Community Forums

vettenuts · 07-03-2020, 06:50 AM

I have a 2015 Tiffin Phaeton with the rear radiator. The manual states to clean the CAC from the fan side. I pulled the floor up yesterday to change the coolant surge tank and noticed that the cooling fan is huge and would make cleaning from the forward side difficult at best.

Do you guys clean through the inside floor access or is there another way to do this? I did buy an angled fitting for my pressure washer, but know better than use this at high pressure due to cooling fin damage that can result. Thinking about making a setup that attaches to my garden hose and uses the fitting rather than using the pressure washer itself.

Looking for lessons learned as I got the feeling I am going to take a bath (literally) doing this task.

R.Wold · 07-03-2020, 07:43 AM

also interested in replies....

**Lt Dan** · 07-03-2020, 10:02 AM

You definitely don't want to use the pressure washer and your idea about a garden hose attachment is your best bet. Most will soak liberally with Simple Green or similar cleaner then do a combination of cleaning from the inside hatch and reverse washing from the rear.

BTW, just noticed your signature still shows the 2005 Newmar.

vettenuts · 07-03-2020, 01:48 PM

Quote:

Originally Posted by Lt Dan

You definitely don't want to use the pressure washer and your idea about a garden hose attachment is your best bet. Most will soak liberally with Simple Green or similar cleaner then do a combination of cleaning from the inside hatch and reverse washing from the rear.

BTW, just noticed your signature still shows the 2005 Newmar.

Whoops, have to change that.

Cat320 · 07-03-2020, 04:40 PM

Would it be possible to post a picture?

vettenuts · 07-03-2020, 09:31 PM

Quote:

Originally Posted by Cat320

Would it be possible to post a picture?

Picture of the CAC?

Piros1 · 07-04-2020, 01:30 AM

I haven’t cleaned mine but we have on my company trucks. The only way to really clean them was to remove them. What we found was dirt and grime would build up between radiator and the CAC, no matter how hard you tried thee was no way clean between them. I you do it on a regular bases it may need to be pulled until
You start having cooling issues.

vettenuts · 07-04-2020, 05:22 AM

Quote:

Originally Posted by Piros1

I haven’t cleaned mine but we have on my company trucks. The only way to really clean them was to remove them. What we found was dirt and grime would build up between radiator and the CAC, no matter how hard you tried thee was no way clean between them. I you do it on a regular bases it may need to be pulled until
You start having cooling issues.

The Freightliner maintenance schedule actually calls for it to be checked/cleaned every six months, which would certainly keep any major buildup of dirt in check. I highly doubt anyone does this, but if a simpler method can be developed for cleaning I would certainly try to be more proactive in cleaning both the CAC and the radiator. I don’t think the normal RV owner runs it enough for six month cleaning, unless of course you spend a lot of time in dusty areas like the BLM sites out west.

I did scope out the view from the rear bath, and a garden hose can be passed up from below past the muffler so some cleaning can be done from inside the coach. I think a ball valve in the hose fitting to turn the water on and off will be immensely useful and using one of the inflatable type hoses will help maneuver it through the tight quarters from below. The manual does state to use a non-corrosive cleaner like Simple Green prior to flushing.

Xmcdog · 07-04-2020, 05:32 AM

Avoid any ammonia based cleaners. Not good for aluminium parts.
This is going to be a wet and messy job. Hey, sounds like fun. Get the grand kids involved!

OCM · 07-04-2020, 09:32 PM

I just replaced the expansion tank on my 2000 Damon Ultrasport, and have had the cooling problems that are rampant on rear radiator/CAC Diesels. While under the coach, with nothing else to do, I noticed a brace/radiator support under the radiator that is bolted between fame members. It looks like you could remove the support, and gain access to the space between the CAC and radiator without pulling the radiator. I cleaned mine by spraying some kerosene from the rear (while it was warm, not hot) let it soak for an hour , then washed it out using a Harbor Freight pressure washer, which will not come close to the pressure of my gas engine driven one. Then I sprayed Simple Green liberally from both sides, pressure washed, and repeated. Before I leave on the next road trip(in a couple of weeks) I'm going to repeat the whole thing. BTW the amount of kerosene is about a pint per event. I just took it out on a route that I normally have overheating problems, and the results were dramatic. When I get back I'll try the brace removal trick and see what happens. Stay tuned boys and girls.

Piros1 · 07-05-2020, 12:19 AM

Quote:

Originally Posted by vettenuts

The Freightliner maintenance schedule actually calls for it to be checked/cleaned every six months, which would certainly keep any major buildup of dirt in check. I highly doubt anyone does this, but if a simpler method can be developed for cleaning I would certainly try to be more proactive in cleaning both the CAC and the radiator. I don’t think the normal RV owner runs it enough for six month cleaning, unless of course you spend a lot of time in dusty areas like the BLM sites out west.

I did scope out the view from the rear bath, and a garden hose can be passed up from below past the muffler so some cleaning can be done from inside the coach. I think a ball valve in the hose fitting to turn the water on and off will be immensely useful and using one of the inflatable type hoses will help maneuver it through the tight quarters from below. The manual does state to use a non-corrosive cleaner like Simple Green prior to flushing.

I think a regular cleaning every six months or when you clean the Coach sure won’t hurt. I doubt the average RV owner would pull the CAC to CB lean it. That is a real process especially on side radiators like I have. My CC came out the bottom so unless you had a pit, loading dock or heavy equipment lift you probably wouldn’t be able to do it.

Two coaches back I had a rear radiator Journey and it came up and out the back. It was still a heavy unit to remove.

vsheetz · 07-05-2020, 12:36 AM

2011 phaeton here.

Annually I use a garden sprayer with Simple Green EXTREME. Spray and soak, front and rear, then let sit awhile. Flush with clean water. Repeat. Start the engine and watch the bubble show.

Access is pretty good reaching with the sprayer wand through the air cleaner access panel in the DS rear compartment.

vettenuts · 07-05-2020, 06:03 AM

Definitely won’t be a fun job on my back[emoji16]

bandcworkhorse · 07-05-2020, 09:43 PM

Just cleaned mine after 28.5k miles. 2015 Freightliner XCR, 400 hp ISL 9 chassis under a '16 Ventana 4002 body. I mention all this because after reading the forums long enough, it's clear there are a LOT of running assembly line changes, design, and parts supplier changes, etc. that come into play over the years. There is a lot of talk about accessing the space between the CAC and radiator. On mine, crossmembers and supports cover all sides of the assembly. In the one spot I can see both radiators obliquely, there doesn't appear to be any space between them. Parts Pro shows the CAC bolted to the face of the radiator. According to a guy at FL, the two are indeed sandwiched very close together and believed that cleaning between them would be nearly impossible. Once again, your results may vary.

Anyway, as others have done, I simply opened the vertical part of the engine cover in the rear bath. No reason to take the horizontal cover up, and it provides a flat surface to lie on while cleaning. I filled a bug sprayer with a mix of Simple Green for metal and water. Sprayed the CAC as best I could through and around the fan blades, then went outside to spray the radiator from the rear. Let it sit for a few minutes, then flushed with a water hose, both from inside (love that emergency exit door) and outside for several minutes. Started the engine, and watched the bubble show.

Just for fun I then sprayed the mix through the running fan. As others have said, virtually nothing blew back into the bathroom. Wish I had taken a picture of THAT mound of bubbles behind the rv! Followed with more flushing with the hose. Whole process took 2 hrs., incl flushing birds nests from under the bedroom slideout cover.

Bottom line: water collecting underneath wasn't particularly dirty. My engine compartment is covered in fine dust, and no doubt some of that collects on the radiators. So it's probably a good idea to flush out what you can.