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Old 12-10-2022, 11:45 AM   #1
Mid Atlantic Campers
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Bad coolant report L9 450

I have a coolant report (still waiting on the engine oil report) for a 2017 Dutch star. I don't own the coach, this an inspection report of fluid taken. The coach has 45,000 miles. I'm sharing to see what others have done or what issues current owners have with Cummins regarding coolant. I hope the oil report has no issues.

Engine (as reported) L9 450hp side radiator. report below
Attached Files
File Type: pdf Coolant report 09Dec2022 Cummins .pdf (132.4 KB, 23 views)
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Old 12-10-2022, 05:38 PM   #2
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Unfortunately, it appears the coolant wasnít maintained. Not sure if the chassis is freightliner or powerglide but freightliner uses coolant that requires maintenance of the SCA level. When we were looking at coaches, we couldnít find a single coach where there were records of the coolant maintenance. The one we bought, a 2015 Phaeton, came back from JG with a bad coolant report as well. The iron was high, indicating likely liner pitting. I told the dealer and sent him the report along with a couple of articles on the criticality of coolant maintenance.

I then found a couple of guys on line that had similar situations and had flushed and changed the coolant and have been good so far. I called the dealer and was going to tell him we were going to pass on the coach. We had already come to agreement on a deal based on a good inspection result. They said they would flush and change the coolant at the local Cummins facility. They then offered to reduce the price of the coach by half of a rebuild cost so the risk was part theirs and part mine. I told them to have the Cummins dealer change the crankcase filter and save it for my inspection since any coolant seepage into the oil would show up on the filter as white sludge (the dealer had already done an oil change).

Cummins swapped the coach over to the Fleetguard OAT coolant when they did the flush to get rid of the SCA maintenance requirement and because thatís what Cummins recommends.

I have since put 20K miles on the coach but have also swapped the coolant one more time after a year without a flush to ensure all flushing chemicals were out.

You have to go with what you feel comfortable with. However, with the economy slowing and RV sales decreasing rapidly you may be able to use this bad report to cover any future repairs that result from the poor maintenance. On the other hand, there could be a lot more to choose from in the future due to economic conditions.

We had looked for two years and never found a coach with maintenance records or proper coolant maintenance so we decided to roll the dice.
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Old 12-10-2022, 07:01 PM   #3
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I appreciate your candor with sharing your experience. This coach also lacks maintenance records and it is being sold privately, which is disappointing. I have a good feel about the integrity of the seller and the coach presents its self very well, but as you alluded, the markets changing, and my offer/purchase will possibly seem generous in the not too distant future. That said, you can wait forever and time will wait for no one. I will continue to solicit advice/experiences from those who have had a similar experience.
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Old 12-11-2022, 07:06 AM   #4
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Does this engine have a coolant filter??? Mine does but I know that at some point Cummins did away with this.

I bought my coach in 2008 with no maintenance records, it was a repo, but from the condition of the rig it appeared like it was well taken care of.
I checked the coolant with test strips and changed the coolant filter every ~2 years. But I lost confidence in my ability to read the strips, actually got a quote from the local Cummins shop to do a flush and change but the manager recommended I get the the coolant tested, this was in 2015. My guess was that the coolant was original so it was ~14 years old. But the coolant analysis came back great, as if it was new.

So for that coolant to show that condition there must be something seriously wrong. I guess you could take a chance on it and spend to get some sort of good warranty but there is a risk. Either way the engine needs to have a good flush and new coolant added.

I late 2015 (yes, right after I got a good coolant analysis report back) road debris took out my radiator. Got a new radiator installed and Cummins used the ES Compleat blue coolant. Manager recommended this and said this would last the life of the rig.
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Old 12-11-2022, 11:20 AM   #5
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I bought a 2012 Dutch Star fall of 2021 with about 60,000 miles.
My turbo VGT controller failed in spring of 2012, replaced. Failed again after a few days and a few hundred miles. Replaced under Cummins warranty and then failed again. 3rd Freightliner shop finally found source of problem. Leaking frost plug on top of turbo housing, under the controller. Coolant vapour was taking out the circuit board in the controller. The shop also found severe corrosion on banjo bolts
for coolant lines to turbo. Coolant especially in big Diesel engines becomes very corrosive over time. Very bad for numerous parts including EGR cooler.
Donít cheat on your coolant
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Old 12-11-2022, 02:14 PM   #6
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Thanks for the comments. I don't own the rig at this point. If there is something that needs to be replaced (beyond the coolant itself) then I want it either done pre purchase or will talk to the seller to come up with a reasonable solution. Is it serious or just normal for its age/milage? If readers on this board with diesels have similar issues with coolant at half life, I'd like to know.
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Old 12-18-2022, 11:29 AM   #7
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The coolant analysis is alarmed by the copper levels. However, the copper levels are zero. They probably meant to comment on the aluminum levels. Perhaps you can point this out to them and they'll revise their report to further assist with clarifying the contamination issue(s).
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