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Topic: Antifreeze solution leaking from under water heater (Read 448 times) previous topic - next topic

Antifreeze solution leaking from under water heater

I recently took my 1999 U 2-70 in for radiator repair. We had just made it back home after a two week getaway on 9/15/20 when I discovered that my radiator had a small leak. I took it in to a radiator shop and had it repaired at a cost of $2,000. Picked it up today and drove it for an hour just to make sure all was ok. Drove it home and parked it on driveway no more leaks on radiator but now I have a leak of antifreeze from right underneath the water heater. It leaked into the compartment located directly under the water heater. At first it would appear that the water heater was leaking but it's antifreeze so what is going on. I have no clue. Why would antifreeze be leaking from this area.

Re: Antifreeze solution leaking from under water heater

Reply #1 –
There is an engine heat loop for the dash that runs through the water heater.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Antifreeze solution leaking from under water heater

Reply #2 –
Like Chuck says (above) you probably have the MotorAid heat option on your water heater.

Look for two black rubber heater hoses running up to the backside of your water heater.  One of the hoses may have a valve in it.  The hoses are connected to short nipples on the back side of the water heater tank.  There will be a hose clamp on each hose.  They are usually very hard to see and reach with your hand.  Clamps may be loose causing the leak.  Try to tighten them up and see if it stops the seepage.

After fighting these leaky hoses for several years, I finally cured the problem by adding a second hose clamp to each hose.
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: Antifreeze solution leaking from under water heater

Reply #3 –
So how exactly does this motorAid heat option work. I do have a blue gate valve that has wording that reads "Close for max dash heat". A black hose is connected to the valve and does connect behind water heater. So does antifreeze run throug the line? I used I mirror to see behind water heater and I can see three connections. Two are black hoses and the other not sure.

Re: Antifreeze solution leaking from under water heater

Reply #4 –
Engine coolant runs through those lines. When you close the valve, all the flow goes to the dash.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Antifreeze solution leaking from under water heater

Reply #5 –
Quote from: amata57 –
...I can see three connections. Two are black hoses and the other not sure.
Your coolant leak is probably coming from one of the black hoses.  The black hoses carry antifreeze.  The other plastic pipe is the cold water line supplying the water heater tank.

As you drive the hot coolant from the engine circulates around the water heater tank on its way to the front of the coach.  The coolant does not mix with the fresh water in the tank.  When you arrive at your destination your water is hot and ready to use even before you turn on the water heater (either propane or electric depending on the model of water heater).
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: Antifreeze solution leaking from under water heater

Reply #6 –
 Doesn't look much fun. I'm having it done next Spring
1996 U295-36, Cummins 300hp, 8.3. Build number 4864. Vin number 1F97D536XTNO54271. Purchased October 31, 2019.