Florida to Wyoming in my Class A

[Burker99]

Hi Everyone,

I just made a trip from Florida to Wyoming in my 2001 Monaco Knight with a Cummins ISB 5.9 with 300 HP and an Allison 3000 transmission. I also am towing my 2011 Tuscan on a tow dolly. The trip was about 2300 miles and the RV turned 100K on the trip. Traveling through FL. AL. MS. and MO. was pretty uneventful. I started across Nebraska from Omaha to North Platte and the rig ran fine.

After leaving North Platte west on I-80 toward Cheyenne the road started heading up hill. No big grades just a constant up hill run for like 200 miles and about 3000’ elevation gain. As the day went on and got hotter to over 90 degrees, I started running hot. Up around 200 degrees. I was getting nervous and pulled over to cool the rig down. I even called Cummins who said I would be fine as long as no warning bussers went off. That didn’t make me feel better.

I got to Cheyenne and was there for a coupe of days so I did some reading on this and other RV sites and learned that A LOT of people run at 200 or more. I still was hoping to get my temp down. My rig runs at about 185 on flat land. I even stopped and talked to a local diesel shop. Between my research and the diesel mechanic it sounded like clogged radiator fins. When I got back to my RV I crawled around under it found there was oil build up on the radiator. So after about 2 hours of hosing it down I got it pretty clean. I don’t think the 5 star resort I was at will ever notice the oil on the dirt patch they called a sight. 😊

While waiting for DW to get a hair cut I noticed an RV just like mine in the Walmart parking lot. I knocked on the door and the owner was very nice and invited me in. I asked about his rig and how it preformed. He had a 315 HP motor. He said both are RVs are under powered. I think I have to agree.

The owner said he was leaving Cheyenne at night to make the grade near Laramie without overheating. He was pulling a Tahoe. I was not happy to hear this but I was not leaving at night.

I left Cheyenne about 9:00 A.M. for Rock springs the grade over to Laramie was no problem. But the other thing I learned and did was to keep my RPM at about 2200 and shift down when needed to keep them there. The rest of the day was fine. One looong grade before Rock springs the rig did get close to 200 but cooled down at the top.

My last day from Rock springs to Star Valley went fine except for a 2-3 mile 8% grade before Afton. The rig actually did OK. The temp did get up to about 200 and I was in 3rd gear before cresting the top.

I am now in Star Valley for a month before heading back to Florida. All down hill (haha) This was the first big trip with this RV. If my return trip is no more eventful than this one I will be happy.

So, a couple of things I’ve learned are, make sure the radiator is clean keep the RPM up to 22-2300 on long grades and use the shifter to keep them up and not wait for the trans to hunt for the gears and loose power in doing so.

I am interested in any advice you all may have or anything I can do to improve the ride on the way home.

Thanks, as always

[mackwrench]

I just made same trip, North Florida to Montana.....
Some of the same roads as you. Before I left Florida I removed the charge air cooler and washed out radiator. (Side radiator)
While my dash temp gauge would occassionly go past 200, I had my scan tool plugged in and ECM temp never got over 195

[completelymo]

I just ran mine up to Central Oregon(Bend) from Hood Canal, Washington via Mt.Hood than back over Mt.Hood through Portland and back to Hood Canal. It was mid 80's on average with some places like Warm Springs, Oregon 96* where I encountered a very steep and long run up to Mt.Hood. My coach is 1997 American Eagle with a 325hp Cummins and side radiator. I had 150 gallons of fuel on board, 1/4 fresh water tank, empty holding tanks, fully stocked and loaded coach and a my temp range was between 180-220 depending on grade, length and outside air temperature towing a Tahoe.

I think the 2200-2300 rpm is good advise as I found my Allison waiting to long to shift down so I started to do it manually like you described and found I wouldn't lose momentum.


Hope this helps,

Mike

[doc]

In an emergency situation several years ago with a Detroit engine in a 2000 Itasca Horizon, Freightliner chassis, I backed up to the quarter car wash and spent a few bucks spraying degreaser, prewash, soap and hot water. It was amazing the debris that was washed out. Next trip to Freightliner chassis in SC, they steam cleaned the radiator and got rid of the oil residue and road grime. They installed a vent pipe to allow the crankcase breather to vent below the bottom of the radiator. no more problems.

The cause of the trouble was the breather was venting into the radiator and cooler cause the fins to clog. Govt regs a few years later and the outside vented crankcase breathers are a thing of the past

[jacwjames]

We bought our rig in late 2008 and through the good fortune of being laid off work in early 2009 we made a ~15K trip to Alaska. Never had a problem with over heating. We weren't towing anything and we do have a side radiator.

The only time I remember having a problem was in Albuquerque NM back in 2015 while driving up a long grade, I didn't make sure the rig downshifted so the RPM's were not up and the rig started to get hot. Got a warning from my Silverleaf VMSpc (gotta love it) and downshifted and the rig cooled right back down.

Keeping the RPM's up on long grades is a must.

[Gary RVRoamer]

Both Cummins and Freightliner assure me the engine is fine up to around 206 and able to handle short periods even higher. I've seen 212 on a downhill, but never more than 206 climbing a grade. In fact, the ECM manages the fan speed and doesn't even go to max cooling until somewhere around 200. I'm able to monitor both the ECM engine temperature and the transmission temperature as well as the dash gauge

[BigEvi]

I'm confused as I often am. Is it bad for the temp of coolant in a DP to be over 200? How does the liquid/vapor water get boiled out of the oil if its run so cool?

My car runs 240degf. But it is new and the new cars are designed that way for efficiency.

My airplanes...I have to cover the oil coolers in the winter to get the oil temp up to 200 so liquid and vapor water byproduct of combustion boils out.

I have a 5.9 Cummins in my pickup truck and it runs 190-200 all the time when warm and working normally.

Have a Cat C7 330 in my Fleetwood. The needle sits just left of center but there are no temps on the guage...I was assuming center was the 200 deg range I had become accustomed to in other vehicles.

I thought many of the Tstats were designed to open around 200-210 and close at 190ish? Maybe moho engines are different? I have always thought 200 was perfectly fine. I think properly mixed coolant with a proper pressure cap wont boil over until up in the 250-270 range...which would be pretty bad for oil to get to...generally the oil temp tracks coolant temp.

-E

[steveschlott]

Originally Posted by mackwrench

I just made same trip, North Florida to Montana.....
Some of the same roads as you. Before I left Florida I removed the charge air cooler and washed out radiator. (Side radiator)
While my dash temp gauge would occassionly go past 200, I had my scan tool plugged in and ECM temp never got over 195

Mackwrench,
I was on I-70 climbing to the Eisenhower Tunnel last weekend and about 100 yds from the entrance my overheat light came on. Since I was at the top I keep going and it cooled down and the light went off after about a minute. I think I need to clean out my radiator as well and I was wondering if there is any tricks taking the charge cooler off? I assume you did that to gain better cleaning access.

[mackwrench]

Ha-ha, no tricks...I did try and do it without disconnecting the hyd hoses to the coolers, no issues getting the CAC out, but ended up removing the oil lines to reassemble. The hyd cooler fins are to flimsy and I ended up having to straighten a bunch out.lol.....I lost about 2 gallon of hydraulic oil.

Not a bad job, about a hour and 1/2 to r&r the CAC, another hour or so to wash them both. So about 3 hours total.

Once CAC was off, I sprayed a fair amount of simple green on CAC and radiator. I took a gallon Ziploc bag and large zip tie & covered the now exposed CAC hoses to keep water spray out. I used garden hose spray nozzle pointed directly onto fins about a foot or so away.

It took a few applications of simple green, but I wouldn't quit into all I got was clear water running out backside of radiator.

I boondock often in a large grassey field under a big oak tree, lots of grass clippings!

But if you were to crawl under it, there wasn't any "apparent" restriction.

If you ain't washed it out, I'd highly recommend it.
Peace!

[KiteSquid]

I was told by Spartan to use the aluminum safe version of simple green. I think they Market it as aircraft cleaner.

It will be very safe for your very expensive radiator and charge air cooler.

[steveschlott]

Originally Posted by mackwrench

Ha-ha, no tricks...I did try and do it without disconnecting the hyd hoses to the coolers, no issues getting the CAC out, but ended up removing the oil lines to reassemble. The hyd cooler fins are to flimsy and I ended up having to straighten a bunch out.lol.....I lost about 2 gallon of hydraulic oil.

Not a bad job, about a hour and 1/2 to r&r the CAC, another hour or so to wash them both. So about 3 hours total.

Once CAC was off, I sprayed a fair amount of simple green on CAC and radiator. I took a gallon Ziploc bag and large zip tie & covered the now exposed CAC hoses to keep water spray out. I used garden hose spray nozzle pointed directly onto fins about a foot or so away.

It took a few applications of simple green, but I wouldn't quit into all I got was clear water running out backside of radiator.

I boondock often in a large grassey field under a big oak tree, lots of grass clippings!

But if you were to crawl under it, there wasn't any "apparent" restriction.

If you ain't washed it out, I'd highly recommend it.
Peace!Attachment 256373Attachment 256374Attachment 256375

Mackwrench,
I have two cooling assemblies mounted on the outside. Are those CACs? Based on the Spartan manual I have, there are three cooling assemblies sandwiched together; CAC, transmission cooler, radiator, going inside out. It does not show the two assemblies mounted on the outside.

[mackwrench]

The 2 coolers with lines are Hydraulic oil coolers. The CAC is what you see behind them.

I tried to leave the lines on and lay them aside to remove the CAC, but ended up taking lines off.


The transmission cooler is not in there. It's under radiator, a round heat exchanger that's plumbed into the lower radiator hose.

[153stars]

Your CAC is inter cooler for turbo it's going to have very large air pipes going to it. Those look tied together from pic and I would think be hydralic/power steering cooler Somewhere you have a condensor for your dash AC.as well.

[steveschlott]

I'm not comfortable removing anything since I am only a shade tree mechanic! I started by soaking everything with Simple Green Heavy Duty (it supposed to be metal friendly) then used a household steam cleaner that seemed to work pretty well. I flushed everything with water really well. It looks better and I set a bright light inside by the fan and spot checked for blockage it looked pretty clear. The real test comes next week when we head out from Colorado to Mich, Ohio, and Illinois.