Diesel Pusher Coolant Lines

Ok, this is quite lengthy but I hope I can describe it well enough and hopefully it will be of benefit to anyone either wanting to tackle this job on their own OR take it to a shop to have the work performed and being familiar with exactly what the mechanic(s) will be faced with.

I tackled a not so pleasant job over the past week (what an understatement).  When I say week, YES I mean week.  I worked 8+ hours on Friday afternoon, my son and I finally called it quite about 8:30pm Friday evening.  Saturday we started promptly at 8:00am and closed up the shop @ 6:30 pm with ONLY stopping for about an hour for lunch.  I took a break and let my body heal on Sunday and we commenced again on Monday afternoon about 4:00 and finished up around 9:00 pm.  This was JUST replacing all of the radiator and coolant hoses, not pulling a vacuum and adding the 17-gallons of coolant which we did on Tuesday night.  A couple more odds and ends tied up and a road test is scheduled for tonight, Friday, one week later.  So if you were following along that is 23+ hours of hands down the worst job I have ever done and I have done some doozies.

Monaco at least ran some rigid lines/pipe along the upper chassis over the storage bays with hose nipples at the front for the dash heater core hoses/connections and at the rear over the transmission.  BUT they did not run rigid lines for the Aqua-Hot.  NOT only did they not provide rigid lines for the Aqua-Hot engine loop lines, BUT they zip-tied the heater hoses going from the Aqua-Hot to the engine in an area between the rear bulkhead and the Aqua-Hot bay, which measured about 34", to the rigid lines.  YES, you read that correctly, they zip tied the OEM rubber lines TO the rigid lines in a void or area that is 100% inaccessible once the coach was built.  I was completely dumbfounded.

It took me and my son over 4 hours alone just to get the lines separated and replaced from the Aqua-Hot unit to the rear bulkhead.  My arms were so cut up and I was bruised from trying to shove my body into a place that was too small.  On the rear, I could barely touch the one zip-tie, but couldn't get my diagonal cutters in there to cut that stinkin' thing.  At the rear, my son was able to trim about an inch more from the trim panel that at least allowed him to squeeze his arm in there and cut one zip-tie from his side.  The one in the middle we basically had to spray lube on and pull back and forth working the lube, then spray and repeat.  What a complete and utter pain in the ass.  This is nothing more than idiocy in full bloom.

Once we got that short section done, we were able to locate the rigid lines and replace one at a time from the back of the cylinder head of the engine to the hot side rigid going up forward, then the return side from the lower water pump area of the engine up to the rigid line. 

For the most part Monaco did a fair job of routing the lines to avoid chafing and/or rubbing of the lines and hoses.  The coach is 14 years old now and has 105k miles so nothing has failed on these lines yet so they must have done something right.  That being said, there was one area where the hose on the Aqua-Hot had rubbed on the housing of the cabinet chafing a small hole in the rubber hot side of the Aqua-Hot engine loop.  These hoses were routed in a tight area and making quite a sharp bend going up from the Aqua-Hot and then turning 90-degrees and heading towards the rear of the coach.  The hoses are almost non-visible until the wiring/wire loom is moved away from the Aqua-Hot.

Follow along and I will describe the pictures.

If you want a few more pictures and description I have a full thread of the repairs and mods to our 2003 Monaco Dynasty over on irv2.com.  Sorry I didn't post it here but this forum is a bit more troublesome to post pictures to or I would probably have the exact same thread here.  Here is a link if you are interested, this is starting with the coolant lines but there is a LOT more information on our coach throughout the rest of the thread.
http://www.irv2.com/forums/f115/mods-upgrades-to-our-2003-dynasty-237276-27.html

Now on to the pictures.  I will continue with other posts following:

First picture is with my 26 gallon drain bucket in place and starting the drain process.

Second picture is of all of the radiator soft and rigid lines removed, both upper and lower.

Third picture is of the upper radiator rigid tube beadblasted and ready for paint.

Fourth picture is of the upper radiator rigid tube painted with POR-15.

More to come......

First picture is of the lower radiator tube painted with POR-15 after sanding and prepping.

Second picture is where the Aqua-Hot lines ran up and over the cabinet.  This was not visible until the Aqua-Hot wiring was moved out of the way.  The red line(hot) was the one that was chafed on the underside. 

Third picture is of the engine loop HOT coolant hose that was chafed and ready to fail.  This did NOT have many more miles before a failure and dumping all of the coolant on the side of the road.  NOT a pleasant thought.

Fourth picture you can see the two rigid lines rearward of the rear bulkhead along with the two new silicone hoses for the Aqua-Hot.

Stay tuned.....

First picture is of "some" of the old hoses that were removed from just the rear of the coach.  This was my pile, my son was throwing his away as he was removing them.  Worth mentioning here, our first thought as we started this job was that we would merely attach the new hoses to the old and pull them through, YA RIGHT.  That did NOT work anywhere near as planned.  All in all there was nearly 100' of 5/8" heater hose on our coach with tie-wraps (or zip-ties if you choose to call them) about every 6-10 inches along the way.  I also opted to replace these coolant lines with silicone hose vs. the standard rubber hose.  I am sure I could have merely replaced them with the same material and probably not have any issues for another 14+ years but I have had good luck with silicone hoses in all of our coaches, plus I was able to have the cost whittled down a bit from my local NAPA.

Second picture is of the old Cummins thermostat.  I replaced the thermostat back in 2009 when I switched over to ELC coolant but I decided to replace it again.  Just FYI, the Cummins part number has superceded to a new part number so here is the new part #.

Third picture is of the new radiator hoses along with the old.  I have cut them to match here and they are ready for installation.

Fourth picture is showing the new lower radiator hose (45-degree) along with the two new silicone coolant hoses (blue hoses shown in picture) and the new 1.25" hose from the bottom of the surge tank to the lower radiator tube.

Don't go away, there's more............

First picture is of the new spray foam inserted where we had to cut the foam away and trim the panel a little to get the hoses from the Aqua-Hot out to the rear of the rear bulkhead.

Second picture shows how I routed the new silicone hoses for the Aqua-Hot.  I ran them to the rear of the Aqua-Hot cabinet similar to how Monaco ran them, but once I got to the top of the cabinet I routed them in a larger radius and up higher in the chassis so the hoses wouldn't rub or repeat the chafing on the Aqua-Hot cabinet.

Third picture shows the lines up high going over the Aqua-Hot cabinet.

Fourth picture shows the new silicone coolant hoses running from the front loom up over the generator, through the flow control valve and terminating at the dash heater core.

Last post to come......

While my son and I were under the coach on Saturday replacing coolant lines every once in a while we could hear a slight hissing sound.  I was continually moving lines around trying to locate where my leak was from.  My son finally located it.  The main air pressure line coming off of the engine compressor and terminating at the air dryer had rubbed a hole in itself.  The line was looped back over itself and clamped to some drop down brackets but there was two areas where the hose could rub against itself and was not secured.

I removed the line, took it to my local Evco on Monday and had a new line made up.  The picture below shows the old line.

All in all that is one job I am glad is DONE!!!!

Thanks for following along and I hope this is able to help someone looking to either perform this work themselves, or take it to a shop.  If you take it to a shop, please tip your mechanic and be greatful. 

I have had several people on another forum ask if I would be willing to perform these repairs on their coach and I will politely reply with a HELL NO!!!  If I wasn't so anal about wanting it done correctly and my lack of trust of anyone touching my coach, I wouldn't have done my own in the first place.

I am glad I replaced them as in addition to the one chafing, I found another one that was rubbing on a bracket and in more than several locations I could feel the hose crumbling internally as I was removing them.  There were not long for this world. :'(

Mike.

Mike,

That's a job I don't ever want to do!

I've looked at how the varies hoses and cables are run in the the Camelot and it's the same as yours and our 2000 Windsor. My Aquahot is worse only because its located in the first compartment up front (just behind the fuel tank). I had one small leak in one of the hoses to the engine coolant about 3 feet behind the Aquahot. It was from abrasion. All I did was patch it and then clamp over the patch. No further leaks in 3 years. I did pull all the panels and inspect for other potential abrasions. I use bicycle inner tube rubber and zip ties to make a wrap to protect from abrasion. I've probably done 20 of them.

I have had to have 4 slide hydraulic lines replaced (4 of 8). Lippert apparently used poor quality hoses and fittings. On the first one Monaco removed the old hose, but for the last 3 they left the old hose in place because removing them doubles the time to do the replacement! (Note all were paid for by extended warranty - along with a new hydraulic pump. Total bill for Lippert slide repairs is over $4,000.)

I just made a note for next winter, when were back in Arizona, to pull all the panels and inspect again.

I assume the area that was in accessible was over the holding tanks. I ran a second pair of 4/0 cables from the battery compartment to the Inverter. Getting cables over this area was not easy. They are not tied up, but just laying on top of the tanks.

Aren't motorhomes fun?

ken
 

Ken, sounds like you are VERY familiar with what is involved then. 

Something I hope I never have to do again, but I am sure I will, probably not this coach, but more than likely the next.

Mike.

At 16 yrs and 100K I'm in the planning stage of a belt kit and doing all the coolant hoses myself and so glad my gasoline rig be somewhat less $$$ Some will be a pita to get to as well.

William52 said:

At 16 yrs and 100K I'm in the planning stage of a belt kit and doing all the coolant hoses myself and so glad my gasoline rig be somewhat less $$$ Some will be a pita to get to as well.

Click to expand...

My first coach was a gasser and it was a piece of cake compared to this one.  Even my last coach wasn't too awfully bad, Beaver on a Gillig chassis and they too ran the lines above the storage bays in rigid lines, but the Aqua-Hot lines on this one were the worst I have ever done, PERIOD!

Mike.