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Topic: Aquahot tank leaking coolant into exhaust. Ouch! (Read 1192 times) previous topic - next topic

Aquahot tank leaking coolant into exhaust. Ouch!

Coolant reservoir slowly drops and antifreeze smelling steam in the exhaust on startup.
Unit was rebuilt by Aquahot in CO 6 years ago and I think the installer in MT mucked it up.
No fix without total replacement with a reman unit...$7g's plus...ergo the ouch.
Going to try $40 boiler leak stop.  Anyone else done it?  Will report my findings in a week or so.
If that fails, I found a matching used unit at one of the RV wrecking yards as an option, and can sell parts off this one. 
Love my aquahot as much as I love the coach.  Wish me luck.
2001 4010 U320 build #5865 "Bluto-d-Bus" since 09/18
2006 Honda Element ESP Toad
Full timing since 2016 in Western MT
Copilot: Sitka
1975 GMC 260 Avion: sold

Re: Aquahot tank leaking coolant into exhaust. Ouch!

Reply #1 –
Mine leaked thru the exhaust as well.  I discovered the leak came from the rad cap and was flowing over the top and side then on the exhaust. Have you checked that?
Peter    Alberta Canada
'98 U320 40'  Build 5359 M11 450 HP, Aqua hot, Blu Ox

Re: Aquahot tank leaking coolant into exhaust. Ouch!

Reply #2 –
I had the same issue with my Monaco, coolant in the exhaust. Used about 2 gallons a year. At the time John Carrillo wanted 10 cb's to repair it. I sold it and told the new owner it was his choice $40.00 a year or $10k now.
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: Aquahot tank leaking coolant into exhaust. Ouch!

Reply #3 –
That's my thoughts exactly Chuck.  If the leak stays the same, I can deal with it.  If it get's bigger, I'll punt.  If the leak stop voodoo gives me 5 more years....Hallelujah!!!! 
2001 4010 U320 build #5865 "Bluto-d-Bus" since 09/18
2006 Honda Element ESP Toad
Full timing since 2016 in Western MT
Copilot: Sitka
1975 GMC 260 Avion: sold

Re: Aquahot tank leaking coolant into exhaust. Ouch!

Reply #4 –
First thing I'd do is to change the radiator cap. While you're doing that look at the filler neck and see if that has any leaks. If so there is a fairly easy fix for that, search the forum. Or better yet call Rudy!
Forest & Cindy Olivier
1987 log cabin
2011 Roadtrek C210P
no longer 1999 36' U320 build #5522
2013 Rzr 570 & 2018 Ranger XP1000
2006 Lexus GX470
2011 Tahoe LT 4x4
Previous 1998 45' 2 slide Newell, 1993 39' Newell

Re: Aquahot tank leaking coolant into exhaust. Ouch!

Reply #5 –
How would coolant get INTO the combustion chamber and exhaust from a leaking radiator cap???
2001 4010 U320 build #5865 "Bluto-d-Bus" since 09/18
2006 Honda Element ESP Toad
Full timing since 2016 in Western MT
Copilot: Sitka
1975 GMC 260 Avion: sold

Re: Aquahot tank leaking coolant into exhaust. Ouch!

Reply #6 –
 Not sure. The only fluid leaking that I can discover is a leak from the rad cap which is running across the top and down the front side. I presume dripping on the exhaust down pipe. When I soak up the fluid and it is dry the drip on the exhaust stops.
Peter    Alberta Canada
'98 U320 40'  Build 5359 M11 450 HP, Aqua hot, Blu Ox

Re: Aquahot tank leaking coolant into exhaust. Ouch!

Reply #7 –
Found the confirmation evidence of a failed boiler tank today when rebuilding zone pumps.  Here's what the combustion chamber looks like with an internal tank leak according to Rudy....it will be obvious....this is mine 6 hours after draining the tank.  It would have been really wet if the tank was still full.  I'm waiting for the boiler seal to arrive and will let that do its thing for a week and report back.  Sure hope it works. 
2001 4010 U320 build #5865 "Bluto-d-Bus" since 09/18
2006 Honda Element ESP Toad
Full timing since 2016 in Western MT
Copilot: Sitka
1975 GMC 260 Avion: sold

Re: Aquahot tank leaking coolant into exhaust. Ouch!

Reply #8 –
All the best Woody.  Hope the stop leak helps
Rudy Legett
2003 U320 4010 ISM 450 hp
2001 U320 4220 ISM 450 hp
1995 U320 M11 400 hp
1990 Granvilla 300 hp 3208T
Aqua Hot Service Houston and Southeast Texas

Re: Aquahot tank leaking coolant into exhaust. Ouch!

Reply #9 –
I think it's safe to call this a Foretravel Christmas present/miracle..Aquahot's been running for a week with unlimited heat and no leaks, so the tank/burner chamber leak may be "fixed" for the foreseeable future.  Knock on wood.

Last week I drained the aquahot (coolant looked surprisingly clean and clear), rebuilt 3 of the leaky circulation pumps with new o-rings from PumpVendor.com, filled and primed pumps, topped off and flushed system with distilled water, then drained 9 gallons, added 8 gallons of antifreeze, a quart of Silver King boiler stop leak and topped off with distilled water.  Been running for a week with no more white steam in the exhaust and zero loss in the overflow tank.  Only disappointment is the coolant is now Bosco colored from the Silver King goop.  No idea yet if I need to keep the stop leak in there or if I can flush it out down the road.

Sorry, Rudy, but still might need to see you in a year or so???!

Here's some pictures of the pump o-ring leaks (defective install of original/rebuilt o-rings) and correct o-rings for these model pumps.
2001 4010 U320 build #5865 "Bluto-d-Bus" since 09/18
2006 Honda Element ESP Toad
Full timing since 2016 in Western MT
Copilot: Sitka
1975 GMC 260 Avion: sold

Re: Aquahot tank leaking coolant into exhaust. Ouch!

Reply #10 –
Well, there went all my money, I mean don't be sorry for me.  I congratulate you and the fix and do hope it is long lasting indeed.  Bravo for you!!!

And, bravo on the pump rebuild.  These older heaters will go a long way.  All the best.
Rudy Legett
2003 U320 4010 ISM 450 hp
2001 U320 4220 ISM 450 hp
1995 U320 M11 400 hp
1990 Granvilla 300 hp 3208T
Aqua Hot Service Houston and Southeast Texas

Re: Aquahot tank leaking coolant into exhaust. Ouch!

Reply #11 –
Woody
So do you think the leak stop fixed the issue with the white steam around the exhaust port under the coach?  I thought the rad cap would solve the issue I had but not so.  Now the rad cap has no leaks from it but I still get some antifreeze smelling white smoke from under the coach as well as in the ah area. Can you advise?
Peter    Alberta Canada
'98 U320 40'  Build 5359 M11 450 HP, Aqua hot, Blu Ox

Re: Aquahot tank leaking coolant into exhaust. Ouch!

Reply #12 –

The boiler leak stop worked for me.  I picked this product mainly for country of origin.  Amazon.com: Silver King SBSL 1 Quart SAFE LIQUID BOILER STOP LEAK With...  Zero leakage in over 2 weeks of constant use.

Followed the bottle directions and I thoroughly mixed the stop leak into a 5 gallons of distilled water before pumping into the tank.

It was a crap shoot, but I figured it was worth a try to spend the $40 vs. $7000.  Best bet of my life so far.

Sounds like your coolant leak is not into the combustion chamber proper, but still leaking from the tank to the atmosphere around the exhaust flange.

Best of luck.

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2001 4010 U320 build #5865 "Bluto-d-Bus" since 09/18
2006 Honda Element ESP Toad
Full timing since 2016 in Western MT
Copilot: Sitka
1975 GMC 260 Avion: sold

Re: Aquahot tank leaking coolant into exhaust. Ouch!

Reply #13 –
Without draining the tank can I just remove rad cap, siphon a bit out and add the bottle?  I really don't want to drain everything if possible
Peter    Alberta Canada
'98 U320 40'  Build 5359 M11 450 HP, Aqua hot, Blu Ox

Re: Aquahot tank leaking coolant into exhaust. Ouch!

Reply #14 –
You don't have to drain the tank.  But I would pull enough out, a couple gallons would do, to get a good mixture with the stop leak...it has the consistency of Hershey syrup. 

Quote from: Peter –
Without draining the tank can I just remove rad cap, siphon a bit out and add the bottle?  I really don't want to drain everything if possible
2001 4010 U320 build #5865 "Bluto-d-Bus" since 09/18
2006 Honda Element ESP Toad
Full timing since 2016 in Western MT
Copilot: Sitka
1975 GMC 260 Avion: sold

Re: Aquahot tank leaking coolant into exhaust. Ouch!

Reply #15 –
Woody
Would not the sealer clog the registers, requiring eventual replacement of them?
Peter    Alberta Canada
'98 U320 40'  Build 5359 M11 450 HP, Aqua hot, Blu Ox
 

Re: Aquahot tank leaking coolant into exhaust. Ouch!

Reply #16 –
No.  It's advertised for use in hydronic heating systems...the register pass throughs are very large and not exposed to the atmosphere.  My system is working great after 3 weeks.
2001 4010 U320 build #5865 "Bluto-d-Bus" since 09/18
2006 Honda Element ESP Toad
Full timing since 2016 in Western MT
Copilot: Sitka
1975 GMC 260 Avion: sold