Community Forums

wolfe10 · 09-15-2020, 07:35 PM

Quote:

Originally Posted by Nalle

So, steam cleaning seems like a waste of time and money. If your engine starts overheating, have the radiator and CAC pulled and get it done right. $2000 later, you should be good for another 5-6 years.
I have had no oil leaks or other contributing factors. This is just road dirt picked up by the rear tires and very efficiently blown thru the radiator and CAC by the fan.
To me, it is a pretty lousy design. Maybe a side radiator is better??

If the steam cleaning is ONLY from the back-- I agree, a waste of $$, as the vast majority of the debris will be on the FRONT of the CAC and to a lesser degree, the front of the radiator. No way to really do a good job from the back/outside. It has to be accessed from the front (bedroom or closet depending on floorplan).

Cougarkid · 09-15-2020, 07:39 PM

The CAC is sandwiched together with the radiator. If you don’t know it is there, you would just think the radiator is really thick !

The issue on the rear radiator setup is that junk/gunk/dirt gets sucked up in between the two and gets stuck. The buildup restricts AIRFLOW through the radiator, causing higher running temperatures.

It seems the only way to really get them clean is removal. A bit of work, but worth it in the end.

BTW: if you run a lot of dirt or gravel roads, it will get dirty quicker. The air (dirt) get sucked up from UNDER the Rv and then pushed through the CAC/ radiator.

geordi · 09-15-2020, 09:30 PM

Quote:

Originally Posted by Cougarkid

The CAC is sandwiched together with the radiator. If you don’t know it is there, you would just think the radiator is really thick !

The issue on the rear radiator setup is that junk/gunk/dirt gets sucked up in between the two and gets stuck. The buildup restricts AIRFLOW through the radiator, causing higher running temperatures.

It seems the only way to really get them clean is removal. A bit of work, but worth it in the end.

BTW: if you run a lot of dirt or gravel roads, it will get dirty quicker. The air (dirt) get sucked up from UNDER the Rv and then pushed through the CAC/ radiator.

They are not always stacked one in front of the other - My 2002 Diplomat has the CAC above the radiator. I have not attempted removal of either, but pressure washed both sides of both of them and what I found on the engine side was not dissimilar to the pictures on the first page of this thread. They were both nasty. With a low power electric pressure washer and a LOT of degreaser sprayed through, I have seen a reduction in operating temperature of at least 25 degrees (in August yet!) and slightly better boost overall. Boost could still be better however, but that is likely other things.

nodine · 09-16-2020, 03:51 AM

Rear radiator coaches usually have the CAC stacked on top of the radiator and side radiator coaches have the radiator and CAC sandwiched together. On a rear radiator coach like we have you can pull the CAC and leave the radiator installed. That way you don't have to drain the coolant and there is a large opening above the radiator that you can work thru to clean the radiator, pull the fan, etc. Look at the photo below. This is with only the CAC and fan removed and the top of the radiator can be seen at the bottom of the photo. The CAC can be cleaned in the driveway before it is reinstalled.

Bob

Nalle · 09-16-2020, 05:26 AM

Quote:

Originally Posted by stevestancil

I have had overheating issues since I purchased my 2005 Diplomat. Everything has been done except replace the radiator. The radiator has not been pulled out and cleaned. What is the CAC?
I have been told now the next step is do a flow test on the system. Any suggestions.

Steve.
The Radiator and CAC are stacked together, with the CAC between engine and Radiator.
Looking from behind the RV my Radiator looked spotlessly clean. And, crawling under, you can not really see the condition of the CAC because of the fan shroud. Not until it was removed did we find the condition you see on my pictures. If you have an 05 with over 50,000 miles, it is probably time. I am close to 140,000 and is will soon be time to pull it out again.

stevestancil · 09-16-2020, 06:46 AM

Thanks Mike. Do you feel that would solve the problem?

rikadoo · 09-21-2020, 07:31 PM

Hey Stevestancil one other thing to look at before flow testing the radiator, most people DONT consider, rather than rely on the gauge, because lord knows I have seen many fail, is to get a code reader that can look at the information coming into the ECM (engine control module) because the type of sender for a temputure gauge is completely not as accurate as the ECT (ENGINE COOLANT SENSOR) that the engine looks at. I have a MAC tool scanner that can look at input from the engine sensors to determine if I have a faulty temp gauge sensor. Just more info to make your brain squirm... sorry

stevestancil · 09-22-2020, 10:36 AM

Thank you for that suggestion. We have done this. Also the computer read out verifies the temperature gauge. It is definitely running hot on hot days and pulling hills.

I appreciate your advice.

stevestancil · 09-22-2020, 10:38 AM

Good thinking. I will ask this question.

Terry L T · 10-07-2020, 05:54 PM

While you have it apart go ahead and replace the fan, my 9 blade fan now has only 1 blade left. It left me on the road over a thousand miles from home. The fan took out the radiator and the CAC. It is plastic and 17 years old with about 88,000 miles.

bpu699 · 10-07-2020, 06:40 PM

Quote:

Originally Posted by wolfe10

If the steam cleaning is ONLY from the back-- I agree, a waste of $$, as the vast majority of the debris will be on the FRONT of the CAC and to a lesser degree, the front of the radiator. No way to really do a good job from the back/outside. It has to be accessed from the front (bedroom or closet depending on floorplan).

This...

My new to me dp was over heating for the prior owner on hills. He had it steam cleaned multiple times.

When I took the bed engine cover off and looked it was completely clogged with mud, dirt, etc...

Sprayed with simple green extreme, and a regular 50psi garden hose. Did it several times. Put the garden hose right up to the fins and ran it until clean, from all sides.

Got a garden extension wand too, took the fan belt of so I could spin the fan...

Now, I can see light clear through. Put a bulb in the engine bay and look from the back for light. The difference was literally night and day...

No need to spend $2000...