Go Back   iRV2 Forums > MOTORHOME FORUMS > Class A Motorhome Discussions
Click Here to Login
Join iRV2 Today

Mission Statement: Supporting thoughtful exchange of knowledge, values and experience among RV enthusiasts.
Reply
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on iRV2
 
Thread Tools Search this Thread Display Modes
 
Old 08-25-2014, 03:27 PM   #1
Junior Member
 
Join Date: Jul 2014
Posts: 22
Possible wet cylinder cavitation pitting from poor coolant?

We are still in the inspection phase of possibly purchasing an 04' motorhome with a Cummins ISL 400hp diesel with 71k miles. So far we've only received the coolant analysis results. The tests show that the engine coolant was in poor condition if the coolant was originally a conventional low silicate Ethylene/Glycol formula as opposed to an ELC Extended Life Coolants which are nitrate based. The results below show a low level of nitrates which could indicate it may have been changed to a ELC, but the other numbers seem more consistent with a conventional E/G coolant. It also possible it is a mix of conventional and ELC which isn't advised.

On a 0-4 scale with 4 being critical, the overall score was 3. The following are the abnormal results.
Basic testing:
-Color- cloudy dark yellow.
-7.4 ph, (normal- 8-11)
-Nitrate 295 ppm -strip test (normal 800-1200)?
-SCA level 0.6 (normal 1.2 -3 .1)
-Corrosion metals: Copper 13ppm
-Corrosion Inhibitors: Molybdenum 76ppm (normal 1000)?
Everything else was within normal levels.

I've read about how important it is to maintain the coolant condition and SCAs in diesel engines with wet cylinder sleeves due to the possible cylinder pitting from cavitation due to poor coolant which could lead to pinhole formation. Don't know if this is true, but I was told by a service manager that Cat motors were more prone to the pitting than Cummins.

Am I being unduly concerned about the condition of the coolant which might have the potential to cause severe failure?
Of the repair/maintenance invoices reviewed, none show radiator/coolant maintenance so I'm guessing there's a good chance the coolant is the original factory coolant.

A Spartan factory tech advised that the original coolant was an Ethylene/Glycol 50/50 mix. He also said Spartan advises to continue using the same original type of coolant whereas a Cummins factory tech said they like the newer OAT coolants but that either was OK. He also said that the freeze plugs can start leaking from corrosion which can be an indicator of poorly maintained coolant.

This will be our first motorhome purchase and this particular coach has several features that we really like but after not having a chance to test the old oil then receiving the poor coolant tests results we are questioning going forward. Though

Would like to hear from someone that has dealt with this same issue or knows of someone who has.
__________________

__________________
Aurum is offline   Reply With Quote
Join the #1 RV Forum Today - It's Totally Free!

iRV2.com RV Community - Are you about to start a new improvement on your RV or need some help with some maintenance? Do you need advice on what products to buy? Or maybe you can give others some advice? No matter where you fit in you'll find that iRV2 is a great community to join. Best of all it's totally FREE!

You are currently viewing our boards as a guest so you have limited access to our community. Please take the time to register and you will gain a lot of great new features including; the ability to participate in discussions, network with other RV owners, see fewer ads, upload photographs, create an RV blog, send private messages and so much, much more!

Old 08-25-2014, 03:37 PM   #2
Senior Member
 
GaryKD's Avatar
 
Newmar Owners Club
Join Date: Jul 2006
Location: Wellington, Florida
Posts: 12,322
Hi Aurum,
I have not dealt with this issue. For me, I'd pass on this coach. If you do make a purchase, when the coolant is replaced, make sure the rubber connecting hoses are also replaced. I think there are 5 of these connecting hoses. They are about 8" long and connect the coolant pipes to what ever they are connected to.
__________________

__________________
Gary
2005 Newmar KSDP 3910 + GMC ENVOY XUV 37K lbs Moving Down The Road
The Avatar Is Many Times Around The USA
Nobody Knows Your Coach Like Somebody Who Owns One Just Like Yours
GaryKD is offline   Reply With Quote
Old 08-25-2014, 04:03 PM   #3
Senior Member
 
RinkersRanch's Avatar


 
Fleetwood Owners Club
Mid Atlantic Campers
Workhorse Chassis Owner
Join Date: Apr 2010
Location: Locust Grove, Virginia
Posts: 345
RV Coolant

RV Diesel engine coolant article. Here is a link to a great article on the subject. I use to teach Diesel engine maintenance for Caterpillar and this article touches all the important bases on Diesel engine coolant requirements. No, it will not answer the question 'should I buy this coach' but it will explain what is going on in the cooling system and what is required of coolant.
__________________
Wayne, Diane, & Bentley (our 22 lb. alarm system)
02 Pace Arrow 37A-Workhorse, 01 Jeep Wrangler toad.
RinkersRanch is offline   Reply With Quote
Old 08-25-2014, 04:04 PM   #4
Senior Member
 
Steve Ownby's Avatar
 
Join Date: Nov 2008
Location: Cosby, Tn
Posts: 6,396
Quote:
Originally Posted by Aurum View Post
We are still in the inspection phase of possibly purchasing an 04' motorhome with a Cummins ISL 400hp diesel with 71k miles. So far we've only received the coolant analysis results. The tests show that the engine coolant was in poor condition if the coolant was originally a conventional low silicate Ethylene/Glycol formula as opposed to an ELC Extended Life Coolants which are nitrate based. The results below show a low level of nitrates which could indicate it may have been changed to a ELC, but the other numbers seem more consistent with a conventional E/G coolant. It also possible it is a mix of conventional and ELC which isn't advised.

On a 0-4 scale with 4 being critical, the overall score was 3. The following are the abnormal results.
Basic testing:
-Color- cloudy dark yellow.
-7.4 ph, (normal- 8-11)
-Nitrate 295 ppm -strip test (normal 800-1200)?
-SCA level 0.6 (normal 1.2 -3 .1)
-Corrosion metals: Copper 13ppm
-Corrosion Inhibitors: Molybdenum 76ppm (normal 1000)?
Everything else was within normal levels.

I've read about how important it is to maintain the coolant condition and SCAs in diesel engines with wet cylinder sleeves due to the possible cylinder pitting from cavitation due to poor coolant which could lead to pinhole formation. Don't know if this is true, but I was told by a service manager that Cat motors were more prone to the pitting than Cummins.

Am I being unduly concerned about the condition of the coolant which might have the potential to cause severe failure?
Of the repair/maintenance invoices reviewed, none show radiator/coolant maintenance so I'm guessing there's a good chance the coolant is the original factory coolant.

A Spartan factory tech advised that the original coolant was an Ethylene/Glycol 50/50 mix. He also said Spartan advises to continue using the same original type of coolant whereas a Cummins factory tech said they like the newer OAT coolants but that either was OK. He also said that the freeze plugs can start leaking from corrosion which can be an indicator of poorly maintained coolant.

This will be our first motorhome purchase and this particular coach has several features that we really like but after not having a chance to test the old oil then receiving the poor coolant tests results we are questioning going forward. Though

Would like to hear from someone that has dealt with this same issue or knows of someone who has.

I applaud your self education concerning the critical importance of coolant particularly in a wet sleeved diesel. Most buyers are not nearly so knowledgeable.

If it were me I would pass on this one. The coolant may be an indicator of cavitation damage but it's also an indicator of an owner who did not keep up with the maintenance. I'll bet the transmission fluid and filters are OEM also. There are plenty of very well maintained coaches on the market. Keep looking.

The C7 or 3126 Cat which is most often found in motorhomes is not a wet sleeved engine and is not subject to cavitation.


Steve Ownby
Full time since '07
__________________
Steve Ownby
Full time since 2007
2003 Monaco Signature
Steve Ownby is offline   Reply With Quote
Old 08-25-2014, 04:09 PM   #5
Senior Member
 
Dtwallace's Avatar
 
Join Date: May 2014
Posts: 1,143
Aurum,

Not disagreeing at all with GaryKD's caution. How ever I'd like to just add my experience in operating wet sleeve engines in over the road trucking.

In my opinion, and experience, it would be the milage put on that engine during the time the antifreeze in question was in it.

With setting time, not running time, corrosion would occur without the proper protection. However it would take quite a long time to cause damage as it would be more like a surface rust on the block and cylinder liners, in any at all.

Continued operation in that deficient antifreeze condition wound cause a failure of the liners at about the 500K mile area if it was a really bad mix.

The new engines are so robust, that I'd would not be concerned with a low mileage encounter with bad antifreeze where the rest of the engine tests out in perfect working order.

The obvious concern is how you will care for this engine through out it's remaining years.

Suggestions above to replace rubber hoses or other items is cheap insurance against future failure, and you know exactly what you are working with. To go farther, at 71K, for peace of mind go ahead and replace all the drive belts also. Chances are then, you'll never have to replace them again, unless you are never planning to sell this coach. Just my thoughts. Finding the perfect coach is all but impossible. Finding one that you can and are willing to work out minor issues is the start of an adventure.
Best of luck
DTW
__________________
Dtwallace is offline   Reply With Quote
Old 08-25-2014, 04:41 PM   #6
Senior Member
 
Hooligan's Avatar
 
Freightliner Owners Club
Join Date: Apr 2002
Location: Pensacola
Posts: 2,206
It does sound like a mix of coolants.??? Agree with Steve above, good homework.....
Cummins may be the one to ask about the results of the testing
Here is the Cummins Service Bulletin on Coolants. http://www.granlydiesel.com/fileadmi...2__12sep13.pdf
__________________
Hooligan, Pensacola, Fl -U.S. Coast Guard 1956-1985
2016 Thor Siesta Sprinter 24ST diesel
Our Pug "Lily" & "George" the Newfoundland
Hooligan is offline   Reply With Quote
Old 08-25-2014, 05:02 PM   #7
Junior Member
 
Join Date: Jul 2014
Posts: 22
Thanks guys!!!!! Great info! I have more reading/learning to do. I'll update as I find out more. Had I been able to sample the old oil I think I'd have a better idea as to what the best decision would be but I can only go on with what I have.
__________________

__________________
Aurum is offline   Reply With Quote
Reply



Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
DIY Wet Hubs rmcb Monaco Owner's Forum 24 09-25-2014 02:12 PM
Wet Basement!!! Blackcabby Tiffin Motorhomes Owners Forum 13 09-15-2014 09:40 PM
95 Monaco Dynasty Wet Spot on Floor jimwrye Monaco Owner's Forum 3 07-22-2014 07:38 PM
'95 Dynasty Step Slide Air Cylinder Access Pete Miller Monaco Owner's Forum 1 05-25-2014 07:29 PM
Front Disc/Rotor Temp and Master Cylinder Gasket 1969SSCamaro Workhorse and Chevrolet Chassis Motorhome Forum 9 03-19-2014 01:48 PM

» Virginia Campgrounds

Reviews provided by


Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 11:05 PM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.