Pusher Radiator Cleaning

[JohnJill]

Well I got great advise on my first post so here I am again. Our coach has a over heating problem, the freightliner dealer has told me its a dirty radiator on the motor side. Is this something that I can do or is it best to have the shop take care of it.

[wolfe10]

Actually with a Freightliner chassis, you have SANDWICHED cooling system. The CAC (Charge Air Cooler) is in front of the radiator and is where the vast majority of the dirt and debris is deposited.

Yes, you can clean it yourself. Access the top of the motor/fan shroud area-- from bedroom or closet. Use a garden hose/nozzle. If just dirt, that is all you will need. If there is any oil or grease holding the dirt, you will need a cleaner. Dawn, Simple Green Extreme (Aluminum friendly), etc will work.

Be sure to wear old clothes, it is a pain to clean around the fan blades, but the fan blades sling the dirt to the perimeter where it is hard to remove-- particularly the lower perimeter.

Flush until the effluent is clear.

This needs to be done once a year.

Brett

[JohnJill]

Thanks again for the advise the dealer said there was quite a bit of blow back and grim on the inside and not much air movement coming out. We have just bought this coach and have not got my maintenance schedule down yet. But I have something new for my list.

[markstella]

What I have found to be helpful is to get a garden sprayer, got mine from Wal-Mart. Its about a gallon container with a small hose and a spray wand.
This helped to get in between the fan blades.Fill it with your cleaning solution and concentrate on that area infront of the fan. You'll be amazed at the crude that comes off. Be careful with high water pressure as that may damage your radiator fins.

[casuall454]

In the shop we use "Simple Green" to degrease and clean engines, transmissions and the such. There are numerous other cleaning degreasing agents on the market, just be sure to properly rinse away all cleaning products as some are corrosive in nature. If your concerned about the greasy run off from cleaning your radiator and engine block( watch run off to storm drains that may discharge to waterways ) you can look at the possibility of using a car wash as they have proper oil traps to separate hydrocarbons from water, also watch the use of high pressure water as you can damage your radiator cooling coils and any of the other external hoses, wires and the such.

Lastly; Consider buying a disposable painting tyvex suit and eye protection for use. That way your greasy clothes won't go into your washer.

[JohnJill]

Thanks again everyone,

Markstella I did get smart and thought of your idea before I read your posting and yes its the only way to do it. I used the Purple Degreaser and it worked OK but will try the Simple Green when I do round two Casuall454.

We took it to Beavers Creek over the weekend and evidently I am radiator clean cuz the temp never went over 190 LOL.

[Walt2137]

John,

I will pass two procedures the first one is what I used when we had a 99 Diplomat, the second I have not used but it looks pretty good but be sure to flush both real good with fresh water.

FIRST: I tried a new way to clean my radiator awhile back and it really got a lot of black gunk out. First let me say that I have cleaned the radiator 3 to 4 times a year for the past 4 years.

I used a 2 gallon garden sprayer the type with the wand and fill with 1 gal of Simple Green, on the 99 dip I can raise the bed to get to the radiator, I first sprayed with water ( be careful not to wet down the alternator) then soaked it real good with Simple Green, about a quart.

Closed the engine cover, cranked the engine, opened the engine cover and sprayed about another 2 qts of soap in the fan be careful with the wand-- don't get it in the fan, I dont think this would need to be done every time), closed the engine hatch and run the engine up to about 1500 a couple times to get the soap thru the CAC & radiator.

I then shut the engine down and let it soak for 30 minutes. Washed the radiator with water restarted the engine and washed with water some more, close the hatch run the engine up to about 1500, I did this a couple times. Shut the engine down and washed from the rear.

I was surprised at the black gunk that was between the CAC and Radiator. After testing I found that this method dropped my Trans temp by about 10 deg in city driving and in hilly country on those +90 deg days according to the VMSpc program that I run on my laptop.

I did not use a pressure washer (but I think you could with the gentle nozzle), I used the regular water pressure 50# with my hose and spray nozzle.


SECOND: Tom C cleaning procedure (this soap mixture may give a little better results )

2 Quarts of Simple Green. If you want to use a gallon of Simple Green, then that would be OK, but I would probably not put in more than three (3) quarts.

8 - 16 Ounces (1/2 - 1 pint) of Wesley's Bleech White Tire cleaner (Auto Zone or Walmart)

3 - 4 Ounces of Dawn (Blue) Dishwashing detergent.

Rest is water.

Wet down the radiator and knock off all the dirt. UNLESS you are well versed in using a pressure washer, DON'T. The fins on the CAC are VERY sensitive. Ordinarily a good garden hose sprayer nozzle and city water pressure will work.

Spray the radiator and CAC from EVERY angle that you can get to. You need to do it TWICE. The first time move the nozzle from left to right (or east to west). THEN go back over it and move the nozzle up and down (or north to south).

Let this sit for about 5 minutes. The Simple Green will remove most of the dirt. However, the Wesley's is as close to Caustic Soda as you can get and will really dissolve the grease and the grime. The Dawn acts like a surfactant to keep the solution on the radiator and lets the chemicals work.

NOW, rinse that sucker. Use every trick that you have been told and use the same logic for the rinsing. Rinse it from east to west and then from north to south. It NEVER hurts to rinse it again. The water will run off.

This will effectively clean most radiators and CAC's. If you have road tar or other gunk on it, then it might take STEAM, but that is best left to a
PRO. By PRO, I mean a diesel shop that understands HOW to use Steam and how to clean radiators without destroying them.

[wolfe10]

Particularly if you have an aluminum CAC or radiator, a STRONG caution against strong chemicals/non-aluminum friendly chemicals.

Simple Green does make an aluminum-friendly cleaner used for aluminum aircraft: http://www.simplegreen.com/solutions_faqs.php?search_query=aluminum

[billbaldwin]

I use Web Coil Clearner, works great.

Spray, let it set a few min, flush and spay again until flush water is clear.

bill

[ckcarpenter42]

This is a great discussion thread and evidences the rich support available on this forum.

An additional resource can be found on this specific subject for diesel pushers as all three major topics, (radiator and Charge Air Cooler location, cleaning technique and cleaning detergents) can be found on Cooling System board of the technical discussion forum operated by FMCA's Diesel RV Club: http://forum.dieselrvclub.org/index.php/board,4.0.html

[glidercoach]

We made some progress cleaning our DP CAC and radiator with Simple Green and water, but I wasn't convinced I'd gotten it all.

Found a truck shop with a STEAM cleaner (NOT a pressure washer), who did a great job getting much more out of the cooling fins. They did the work from outside (no need to go under the floor from inside). The steam wand was run in front, between, and behind the two units. Lots of black 'stuff' came out, and the coach ran cooler afterwards. This shop was in the high desert, and works on a lot of commercial vehicles that operate off paved surfaces. They told me they have some customer units that need to be steam cleaned every two months.

If your CAC and radiator have not been cleaned in some time (or you purchased a used unit), you may want to consider the steam method. Once totally clean, the regular owner-cleaning should be much more effective. Just remember: Steam (not pressure washer)!

[desertdeals69]

I use a product made by Spray Nine. Its called Grez Off. I spray it from the outside using a spray bottle and let it soak for about 15 minutes. Since its water soluble it rinses off easy. This product is capable of loosening the hardest baked on grease.

[wolfe10]

Just a reminder, the vast majority of dirt, oil and grease is on the front of the CAC. That, far more than the back of the radiator is what needs to be cleaned.

If cleaning from the back were able to clean the front of the CAC, it would send all that "gunk" onto the engine's front, alternator, water pump, belts, etc. Not sure that would be a very good idea.

[desertdeals69]

After I clean the radiator I spray the engine and wash it off. All of the parts are basically water proof or resistant or we couldn't drive in the rain.

[wildebill308]

JohnJill,

You didn’t tell us what year your RV is. One thing you can do on older units is make a catch bottle for the “slober tube” This is the crank case blow by vent on the side of your engine.

Most are to short and the oily vapors will get sucked into the CAC and radiator causing dust and dirt to stick and accumulate faster.

Some have just extended the tube. I use a catch bottle because it will get on the toad otherwise.

Bill

[wolfe10]

No problem with a "catch bottle" as long as (really important) it does not restrict air flow. As an example many diesels have a 1" ID crankcase breather hose. If you have any kind of "filter media" such as course bronze wool the bottle it will need to be several times the size of the breather. Said another way, a 16 oz plastic drink container is too small.

Also, if you are getting much oil from the breather, first suspect is that the crankcase is overfilled with oil. Diesel engines "puke" excess oil until their "natural oil level" is reached, then flow virtually stops.

And as Bill mentioned, another very good option is to extend the breather hose to behind the fan shroud so oil vapor will not be sucked in by the fan and blown into the CAC and radiator. Many chassis makers did this when the chassis was built and/or have retrofit kits to do it.

[wildebill308]

I used plastic mayonnaise jar. I cut a hole in the top big enough for the hose to go through the cap then put a clamp on the hose so it couldn’t slide off. I drilled a bunch of #30 holes in the upper part of the jar so it could vent with out restriction. I have seen the bottle attached with wire through the vent holes. So far it has drastically reduced the oily coating on the back of the coach, the toad and I am sure the CAC and radiator.

Bill

[Walt2137]

Bill if you are getting oil on your toad and the rear of the coach as Brett has said you are over filling your engine, The engine book will generally give you the oil needed to fill a dry engine not a wet engine. It is always better to be a little low on oil than over filling a engine be it Diesel, Gas or lawn mower. I had a 5.9 in a 99 Diplomat and I never had a problem with oil on the coach or toad but I did have to extend the breather tube to the rear of the CAC and radiator to solve the oil smoke coating the CAC etc.