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Topic: Small Coolant Leak at Water Heater (Read 970 times) previous topic - next topic

Small Coolant Leak at Water Heater

I opened the water pump bay this weekend to find these pictures.  Has any one else had this issue?  It's a pretty slow leak as it had been sitting for about three weeks.  I looked for about 5 minutes, but could not find where the leak was originating.  I'm wondering if its at the bend in hose, but couldn't tell.  I tried wiping everything up and drying it all, but I think the leak is slow enough that I couldn't get anything to start dripping to identify where the leak is.

Does anyone know which is the inlet and outlet side of the blue coolant valve?  I couldn't identify which end went into the water heater.  I couldn't follow the hose back far enough to tell.

Also, has anyone changed out these hoses before?  Is there a way to do it without pulling the water heater?

Thanks,
Benjie
Benjie, Ashley, Zoey, Fallon, and Lake
Round Rock, TX
In search of our next monster...

Re: Small Coolant Leak at Water Heater

Reply #1
Looks like it's probably coming from the one of the two hose clamp connections to the back of the water heater.  I would try to reach under there with a 5/16" driver and try to tighten them. Might have been induced by the cold weather.
There's an alternative access point: on the forward bulkhead there should be a hole (about 5" in dia.) that you might be able to reach in through the storage compartment although I think it might be too high up to reach these hoses as they towards the bottom of the water heater.
Another thing to do is tighten the packing nut on the blue valve stem - although it doesn't look like it's leaking there from the pictures.  I've had to do this on these valves on the past.
John Fitzgerald
1991 U300 (SAI) Side Aisle Island Bed 40'
Detroit 6V92 with Allison Retarder
Meridian (Boise), Idaho

Re: Small Coolant Leak at Water Heater

Reply #2
Benjie,
I don't believe that you would be able to change out that hose with out removing the water heater and possibly the water heater frame. My utility compartment is completely taken apart and I was going to change out those hoses, but they look to be in good condition and there is probably another 8 to 10 feet of hose (times 2 )once it gets through the bulkhead and goes over the transmission and differential before it gets to the engine, and is actually quite difficult to pull through the bulkhead even with all of the utility compartment guts removed. Spraying the hose with some WD-40 or wiping it down with same would make it easier to pull through and of course you'd be having to put a coupler in the hose to pull the new one in and that will be difficult as well (whose clamps would never make it through that bulkhead penetration), even with the water heater removed. It is a tight space to work in under the code between the bulkhead and the differential, even with it blocked up as high as I have mine. Difficult, but doable... also it is a challenge to identify for sure which hoes you're dealing with when working underneath the coach, and then to overcome the friction of all the hoses and cables pressing against it. It would help to identify exactly where on the engine or manifold that the motor eight clothes hooks up to, and then trace it back to the bulkhead. I think I will add some braided stainless hoses for the house hot water to make future removal and reinstallation easier when I get to that part of the project. Of course there maybe some differences in your setup that would make what you're looking to do possible... I hope so! Please be sure to post what you figure out and if I can think of anything else that may help I will chime in.
Of course as in the above post, making sure that the clamps on the hoses with a hook up at the water heater would be the very first step. Here an inspection camera or possibly a mirror would be of help to look at the orientation of the clamps and possibly even to spot the leak.
Don
I opened the water pump bay this weekend to find these pictures.  Has any one else had this issue?  It's a pretty slow leak as it had been sitting for about three weeks.  I looked for about 5 minutes, but could not find where the leak was originating.  I'm wondering if its at the bend in hose, but couldn't tell.  I tried wiping everything up and drying it all, but I think the leak is slow enough that I couldn't get anything to start dripping to identify where the leak is.

Does anyone know which is the inlet and outlet side of the blue coolant valve?  I couldn't identify which end went into the water heater.  I couldn't follow the hose back far enough to tell.

Also, has anyone changed out these hoses before?  Is there a way to do it without pulling the water heater?

Thanks,
Benjie
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Don & Tys
1999 U270 3602 WTFE #5402
Xtreme Stage 1 w/Headlight, Step Conversion, etc.
2009 Honda Fit Sport with Navi
Freedom is NOT "just another word for nothing left to lose"... with apologies to Kris Kristofferson

Re: Small Coolant Leak at Water Heater

Reply #3
Benjie, The leak at that shut off valve also occurs on mine.  I have tried tightening etc etc and nothing seems to stop it.  It is worse at the beginning of winter when I open the valve to allow coolant to flow to the dash heater.  When I had the WH out for other reason's I replaced the clamps to no avail.  It is my opinion that the leak on mine is from the packing on the valve itself, This type of valve cannot be repacked that I can see.  In the future when I have to make other repairs I am going to replace the valve with a ball type valve and better quality clamps..... In the meantime I mop up the coolant and swear at it. :-(
Gary B
BTW.  When I had to replace a cracked plastic nut on the back of the WH I used braided hose to replace the PEX.

Re: Small Coolant Leak at Water Heater

Reply #4
Mine has also leaked at the valve stem but stopped. It has been a very small amount though.

Mark Z
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Mark and Tanya
Milton , Florida
US Navy Veteran (DV)
1999 U270 Special 40' CAI , 2015 Jeep Wrangler Sahara

Re: Small Coolant Leak at Water Heater

Reply #5
Does anyone's set up look like mine?  I'm trying to determine which way the coolant flows.  I haven't been able to trace either hose to identify which side of the valve is engine side.
Benjie, Ashley, Zoey, Fallon, and Lake
Round Rock, TX
In search of our next monster...

Re: Small Coolant Leak at Water Heater

Reply #6
I like Gary's idea of replacing the valve with a ball valve.

You could also make up a longer barb on each end of the valve to allow two hose clamps (the same as we do on all below-waterline hoses on boats).

If it is leaking out the stem, you can try tightening up a little on the gland nut.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Small Coolant Leak at Water Heater

Reply #7
Benjie, The coolant hoses to the WH on mine look exactly like yours but I don't know which way the coolant flows.
I would suggest that you start it up and run on high idle at the same time either feeling the hoses or use a infrared thermometer to see which one gets warm first, that should be the engine end or the inlet to the WH.
Gary B

Re: Small Coolant Leak at Water Heater

Reply #8
Agree. Not a bad idea since the valve is probably original. Any suggestions to prevent a large coolant leak when removing the valve?

Best Regards,
Benjie

Benjie Zeller
(512) 587-4628
Benjie, Ashley, Zoey, Fallon, and Lake
Round Rock, TX
In search of our next monster...

Re: Small Coolant Leak at Water Heater

Reply #9
Benjie, Use a pair of vice grips to clamp off the hoses while you change the valve.
AND, I would plan on cutting off a Short piece of hose as it is probably pretty well aged and a NEW cut end will fit tighter on the new valve.

Gary B

Re: Small Coolant Leak at Water Heater

Reply #10
I tried that via the hand method but very difficult to tell since the distance is pretty short. Both sides warmed up about the same to me. One side might have been a LITTLE hotter but it wasn't enough for me to make a confident call. With the valve shut there's not enough heat transfer to make it all the way down the hose without any flow. I'll take another look see when I'm back at the coach to see if I can follow one of the hoses to the water heater.

Best Regards,
Benjie

Benjie Zeller
(512) 587-4628
Benjie, Ashley, Zoey, Fallon, and Lake
Round Rock, TX
In search of our next monster...

Re: Small Coolant Leak at Water Heater

Reply #11
Don,

Thanks for the input!  I'm hoping I can identify the point source of the leak.  I think its slow enough that its going to be difficult.  If I can reach back up in there and identify the right hose, I may try and replace the short hose from the valve to the water heater in hopes the leak is somewhere in that area.  Otherwise, since its not leaking much, I may just wait until water heater replacement needs to occur before tackling it.  A quick wipe and most of it is up. I estimate its maybe a quarter cup or something like that in 3-4 weeks time.

Regards,
Benjie

Benjie,
I don't believe that you would be able to change out that close with out removing the water heater and possibly the water heater frame. My utility compartment is completely taken apart and I was going to change out those hoses, but they look to be in good condition and there is probably another 8 to 10 feet of hose (times 2 )once it gets through the bulkhead and goes over the transmission and differential before it gets to the engine, and is actually quite difficult to pull through the bulkhead even with all of the utility compartment guts removed. Spraying the hose with some WD-40 or wiping it down with same would make it easier to pull through and of course you'd be having to put a coupler in the hose to pull the new one in and that will be difficult as well (whose clamps would never make it through that bulkhead penetration), even with the water heater removed. It is a tight space to work in under the code between the bulkhead and the differential, in with it blocked up as high as I have mine. Difficult, but doable... also it is a challenge to identify for sure which hoes you're dealing with when working underneath the coach, and then to overcome the friction of all the hoses and cables pressing against it. It would help to identify exactly where on the engine or manifold that the motor eight clothes hooks up to, and then trace it back to the bulkhead. I think I will add some braided stainless hoses for the house hot water to make future removal and reinstallation easier when I get to that part of the project. Of course there maybe some differences in your setup that would make what you're looking to do possible... I hope so! Please be sure to post what you figure out and if I can think of anything else that may help I will chime in.
Of course as in the above post, making sure that the clamps on the hoses with a hook up at the water heater would be the very first step. Here an inspection camera or possibly a mirror would be of help to look at the orientation of the clamps and possibly even to spot the leak.
Don
Benjie, Ashley, Zoey, Fallon, and Lake
Round Rock, TX
In search of our next monster...

Re: Small Coolant Leak at Water Heater

Reply #12
I bet it is the gland nut as Brett said as mine has a tiny one there too but nothing to worry about yet.
When I had the coolant replaced I should have thought of replacing the valve then but did not. Ah well my leak is maybe a spoonful in 6 months.
John H
Coachless, now use aircraft. 2003 Ford Travelair TC280 class C. Super shape. Just for 1 yr .
1994 Ford E350 ClassC,total renovation inside and out. Now sold.
2000 U295  36' Cummins 350 c/w Banks Stinger, Resonator upgrade,Solar, LED lites.Residential fridge with slide out pantry. Build 5674. Sold
ex 92 GV 022C ored Cummins. Sold
ex 95 GV240 cat 3116. Sold
2017 Mini cooper s & 2016 land Rover LR2 HSE  LUX.
jhaygarth@aol.com    SKP #130098
treat everyone as you would like to be.

Re: Small Coolant Leak at Water Heater

Reply #13
Benjie, I hate to admit what I did with my minor coolant leak so at the risk of looking foolish..... I took a SPAM can ( yeah, I like it fried with hashbrowns and scrambled ), cut down the side of it and slipped it under the valve, now that little bit of red coolant can be caught before it smears along the bay floor.  PLEASe, don't tell anyone else about this I would look like an idiot if this got out.. :) :)
Gary B

Re: Small Coolant Leak at Water Heater

Reply #14
Breeze clamps for better clamping.
Rick

Re: Small Coolant Leak at Water Heater

Reply #15
I was able to do a little more digging today at the coach and I think its the valve that's leaking.  There are some small drips directly below it, the paper tag attached to the valve has turned pick from soaking up coolant as it dripped from the valve, and I could see some moisture around the valve stem.

I think I'm just going to change out the valve to a ball valve.  I had my two year old with me and in the process of chasing him down, forgot to look at the size of the hose.  Anyone know what size ball valve I should purchase?  If not, I'll go measure the fittings sometime this weekend.
Benjie, Ashley, Zoey, Fallon, and Lake
Round Rock, TX
In search of our next monster...

Re: Small Coolant Leak at Water Heater

Reply #16
Benjie, it's likely the valve stem leaking. You can go to your local home improvement store in the plumbing section and get some graphite valve packing(looks like string), turn the valve off, remove the handle and gland nut wrap the packing around the stem reinstall the gland nut (tighten snug) and handle then open the valve and tighten the gland nut until any drips stop. You will not loose any coolant.
Bruce, Linda, and Macy
Zoey RIP 1/20/19
1999 U295 40' build #5400
2017 silver Jeep Wrangler, 1260 watts of solar on top
Moving around the country

 

Re: Small Coolant Leak at Water Heater

Reply #17
Actually, I would start by just tightening the gland nut with  a wrench.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020