sleeve liners of the engine and requiring a rebuild in 100k miles due to a cavitation issue with these heavy duty diesel engines. Keep the levels all fine, and you are good, ignore them like I did and you could run into expensive repairs...just do a few searches for coolant systems for diesel engines, lots of data available.

I called Freightliner (FL) first, inquiring about going to the new OAT ECL coolants, these do not require testing, and are better for the engine, better heat transfer, better lubrication, and last longer. They told me the low coolant sensor would not function if I switched coolant types...(this made no sense to me so I called Cummins). They laughed when I told them what FL said. They told me just flush the system with distilled water and fill it with 50/50 ECL and it would be a lot more efficient, and the coolant sensor would be just fine.

I plan on doing it this weekend...drain, fill with tap water, drain, fill with distilled water twice, drain, then do the final fill with the new ECL coolant. Right now I am leaning towards Final Charge.

Anyone else do this? Thanks!

Just read about this exact same thing in Motor Home magazine.:trink39:

67cudafb 05-14-2015 08:01 PM

May be a crack in reservoir is cracked or a cracked hose. I would fill it and let it sit and not start and see if level drops.

gmcnitt 05-14-2015 08:36 PM

I always do my own work when out of warranty, so I'll figure it out eventually. For next weeks trip a flush and fill with OEM coolant is what she is getting and we will go from there. Also going to do an oil and filter change. With only 30k miles I doubt its a cavitation issue, that takes 100k abused miles from what I have read. The engine has never over heated, and the oil is clean and water free.

Ditchooker 05-16-2015 01:52 AM

If it is EGR equipped, the older EGR coolers have been prone to cracking internally and it will start burning the coolant doing some nasty stuff to the DPF. I work in a fleet shop that runs alot of ISL's, and I remember reading a service bulletin that Cummins has an updated EGR cooler that came out a while ago

RoamingEngineer 05-16-2015 08:56 PM

I was losing coolant on one trip and found that the coolant was leaking in the nose of the vehicle where the coolant line attached to the heater block.

I was losing a significant amount and showed no signs of it until I noticed the top of the generator was a little wet.

gmcnitt 05-20-2015 09:39 PM

Wish me luck, I have flushed and refilled the coolant system with standard antifreeze and distilled water, as well as added the CSA additives. I also did an oil and filter change as it was due anyway. Tightened all hose clamps on all ends, front back, etc.....now I just hope for the best....leaving Friday for a short 5 hour trip to San Antonio.......thanks for all the things to check.


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