heater hose to aqua hot rupture

[HHIDan]

Originally Posted by DBeauchamp

On my unit there were two hoses (1 in. OD) going from engine to Aqua Hot and two separate hoses (3/4 in. OD) going from engine to front cab. heater. There was a Y connector near the transmission for the return lines so you only see three connections near engine. Only my Aqua Hot line ruptured and it cost us $600 for towing and $800 for a splice (plus all of the inconvenience). Replaced all the 1 in. hose with my brother, took 2 days, lots of dirty work... Replaced the plastic Y connector with a galvanized steel connector and put two shut off valves near engine.
And yes the hose was like wet noodle....
And BTW, if you shut off these hoses you not only loose engine pre-heat but you loose the "free" engine heat while you're travelling which to us is of much greater importance. Note that the coolant is circulated by the engine when the engine is running. Engine Pre-heat is done by a separate pump at the Aqua Hot and not all systems are equipped with that pump. (Easy to retrofit).
And I later found out that this sub-quality hose was used for a while at Newmar 04 to late 06 and it affected a number of coaches, so could be the same in your case.

As per my earlier post the two return lines are connected thru a Y connector back to radiator. Did they see the Y connector or is it perhaps between the rails? If the Y is between the rails then it's the return from the cab heater that's leaking. Note that your cab heater/AC thermostat must be set to warm in order for water to circulate thru the cab heater otherwise the TempCon valve is closed. You also want to make sure you run the heater so the two lines fill up be4 you adjust the coolant level.
After I cut my hoses I blew air into each one to make sure which was which at the Aqua Hot and to ensure I was dealing with the right ones...

[EngineerMike]

Dan- on Alpines they used (at least 08 & later) two taps to the back of the engine block, so each of the cab heater & AHot return get their own barb fitting to the block. Likewise on the feed lines, each has its own tap, tho those are on the thermostat end of the circuit so they have pressure from the coolant pump. So our rigs have two entirely separate circuits, which according to info so far (outside of speculation by Cummins) are simple out & back circuits.

Sounds like Newmar took a (very logical) shortcut by doing the Y fitting for return.

[Orman]

Hi Guys
The heater hoses can and will fail on any coach, Coach manufacture or year does not mater
it all depends on the hose the coach manufacture uses at the time of manufacture.
Fast, Easy repair can be made by connecting the two ports out of the engine. Some owners coach do not install new hoses. As we all know Alpine never planned on having to replace them

[kraig]

One tip Roger Berke gave me when you replace the engine hoses to the Aqua Hot was to leave them 2-3 feet longer to the Aqua Hot and leave the slack on top of the Aqua Hot. If you have to remove the Aqua Hot you have some slack to work with. When I removed my Aqua Hot I also did the same for the rear Aqua Hot hoses that run to the front of the Motorhome. This makes it a little easier to get it out.

[HHIDan]

Originally Posted by Orman

Hi Guys
The heater hoses can and will fail on any coach, Coach manufacture or year does not mater
it all depends on the hose the coach manufacture uses at the time of manufacture.
Fast, Easy repair can be made by connecting the two ports out of the engine. Some owners coach do not install new hoses. As we all know Alpine never planned on having to replace them

I hear what you're saying but in '05 quite a few Newmars had hoses that failed. If you search a little you will hit a few threads on this forum.

[Cinequip]

Tom,

I noticed in your picture that the dash A/C hoses run right next to the Turbo, just like mine, which just failed due to heat. I suggest you take a look at the nearest hose to the engine for baking of the rubber, and then create some space. My high pressure line was situated about 3/4" from the 90 degree turbo outlet. See my post today for pictures.

[EngineerMike]

Mine run the same but WRV wrapped them in silicone/fiberglass heat wrap

[Alpine Road Warrior]

Thanks to all who replied. Mechanic read what was posted and got the fix done. We are back on the road again.

[Just Cruising]

We had the same problem in the middle of nowhere. Patched it to get home. We then had to pull the black tank (not to bad) to reach the back of the Aqua hot hoses. We installed bulk head fittings at the bulk head and ran reinforced hoses to the AH. We replaced all hoses in the engine compartment and this fixed it so we can replace hoses up to the bulk head and the ones behind the AH should last for many years. hope this info might help.

[Dave Fernandez]

For MY $0.02, sorry if someone already posted this suggestion.
Way back in the 70’s when CHP was using the big 440 Dodges they were suffering a 99% hose failure with the rubber hoses. Patrol cars usually run 24/7 through the shifts. They idle for hours at crime/accident scenes, day/night, winter, summer, deserts, and mountains.

When they changed to Silicone Radiator and heater hoses in the late 70’s they reduced the failure rate to about 5% with a fleet of about 1000 patrol vehicles. Now all Police Patrol vehicles come from the factory with silicone hoses today with very few failures. Silicone heater hose is not cheap, it can be found for under $4.00 per foot if you spend some time searching for it.

Silicone Heater Hose 5/8" X 50' Roll Per Foot, 80-062, Purosil Burke Rubber - Ryder Fleet Products

You should also use a shielded hose clamp on silicone hose.

Amazon.com: lined hose clamp: Industrial & Scientific

I plan on replacing the hoses on my Alpine with silicone since it should out live me.

[kraig]

After reading the threads about heater/aqua hot hoses, I thought I would see what I had my ISL 425 built in May 2007. Both my heater/ aqua hot hoses were OEM THERMOID brand heater hoses made for cars and light trucks with manufacture date May 2003, so it was 4 years old when built. It was their cheapest hose. The hoses are 10 years old now and were not a heavy duty hose for diesel engines. Although they did not fail, I replaced all of them with Goodyear Hi Miler Blue hose. All the information in both posts were the same as mine. I replaced all the hoses all the way to the heater and Aqua hot. I did add 4 shutoffs near the engine if I ever had a problem.

The reason I am posting this, there is 3rd pressure hose buried way under the a/c and alternator bracket, left of the heater feed hose. If you have to remove the alternator, the battery feed is hot even with the disconnects off. This 5th hose ran along side of the other heater hoses except there is 360 degree loop (maybe they had extra hose) above the parking brake and continues inside the frame through the rear bulkhead. I can't find a a 3rd return hose. I replaced this feed hose away from the engine and put in a 5th shutoff, but could not replace the rest of the hose. It doesn't tie into the other 4 hoses since I did test each of them by blowing air through them. After I put it all back together, no leaks, so it does not tie in somewhere.

Does anyone with 2008-09 have this extra hose. If open the rear engine, I can see both of them directly under alternator. Mine is an APEX, but I don't what would be additional.

[Just Cruising]

I checked on my 2008 (built in March 2007 I think) and it doesn't have the hose you are describing. I hope you can find where it goes to as Murphy's law says it will rupture where you can't see it. With that said I hope it never does.

[kraig]

Marvin- One question, do you have the 400 Cummins?

On the extra hose, I replaced it to down inside the frame and put in a shut off and connected to old hose. I may shut it off and see what happens. Once it goes into frame foam insulation on rear bulk head, cant see where it goes.

[Just Cruising]

Yes, I have the 400 Cummins