Hi Folks:

Just learned, embarrasing as it was, that my 02 Winnebago Journey 36DL has a CAT C7 330HP engine. I thought that it was a Cummins because the dealer paperwork said Cummins 330. I crawled under the coach and observed a YELLOW engine, not RED. The label on the oil pan said CATERPILLAR. Now, here is my question:
I have developed an overheating condition when operating at normal highway/interstate speeds and climbing slight - long inclines. DOwnshifting into 5th or 4th on the Allison brings the temp into mid-Normal range at 2000rpm. I checked the interior face of the radiator/CAC and noted caked on dirt. Many folks have warned about pressure washing the rad. Any suggestions about cleaning tips? THANKS

Ohhhh, been their done that. I had the same problem. I used simple green, and a engine degreaser. I poured the simplegreen in a good spray bottle, kept it on a fine jet type spray and went throughout the radiator. I also crawled from the inside and did it from there as well. I let it sit for about a half hour then hosed it out with s pray nozzel, being careful the spray was not to powerefull to bend the fins. I did this numerous times, and I was amazed what canme out!

I also mixed some dawn dish detergent and water together and went through a couple cycles of that as well.

Others have stated that they use a garden sprayer which I have done as well. Some will start the engine then crawl under a spray again to get it sucked in.

I hope this helps.

Once you have your radiator cleaned, you really just need to learn to drive the coach. It is quite different than a car or even a large truck, atleast with my setup, I have plenty of power, but the engine will overheat easily if I don't slow down and keep the rpms up on even pretty minor grades if they are of any length. You really need to keep an eye on your temp gauge.

the BEST thing I did to learn to drive the coach and to aide in doing so was to buy and use VMSpc , it is a computer program/adapter box that plugs into your engine computer and allows you to load additional engine gauges, and more accurate one also. It responds fast than the dash gauges, and it also will tell you what gear the trans is IN not just selected. With some practice, you will also see how to drive for highest MPG.

John

Once you get the cleaning chore completed, to reduce the likelyhood of repeating this issue:

1) find your engine's crankcase vent or "slobber tube" and redirect/extend it, so the mist of oil that exhausts out of it isn't sucked directly up into your rad/CAC surface.
2) confirm that you and/or your mechanic are only putting 19 qts of oil in your engine. dont rely on the dip stick reading until its recalibrated for 19 qts. many of these dip sticks were set up for 22 qts oil, then Cat changed their requirment to 19 qts, to reduce all the excess oil being blown out the slobber tube and causing the problem you discovered.

do a Search on this or any RV forum for "Cat slobber tube", and you'll find this a very commonly covered subject.

Jim

I think you really need to get to the inside from the hatch under the bed to do the job properly. I took both the engine hatch covers off, covered the carpet around the bed with drop cloths. Pulled a garden hose thru the bedroom window (didn't let the wife see this, for sure ).

I bought my rig used and I was not sure this had been done before so I used a can of engine de-greaser. Let it sit then washed it with the garden hose. I followed with a good soaking with Simple Green from a garden sprayer...sprayed from the inside and from the outside. 15 minutes later, I washed it again with the garden hose, inside out, outside in.

The engine compartment and radiator looked like new.

Spooky, you are getting consistent advice:

1) Clean the radiator as others have posted on how to accomplish

2) Verify that your slobber tube is extended below the radiator level.

3) Good advice on verifying that your dipstick is calibrated to 19 quarts of oil. Call CAT with your engine s/n and they will tell you if it needs calibrated and how to do it. Overfilling the oil is a major reason for blow-by. If you have your slobber tube extended, it won't go into your radiator, just all over your toad.

How do you spray the radiator from the inside? I've cleaned it several times from the outside, but when I try it from under the bed looking over or around the engine all I can see are fan blades.
Wagonmaster2
2004 Meridian 36G

quote:

Originally posted by wagonmaster2:
How do you spray the radiator from the inside? I've cleaned it several times from the outside, but when I try it from under the bed looking over or around the engine all I can see are fan blades.
Wagonmaster2
2004 Meridian 36G

I actually crawled inside and sprayed around the fan blades. Turned the engine and then hit the other spots. It is not easy or fun, especially since I am not really small!

Oh, I also extended my slobber tube back, I have not had problems since doing this, but will constantly wash out radiator when I was the rig! I should have said this as well...thanks guys!

quote:

Originally posted by wagonmaster2:
How do you spray the radiator from the inside? I've cleaned it several times from the outside, but when I try it from under the bed looking over or around the engine all I can see are fan blades.
Wagonmaster2
2004 Meridian 36G

When I used the garden sprayer filled with Simple Green, I was able to work around the fans fairly well with the rather long sprayer nozzle. It's not perfect but seemed to get most of the radiator assembly. No doubt the fan blades get in the way some.

Posters who wash out their radiator keep talking about how much crud comes down from between the two radiators, but ever time I wash it from the back nothing but clear soapy water runs down. Makes me wonder whether there's nothing to wash out or if I'm not doing a good job.
Instead of extending the slobber tube and having it blown out on the rear end or toad, I fastened a pint plastic peanut butter jar on the bottom of the tube with steel wool in the bottom of the jar to help absorb the oil mist. I drilled several 1/4" holes around the upper edge of the jar for venting, and also empty what little accumulates in the jar 3 or 4 times a year. This has been working fine for me for the last 2 years. Has anyone developed any problelms from getting soap on the fan belt? Several years ago I washed my car engine off with a soap solution and the fan belt squeaked from then on till I finally installed a new one.
Wagonmaster2
2004 Meridian 36G

wagonmaster2, with your slobber tube oil collection system, I'm betting your radiator isn't getting too dirty! Hey, it works as designed!

Congratulations on a good solution.

How do you say THANKS for all the GREAT advice? This forum is really helpful. We've initiated the program of maintaining the cooling system better. The caked dirt (mud) accumulated on the interior of the CAC/RAD easily washed off and the degreaser cleaned the fan blades. The slobber tube was already extended below and to the rear of the fan shroud. The shroud interior was fairly free of grease/oil accumulation. I did not remove the interior engine cover (under the bed), but feel that the CAC/RAD is as clean as possible without removal of the CAC/RAD by dealer ($$$). THANKS again for all your help.

I had the same problem a couple of weeks ago in Southern Arizona. I stopped at a Freightliner dealer in Willcox and the mechanic spent about an hour spraying degreaser and power washing through the back of the radiator. He got a real wad of greasy residue off the radiator. I also had him put an elbow on the slobber tube to try to redirect the oil. He recommended that I do that once per year. He also, to my dismay, told me he thought my radiator had less than a year to live. Offered to put in a new one for $1800. I'm going to get a second opinion when I get home.

cyko,

I am curious why your mechanic thought your radiator only had a year to live. Thanks.

dreamer.

cyko - Put a plastic empty peanut butter jar on the end of the slobber tub to catch the oily mist and overflow before it blows out anywhere, in the radiator, on the rear of your coach, or all over your toad. Just empty the jar couple times a year. It just needs a few 1/4" holes around the top of the jar for breathing. Have been using this arrangement for couple years with no oil spray out anywhere.
Wagonmaster2