Rear Radiator Cleaning - A Cautionary Tale!

[Scotty Hutto]

Sharing my embarrassment as a reminder to those folks who have rear radiator coaches… Do a good job cleaning that rear radiator!  There are other threads here detailing the process, but I want to emphasize spraying cleaner on *both* sides of the radiator and rinsing. I thought I had been cleaning my radiator the six years I’ve owned my Dip - it looked really good from the back of the coach, but I’ve never done much cleaning from the front (engine) side of the coach. Shame on me. Fortunately (and I really mean that!) it sprung a leak after 17 years and 102,000 miles.  Wifey said she wanted a new radiator - don’t wait to see if this one can be repaired because if we waited to see if it could be repaired, and then had to order it after they pulled the old one, it could mess up our “big” trip coming up in August. So we ordered a new radiator from Radiator Supply House that arrived last Friday  

MTR Fleet Services in Cumming, GA pulled the radiator this morning and I was floored at what they found.  My coach has only overheated once in the 6 years I’ve owned it, but this is what they found:

Radiator:

Up close…

The entire center of the radiator was completely plugged!  The four corners were all blocked. There was a ring of open area around the plugged center where air could pass. 

Fortunately, my CAC was pretty clean, but will undergo pressure testing, repair if necessary, and cleaning. The squeaky (bearings) water pump is being replaced, a stainless steel Talin Vector surge tank installed, and all new belts and hoses. 

Charge Air Cooler (CAC)

[Steve P]

Scotty - makes me cringe too...  Because I doubt my radiator has been cleaned in the 15 years of its existence.   There have been higher priorities in the 3 years I've had this beast.  Sigh... I guess I need to add this to the list!   When you know the total cost of this project, please add that to the post for the benefit of those of us who are cringing.  Good luck, and I hope you don't find any other issues. It sounds like you are being very thorough.

[jacwjames]

Are you going to have the CAC tested/cleaned.

When my radiator had holes punched in it and replaced I took the CAC to shop to have it clean/tested.  It looked good, didn't really look too dirty and I didn't see any potential problems for leaks.  After a week I called the shop and they said the CAC was bad with lots of leaks.  I was skeptical so I took the time to drive there and have them show me.  They had a large tank they dropped it into with air pressure on it and it looked like a jacuzzi the way it was bubbling.   So the shop sent it off for repair.

[bklaes]

Scotty, This is timely.   I"ve owned my Dip for 7 years and at first it ran very hot, but the Simple Green in a garden sprayer treatment on front and back dropped temps 30 degrees!   (from 207 to 177)   Over the years the temps have crept up, despite me hosing off the rear radiator regularly - from the rear only... a maintenance shortcut. 

Prior to my recent big trip last month, I hosed off the radiator with Simple Green - again from the rear only.  Through the mountains the temps soared.  Check engine and even stop engine light came on as I crept up a mountain.  After a cool down, the ISL400 continued to run fine.   Once home I hosed off the radiator from the inside out and was shocked to see how much dirt came out.  I'm eager to see how the temps do.

[Scotty Hutto]

37 minutes ago, jacwjames said:

Are you going to have the CAC tested/cleaned.

Yes. My CAC is being tested and repaired (if necessary) today. 

[Rikadoo]

I understand about dirty radiators, couple years ago i replaced mine. Same scenario in that i washed mine from the outside, when it started leaking is when i replaced it. I took the advice from some that had done theres, i cut a square hole in the bottom of the shroud then cut a piece of sheet metal to cover it an put a couple screws in it to hold it in place, that way in case i had to get something out i could open it up reach in an take it out. The other was to put two “ball valves” on the heater hose inlet an outlet so if the heater core starts leaking i can turn it off an continue my trip. When i cut my heater hose to install the valves i replaced the hoses on the engine sides so to illuminate the possabilty of the leak on that side of the valve. I am amazed how well the new radiator and the other cooling system parts changed my operating temps, i have not seen it go over 200 since then.

Oh while i was in there i also removed the alternator an had it rebuilt

[Paul J A]

Use a trouble light at night, shine from the engine side of the radiator, and view  the areas that need attention, from the outside . 

[bestins]

How are you getting to the radiator to clean from the inside, or what tools are you using.  Like you I've always cleaned mine from the rear, looking at the front of radiator from the access hole in the bedroom, I don't see a way to really give it a good washing. 

[Gary 05 AMB DST]

I've always been a radiator cleaner believer.  Look at the radiator from inside the MH. Look at the lower right and left corners. You will see an accumulation of leaves. Look at the bottom tray and you will see leaves. Those things sit there forever, collect water and corrode metal. Get a light that will light things up in that area. I took 1/4" rod and bent it to get it to fit in that 2" left hand gap corner while laying on my stomach and trying to work around the radiator fan blades. Pull some leaves out of the spaces, get the 3' crevice cleaner for the shop vac and suck up the leaves. Repeat as needed. Then spray with whatever cleaner you want and then hose the radiator from inside a couple times.  Start the engine and immediately go to the rear for the bubble machine. You will get a perfect view of the fan's air flow through the radiator by the bubbles. It's never the total radiator, just what is behind the fan. No Pressure Washers allowed.

Gary 05 AMB DST

[vanwill52]

MTR Fleet Services in Cumming, GA was excellent for me to deal with when my ECM crapped out.  Jason, the owner, is a most pleasant, honest young man who explains everything without BS.  I would use them again any time!

And I should also give thanks to Paul Whittle, who put me up for three weeks while the process of getting a replacement ECM drug on.

[bestins]

Thanks for reply on how you clean it. I assume a garden pump up sprayer would be good for spraying cleaning soap into front of radiator(while you're laying on your belly upside down).

[Tom Cherry]

31 minutes ago, bestins said:

Thanks for reply on how you clean it. I assume a garden pump up sprayer would be good for spraying cleaning soap into front of radiator(while you're laying on your belly upside down).

YES.  Don't go crazy and use a power washer to rinse it off.  THAT is DISASTEROUS....but has been done and cost a fortune.  Even a garden hose without a nozzle will work and you use our hand over the end.  My pump puts out 60 PSI....I will not use a high flow nozzle for fear of bending the fins.

As to washing...There was an OLD recipe that I used and posted and it varies from memory.  There are commercial degreasers that folks have used....some used home version heated steam (low pressure obviously) as well for the engine.  I SHUDDER...and don't do that...

My old formula was a 5:1 Simple Green (water to concentrate) mix.  YES....Simple Green IS SAFE....look it up...an INTERNET myth.  but they DO sell a specialty product....but I have used this for 14 years...  Add maybe a quarter cup Black Magic Bleech White.  That is a POTENT substance....no more.  I mix up a ONE GALLON mixture....so that is on 2 OZ in 128 or a 60:1 ratio... (Water to Bleech White).  A copious SHOT of Dawn or any other really good grease cutting dishwashing soap.  The soap acts as surfactant to keep the solution ON the surface and react or dissolve the grease.

I spray it about any way I can.  BUT, on the front side (I have a Side Draft), I spray horizontally FIRST....then go back and do a Vertical...  That is how I always apply any penetrating sealant to masonry or concrete walks or drives.

THEN RINSE.  Your call on running or trying to expel all the soap.  I make a little dam with the hose and catch the run off.  Then I lift and let it go.  Then I rinse again.  when there is no suds in my little dam....it is rinsed...

[bestins]

Thanks for the explanation and info. Wishing now I had known enough to purchase a machine with the side radiator.

[DavidL]

And I use a power washer to ensure that the fins are clean on both sides since you can really only access it from the outside.

Yes, it can cause damage to the thin fins if you are spraying on an angle, using too tight a nozzle, too close, and using too high a pressure setting.

But, when you know how to use the tool, it's invaluable.  A hammer can cause a lot of damage if it's not used with skill too.  I powerwash a LOT (living in the woods, on a lake, with toys...) and it is a HUGE time saver.

Edited July 19, 2023 by DavidL

[bklaes]

4 hours ago, bestins said:

How are you getting to the radiator to clean from the inside, or what tools are you using.  Like you I've always cleaned mine from the rear, looking at the front of radiator from the access hole in the bedroom, I don't see a way to really give it a good washing. 

On my bath and a half floorplan, there is an access panel in the floor of the rear closet.  I get good coverage using the wand on the 1 gallon sprayer, and spray nozzle on the end of the hose.

[Gary 05 AMB DST]

Has anyone individually cleaned out the bottom corners and track as I described? Look at Scotty's photos. Where is the most damage? If you don't remove the crud, it will just pile up. You're not removing anything, just packing it tighter.

Gary 05 AMB DST

 

 

 

 

 

 

[Bill R]

2 hours ago, Gary 05 AMB DST said:

Has anyone individually cleaned out the bottom corners and track as I described? Look at Scotty's photos. Where is the most damage? If you don't remove the crud, it will just pile up. You're not removing anything, just packing it tighter.

I have.  Here are a before and after picture.  I affixed a light duct metal to seal the gaps so leaves don't get in as easy.  Pretty much the same method on belly, very tedious, bent clothes hanger to pull out, lots of water spraying, and totally soaked when done.  Stays clean now.

 

[6Wheels]

MTR comes with high accolades.  Being a Cumming resident, I can attest to their reputation!

[Scotty Hutto]

On 7/19/2023 at 7:44 AM, Steve P said:

…When you know the total cost of this project, please add that to the post for the benefit of those of us who are cringing. 

So I got the coach back yesterday, and all is well! (Except my wallet, which apparently went on a significant diet…)

All numbers include parts, labor, etc.

CAC Removal, Cleaning, and Repair
Estimate - $1,200
Actual - $1,075 

Radiator Removal & Replacement (includes new radiator, all new hoses, clamps, and coolant)
Estimate - $4,000
Actual - $4,033

Not included in original estimate, but added at my request during project:

Replace water pump & belt - $754 (shaft had significant play, minor leak)
Install stainless steel surge tank (labor only) plus new hoses, fittings, and clamps, and reattach snorkel (air intake) piping - $350
Dash A/C - Evacuate, test, replace leaking quick-connect with crimp-on fitting, vacuum test again, charge and test system) - $385

Please note that most of these items were very labor intensive, and the cost of repairing the same items on your coach - even at the same shop - would likely be different.

Typical engine temps on the drive home… low of 177°F once warmed up, peak of 190°F during a long hill climb on I-575.

Dash air blows cold for the first time in ???   🥶 The leak was a fitting that was apparently added when my compressor burned up about 3 years ago. (Different shop) I’ve been chasing that leak ever since…

I am extremely pleased with MTR Fleet Services, the quality of the work, their prices charged, and the speed of their service.  The only delay came when they called me on Friday to say they were putting off finishing my coach until Monday because they had a regular customer who had an emergency repair on his revenue generating vehicle.  I had told them I needed it by this Friday 7/28, so it still fit my time frame and I still got it early.

Will definitely be using them for future service, even though it’s about a 1-1/4 hr drive.

[96 EVO]

I thought Chris discontinued his stainless surge tanks?

[jacwjames]

Glad you got it all worked out,

Overall prices seem in line with others except for the water pump, which I assume they did while cooling stack was out.  Was the price a Type-o, I checked the price for a replacement on my ISC and its' ~$150, and would take ~1/2 hour to change at most.  

 

[Scotty Hutto]

46 minutes ago, 96 EVO said:

I thought Chris discontinued his stainless surge tanks?

He did. I bought one two years ago and just now put it in… 😞 

43 minutes ago, jacwjames said:

Glad you got it all worked out,

Overall prices seem in line with others except for the water pump, which I assume they did while cooling stack was out.  Was the price a Type-o, I checked the price for a replacement on my ISC and its' ~$150, and would take ~1/2 hour to change at most.  

 

There was other work associated that I didn’t detail out. 

[Robertpk]

I had to replace my radiator 2 years ago after a trip to Florida. After I removed the radiator and took it to the repair shop the fellow told me it was the second one he has done so far that year. He told me they were bad for rotting g out In the corners. Cost was$1300 for a custom made unit.

[GringoScot]

After "starting production of the bubble factory" I still encountered some areas where my high intensity LED light was not fully visible from the rear of the radiator.

Upon closer inspection I found that the heat shield material, that lines the interior of the engine doghouse (under the coach rear floor), was fraying and had become lodged in the lower corners of the radiator.  After a good vacuum to clear the debris, my water temps have dropped about 10 degrees from previous levels. 

[dl_racing427]

On 7/28/2023 at 8:44 AM, Robertpk said:

I had to replace my radiator 2 years ago after a trip to Florida. After I removed the radiator and took it to the repair shop the fellow told me it was the second one he has done so far that year. He told me they were bad for rotting g out In the corners. Cost was$1300 for a custom made unit.

Robert,

Who made your custom radiator?
I'm afraid this will be on my list of things to eventually replace.  $1,300 doesn't sound that bad to me.