I would like to clean my rear radiator more often but I have been told (by two different repair shops) that I need heated water or steam and at least 2000 psi. You spray straight on so the fins do not bend. I was told I needed that to get through the radiator clear to the back. I looked and I cannot find a way to access the back of the radiator. I have a Cat C7 350 hp. The problem is the power washers that heat the water cost a LOT of money - over $2K. However, it gets expensive to take it in to be cleaned. Are there any other choices?

In our area we can rent hot water pressure cleaners. Look for a Hotsey dealer in your area and ask them who rents one. Most shops prefer to use hot pressure cleaners because it's faster - they don't have to wait for a cleaning solution to work on the dirt and they don't have to do it several times. Also cheaper for the customer that way. However, other than beer, your time is free.How often do you clean the radiator and you do have a slobber tube installed? I have a C7, 350 that I've only cleaned once. It stays cool on the steepest hill I could find in western Canada, Teton Pass and up to the Eisenhower Tunnel.HotseyBill

2000 psi seams high can bend a lot of radiator fins causing more problems then dirty radiator.

I have been having the radiator cleaned once per year and it was pretty dirty each time it was cleaned. Unfortunately, there are no Hotsey dealers near me.

ncrowley, Let's put it this way. First of all, has your radiator EVER been cleaned and or, the "CAC" or, Charge Air Cooler, that sits in front of it? The blow-by tube or, "Slobber tube" as it's also known as, can make a mess out of both of them. That oily mist does coat both of them and then, your fan acts like a giant vacuum cleaner and sucks up all the dust particles it can and deposits them onto the CAC and Radiator fins. And yes, a couple more things here. One, if your blow-by tube has not been extended either by a CAT service center or, by a person such as yourself, it needs to be done so that the oil-mist has way less of a chance to get deposited on there again, especially after a good cleaning. Two, yes, on many of the DP units that use CAT engines, it's incredibly difficult to gain access for a good, quality, thorough cleaning. Some, have actually cut an access hole in the top part of the shroud as large as they can, and make the part they cut out, a door. Then, they use some sort of sprayer and spay as much of the CAC and the Radiator as they can with the correct Simple Green or, 409 or, whatever chemical they choose, into as many of the fins as they have access to. Then, they use a garden hose with a nozzle or tip to assist in blowing anything that's loosened, out the front side of both. Our coach is an '04 Itasca Horizon 36GD with the C-7 330HP CAT and, long story short, it had a radiator leak. I watched it for quite a while 'cause I knew it was going to be a serious chore to remove, repair and replace it. But, in getting ready for a trip one time, I did a good inspection inside the bed area. What I found was amazing. Over 40% of both the CAC and the Radiator were incredibly clogged up due to that slobber tube. So, I pulled them both. Now, here's the deal. I used some ZEP, citrus based industrial degreaser on that radiator, while it was laying on some saw horses. I also have a 2650 psi pressure washer. I'd apply a full, wet coat of that cleaner on those fins and, it wouldn't even drip through them. I then started using a pressure washer at quite a distance, all the while keeping a close eye on the fins to see if there was any damage happening. As I got closer and closer, there still appeared to be no damage to any of the fins. I finally put three coats of that ZEP on it and, each time would pressure wash it. After the third application, I started to see it blow through the other side of the fins. And, that was a serious ton of black goo. There was no way on this planet that I could have done that while those two components were still in the coach. Other guys say they've had good luck cleaning them in the coach but, I knew doing it that way, would have never worked 'cause I would have not gotten as close to the fins of both the CAC and the radiator as I did when they were out.So, my point, the fins on those radiators are quite strong. Does that mean you shouldn't take precautions while attempting to use a pressure washer, NO. It simply means that I did it, and, it worked, and I did absolutely no damage to those fins, from approximately two inches away from the fins. And, that includes doing the CAC, which is ALUMINUM, in the same manor. Pulling that radiator and CAC was a chore, to say the least but, it not only allowed for really good cleaning of them but, it also allowed for up close and thorough inspection, maintenance and repair of any of the forward bearings of that CAT. That was the serpentine belt tensioner and idler pulleys. And, the water pump tensioner and idler pulleys. I did not do the fan bearing 'cause I could not break the Allen head bolts loose. Next time. Scott

I have asked two Cat dealers about extending the slobber tube and they both had never done it and did not recommend it. Yes, I have read the threads about doing that but I want to be sure it is done correctly. Yes, I know that the way the slobber tube is now, it is blowing gung onto the radiator which is why I would like to do this more than once per year. This last trip, we went up and down a very steep mountain and blew gunk all over the toad and the back of the coach so I am sure the radiator got hit as well.Talking to the mechanics, it takes a lot to get through the radiator and the CAC to clean off the gunk. They have steam cleaners at high pressure to do the job.

Power Wahser to Clean Rear Radiator | Good Sam Community

rgatijnet1
Explorer III
Aug 05, 2014
All radiator fins are NOT created equal. If you have an older coach, where the fins could have already corroded to the fragile state, then even a moderate amount of water pressure can damage them. If you have a newer coach, then careful use of a pressure washer may be fine. Just use the spray head with a WIDE pattern that spreads the pressure over a larger area. The best thing is to inspect your radiator first to try to determine the condition of the fins. If you have spent a lot of time in the salt belt there is a good chance that your aluminum fins may be on their last legs.
FIRE_UP
Explorer
Aug 05, 2014
SNOPRO711X wrote:
I have just been reading this thread because my 2003 Itasca with 3126 Cat 330 hp engine was overheating last week. I removed the engine cover in the bedroom and took a good look at the CAC from the inside. It did not appear to be very dirty to me but I will clean it with Simple Green Extreme as soon as find some.

I think I will try a pressure washer, I have been cleaning condensers on airconditioners for years with a pressure washer. If you are carefull the fins will not get damaged.

The slobber tube on my MH comes down to just below the bottom of the CAC and then extends slightly to the rear. There is no evidence that the slobber tube has gotten anything on the CAC, it has slobbered on the trailer hitch mount. There is no need to extend this slobber tube?

"If you are carefull the fins will not get damaged."

Imagine that, someone who's making sense. Thinking outside the box, in terms of how things are done or repaired or serviced on motor homes, is sometimes, the name of the game. Not all "fins" are created equal. A buddy of mine, in preparation for a long trip to the Winnebago/Itasca Grand National Rally in Forest City Iowa, decided to wash his basement A/C fins out with a garden hose and a nozzle, in an effort to clean all the dirt off the fins so it would work more efficiently. Before he knew it, he'd bent about 75% of the fins over, completely flat. And this was with a garden hose.

But, as I stated in first post about this, I used a pressure washer on my radiator fins, starting out from quite a distance and slowly moving inward, to the point that I was about, 3" away from them and still, checking VERY FREQUENTLY if I was damaging any of them.

NOT ONE FIN, was ever bent, using my 2650 psi pressure washer at about 3" away. Now, if one is not happy about the thought of using a pressure washer, then DON'T! It's as simple as that. No one's forcing anyone to. Those of us that have done it, and with good results, know what works and what doesn't. I know that in my CAC and Radiator, a garden hose, and 10 zillion gallons of water, was NEVER going to work. I used industrial ZEP degreaser and it still took a pressure washer to knock all that stuff loose.

So, anyway, choose your poison. Whatever makes you happy and, the method at which you use to get it clean, is entirely up to you. Good luck.
Scott
FIRE_UP
Explorer
Aug 05, 2014
SNOPRO711X wrote:
I have just been reading this thread because my 2003 Itasca with 3126 Cat 330 hp engine was overheating last week. I removed the engine cover in the bedroom and took a good look at the CAC from the inside. It did not appear to be very dirty to me but I will clean it with Simple Green Extreme as soon as find some.

I think I will try a pressure washer, I have been cleaning condensers on airconditioners for years with a pressure washer. If you are carefull the fins will not get damaged.

The slobber tube on my MH comes down to just below the bottom of the CAC and then extends slightly to the rear. There is no evidence that the slobber tube has gotten anything on the CAC, it has slobbered on the trailer hitch mount. There is no need to extend this slobber tube?

"If you are carefull the fins will not get damaged."

Imagine that, someone who's making sense. Thinking outside the box, in terms of how things are done or repaired or serviced on motor homes, is sometimes, the name of the game. Not all "fins" are created equal. A buddy of mine, in preparation for a long trip to the Winnebago/Itasca Grand National Rally in Forest City Iowa, decided to wash his basement A/C fins out with a garden hose and a nozzle, in an effort to clean all the dirt off the fins so it would work more efficiently. Before he knew it, he'd bent about 75% of the fins over, completely flat. And this was with a garden hose.

But, as I stated in first post about this, I used a pressure washer on my radiator fins, starting out from quite a distance and slowly moving inward, to the point that I was about, 3" away from them and still, checking VERY FREQUENTLY if I was damaging any of them.

NOT ONE FIN, was ever bent, using my 2650 psi pressure washer at about 3" away. Now, if one is not happy about the thought of using a pressure washer, then DON'T! It's as simple as that. No one's forcing anyone to. Those of us that have done it, and with good results, know what works and what doesn't. I know that in my CAC and Radiator, a garden hose, and 10 zillion gallons of water, was NEVER going to work. I used industrial ZEP degreaser and it still took a pressure washer to knock all that stuff loose.

So, anyway, choose your poison. Whatever makes you happy and, the method at which you use to get it clean, is entirely up to you. Good luck.
Scott
SNOPRO711X
Explorer
Aug 05, 2014
I have just been reading this thread because my 2003 Itasca with 3126 Cat 330 hp engine was overheating last week. I removed the engine cover in the bedroom and took a good look at the CAC from the inside. It did not appear to be very dirty to me but I will clean it with Simple Green Extreme as soon as find some.

I think I will try a pressure washer, I have been cleaning condensers on airconditioners for years with a pressure washer. If you are carefull the fins will not get damaged.

The slobber tube on my MH comes down to just below the bottom of the CAC and then extends slightly to the rear. There is no evidence that the slobber tube has gotten anything on the CAC, it has slobbered on the trailer hitch mount. There is no need to extend this slobber tube?
Trackrig
Explorer II
Jul 29, 2014
The Simple Green will clean heavy oily residue quicker. Dawn is formulated for dishes - SG is formulated for dirt. Yes, they use Dawn to cleaned oiled birds in oil spills, but that's because it's the safest cleaner they use on birds that also removes oil. A radiator isn't a bird and can take a better (harsher) cleaner. Dawn will probably work, but how long do you want to spend at it?

Bill
deandec
Explorer
Jul 29, 2014
What does Extreme Simple Green do that Dawn soap does not?
ncrowley
Explorer II
Jul 29, 2014
I have purchased the Extreme Simple Green and will be using that. Thanks.
RayChez
Explorer
Jul 29, 2014
I think you might be making a mistake by using so much pressure with a Hotsy washer. We used them on the railroad, but everything there was heavy duty.

What I done was purchase an electric power washer. They just spray water at higher speeds then a regular water hose nozzle. I lift the bed and go in through the bed box to get to the engine. I spray the CAC and radiator real good with Simple Green with the spray washer. Let it set for about ten minutes. I then spray with clean water with the electric spray washer. I also start the engine so that the fan will push the water through the fins. Caterpillar engines push the air out instead of sucking the air in. So it works pretty good for me and my CAC and radiator are kept clean. I do this once a year.
I also go to the rear and spray the outer side real good. But the most important is that CAC because it is sandwiched to the radiator and grim does get in there.
Canadian_Rainbi
Explorer
Jul 29, 2014
wolfe10 wrote:
BobGed wrote:
Do not use regular Simple Green as it leaves a residue. Use Extreme Simple Green

The other reason to use Simple Green Extreme is that it is Aluminum-friendly. And most CAC (Charge Air Coolers) are aluminum.

Remember, the VAST majority of the dirt is on the front of the CAC, which "filters" the dirt before it gets to the radiator which is behind the CAC on the vast majority of rear radiator coaches.

X2 or 3 on the Extreme Simple Green. We have used it with success, washed off with a garden hose. Never thought of spinning the fan as someone mentioned earlier. I wonder why I didn't. :h :S

Rig was in the shop last week and they said it didn't need cleaning! :)
ncrowley
Explorer II
Jul 28, 2014
Thanks! I will be putting this on and then cleaning the radiator.

I am going to have the dip stick calibrated the next time I have an oil change. It is sitting at the Fill mark right now. I will leave it there and watch it carefully.