Experience With Radiator Replacement

[ncrowley]

I have a 2004 Newmar on a Freightliner chassis and a Cat C7 engine. I purchased it when it was 8 years old and had 12K miles on it. After I had it about a year, I found out about extending the slobber tube. Before that, I went to Speedco to have the oil changed and they overfilled it, resulting in covering the front of the toad with oil. Then I learned about the amount of oil needed and extending the slobber tube. We then extended the slobber tube..

We have been cleaning the CAC twice a year with Simple Green Extreme the way described on these sites, including running the engine to blow the solution as far in as we can. We have had the radiator steam cleaned from the back once per year at the truck repair place.

Over the last three years, I have had more and more problems with the engine temperature, even though I make sure my RPMs stay high and the speed stays low. I have made it where I needed to go but sometimes I get the warning light. It has never gone into limp mode. However, I did not like the behavior. I know there must be something wrong.

I have been working with a diesel shop and they said the radiator needed to go. They took it out today and I was floored by what I saw. Most of the back of the radiator was totally gunked up and one side of the CAC was too. There were grasses and junk all along the bottom.

I took a picture and you can see it here:

Radiator Pic

Here is the CAC:

CAC

At least I know why I was having temperature issues.

What I find discouraging is I spent many hours cleaning and it was just a waste of time. I do not know if it was clogging before I got it and it just continued, or if all that messing around with Simple Green does not do anything except make you feel better.

It is also discouraging that there is so much the manufacturers should have done and did not do. The slobber tube should have been extended from the factory. There should be something you can take off the bottom that will give you access to the space between the CAC and the radiator. There should be explicit instructions about how to keep this clean that actually works and a simple way to keep it clean.

The radiator is being replaced and the CAC is being cleaned. But how long will this last? I have no faith that the cleaning I will do will keep it from clogging again.

While it is open, they are replacing hoses, the water pump, the fan bearings, etc.

Sorry for this long post but I hope my experience will help someone else.

[gswcgi]

I have a CAT 3126E with a deep sump and CAT says it's a 30 quart engine. If you don't have a deep sump it may take less oil. My engine is not over filled at 30 quarts.

[FIRE_UP]

ncrowley wrote:
Fire Up - what I was wondering is how you got the camera in the space between the radiator and the CAC?

ncrowley,
It's been years since I did that job with that camera. I went from the top when the entire bed was torn apart and, that gave me about as much access as I was gonna get for fishing that camera lens around from a distance. I then got under the coach and fished it around from there. The CAC is shorter in height than the radiator so, I got some pics of some of the perimeter fins so, that's some of what you're seeing. But, the actual distance in between the CAC and the radiator is very narrow.
Scott

[rgatijnet1]

They have small boroscope cameras that you can hook up to your cell phone for less then $10.00, including shipping.
Boroscope

[ncrowley]

Fire Up - what I was wondering is how you got the camera in the space between the radiator and the CAC?

[FIRE_UP]

ncrowley wrote:
Fire Up - how did you inpect the radiator with a camera?

Here's one that a super quick search revealed. Mine is an old Costco unit but, they've got better ones now. That little camera's come in handy several times around the house and cars etc.
Scott

https://www.amazon.com/Vividia-Portable-Digital-Flexible-Inspection/dp/B00AIFSSUG/ref=sr_1_6/145-8413730-0657730?ie=UTF8&qid=1538585561&sr=8-6&keywords=inspection+camera

[Jim]

I've often wondered on my '02 Journey if I couldn't install some sort of hinge arrangement on the rad so it could be opened to both access the front of the engine and/or clean the rad?

Impossible? Possible?

Wonder if it's been done?

[wolfe10]

smlranger wrote:
Now that you have it clean and the slobber tube extended, you should be fine as long as you continue to do at least a good annual cleaning.

Yup, that is the secret. If done annually, it can still be cleaned with Simple Green EXTREME and a hose.

If allowed to completely clog, removal for cleaning/replacement is the only answer.

[smlranger]

Now that you have it clean and the slobber tube extended, you should be fine as long as you continue to do at least a good annual cleaning.

I owned a 2002 Journey and never liked the rear radiator configuration. It seems the manufacturers could reconfigure the rear radiator pusher rigs so that the radiator and CAC were stacked and not made in a sandwich. I suspect it has to do with the amount of surface they can expose to air.

[sailor_lou]

My rig was supplied with the CAC stacked on top of the radiator so there is no issue getting debris trapped between the components. If you are replacing items and plan on keeping the rig a long time maybe this is an option to consider. Good luck.

Lou
05 Travel Supreme Envoy
CAT C7 (with rear rad)

[tinkerer]

Last year I cleaned my rear radiator DP with the Simple Green. I didn't get a lot of dirt and grime running out but a fair amount. But when I finished I put a light on the engine side of the radiator and I could see through the entire radiator from the rear. I figured good enough. But since my coach is a 2007 the slobber tube is routed past the radiator. The only time the coolant temperature rises is on a long hard pull in 90 degree weather like the pull north Of Phoenix on I 17 towards Flagstaff. I usually just shift down and keep the RPMS at of above 2000 and it works. But one of these days I might be faced with removing my rear radiator to do the service you posted earlier.
Thanks for you information.:)

[ncrowley]

Fire Up - how did you inpect the radiator with a camera?

[ncrowley]

I had the dip stick recalibrated so it will not be overfilled again. I also give explicit written instructions about how much oil to use and what markings on the dip stick to use to the shop that does the oil change. Since that, I have had no issues with oil blowback.

A new radiator was ordered before the work was done. I decided to just replace it while it was pulled out because of the age.

No, I do not live down a dirt road and I rarely drive off payment. Somethimes the roads are gravelled. I really have no idea how all those grasses got in there. Maybe the people I bought it from got those in there.

I was thinking yesterday about folks that purchase coaches of my era that have no idea about these issues. I had no idea.

All of this being said, I really love my coach which is why I am willing to ut this money into it to keep it going a long time. Newmar did a good job with it and we plan to keep traveling in it for many years to come.

[FIRE_UP]

nccrowley,
What you found out is what I've been telling folks for years. And that is, attempting to clean the radiator and CAC on SOME of these coaches IS almost a waste of time, if they're left in the coach. You see, as you've found out, the conditions at which those two units live in, are tough. The dynamics of how things are lodged into the fins of both, are such that, attempting to clean them FROM THE SAME DIRECTION, plain just doesn't make sense. All you're doing is forcing the dirt/debris/leaves/animals/plastic bags/oil and more, farther into the fins.

I've pulled the radiator and CAC out of our coach, an '04 Itasca Horizon 36GD with the C-7 330HP CAT, twice now in 7 years. The first time was right after we purchased it, right at 6 years ago. I had a radiator leak and, upon inspection with an inspection camera, I found that the radiator was about 50% clogged and the CAC was almost the same. So, out came both of them. At that time, it took me about 6 hours 'cause I was not speed wrenching at the time. I'm retired and I could care less how long it took me.

Before I decided to toss that radiator, it took me an entire gallon of Zep, citrus based degreaser and three passes with a pressure washer to get it clean. You should have seen the road grime/tar/dirt/oil/bugs/leaves/ and anything else that came out of those fins. On our coach, there is absolutely ZERO possibility of cleaning either of those two units while in the coach.

Some folks have some luck cleaning theirs. On mine, IMPOSSIBLE. So, fast forward a few years and, recently I had to do some major maintenance on the front of that CAT C-7. A fan bearing, belts, new water pump, CAT's "Regulators" (us normal folk call them thermostats) all the hoses, and a few other odds and ends while I was in there. But, that radiator and CAC took me right at 3.5 hours this time. It helped that I was familiar with where all the fasteners were at and how hard it is to get to everything and developed short cuts.

Well, that was 40,000 miles since the first R&R and while my slobber tube has been extended all the way to the rear of the coach and, I always install the correct amount of oil anyways, I still had debris in mine. It's inevitable. I modified my radiator frame so it would allow for maximum amount of air flowing through it. Before I did that, the frame had gussets at each corner that were solid. Not good.

Anyway, as for Winne and Itasca and any other manufacturer not really allowing for easy access for easy cleaning of these items, well, this has been something to deal with for ever in these things. It is what it is.

Anyway, since my radiator, at 40K miles, (the first time I did the operation) was corroded so bad in a lower corner, it was non-repairable. So, out with the Aluminum-plastic and in with the Copper-brass. The cooling of the Copper-brass is pretty much the same as the original radiator. The changing of the regulators brought the temp down just a tad from 194 to 186 on the average, based on outside temps and level cruising or not.

Anyway, yes, it's real tough to try and to a thorough, efficient, accurate and complete job of cleaning while they're in the coach.
Scott

[Jim]

I was lucky that the original owner of my current Cat 3126e knew about these problems from the get go and had the dip stick remarked to 20 qts instead of going by the factory written (next to the fill tube on a metal plate) 22 qts. So when I bought this RV, and since I also knew about the issue, I paid close attention to the front of my car and to how much oil was used. Very little oily residue ever ends up on the front of my car. Now there are several who say that this model Cat uses 19 qts, but that's not always what the factory decides is correct. Which of course causes confusion.

I've tried to be observant and monitored the oil level so I'm pretty sure the 20 qts works fine for this particular setup. I've also been a conservative driver in the mountains like you and haven't had any overheating issues. I've also done the Purple Simple Green treatment, but just once. Sprayed the rad out from the back a few times too.

Now, on to the issues with your rads. They both look fine! Why replace that rad if there's no leak when a good soak and spray out will suffice? Just curious about that.

It also appears that you frequent an area where you're more apt to get a lot of dust and debris on your rad that the rest of us wouldn't. Do you live down a very long unpaved country road? Again, just curious.

Finally, it's not entirely clear...did you reduce the amount of oil used in the crankcase? Both my Fleetwood Cummins and Winnie Cat stop blowing oil at a reduced oil level. Might still need a slobber tube extension though.

Thanks for relating your experience. Knowing what others are doing about this issue is always helpful.