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Topic: Losing coolant - '01 U320 ISM450 (Read 570 times) previous topic - next topic

Losing coolant - '01 U320 ISM450

We have lost a half gallon of coolant in 1000 miles since leaving MOT after taking delivery in October. I think this is an excessive amount. Is it?
Royce & Denise, MC #17410
'01 U320 4220 ISM450 Build #5895 SOLD
Toad: '10 Honda CR-V

Travel makes one modest. You see what a tiny place you occupy in the world. - Gustave Flaubert

Re: Losing coolant - '01 U320 ISM450

Reply #1 –
I seemed to have lost coolant like that, after opening and messing with the coolant system doing the motor aided new hot water heater drain down and refill.  I finally stopped needing to top to the fill line, and all has been good since.  On my last coach, same thing for the first couple of months, and then it too stopped showing any losses.  I think on that coach the messing with the system and the addition of the extra radiator at the front of the coach, just took a long time to purge all the air.

Question might be asked, has the coolant system been drained and the coolant replaced in the last few months?  Lots of hoses for air to be purged from, and your 1,000 miles has maybe done that purging.
Dave Cobb
Buckhorn Lake Resort The Club, #6202, Kerrville TX
check the map.  I do rent it out when I am traveling!
2001, U320, 36' #5887, in Kerrville, FT Club #17006, (7/23 to present)
2024 Jeep Grand Cherokee L, Summit, white
EX: 98 U295, 36' #5219, (mid door), (4/13-10/23)
EX: 93 U225, 36' (4/11 to 4/13)

Re: Losing coolant - '01 U320 ISM450

Reply #2 –
Royce,
That seems like a lot. We haven't added any to ours for about 3000 miles. We haven't had our system open sense we replaced our coolant filter. Even after that we didn't add more than a cup of antifreeze after we ran it a couple of hundred miles.

Pamela & Mike
Pamela & Mike 97 U 320

"It's not what happens to you, but how you react to it that matters."

Re: Losing coolant - '01 U320 ISM450

Reply #3 –
To clarify, the coolant is actually leaking onto the ground under the overflow tank. How much of this is acceptable? Any? Is this a problem?
Royce & Denise, MC #17410
'01 U320 4220 ISM450 Build #5895 SOLD
Toad: '10 Honda CR-V

Travel makes one modest. You see what a tiny place you occupy in the world. - Gustave Flaubert

Re: Losing coolant - '01 U320 ISM450

Reply #4 –
Royce,

Look for a crack in the bottom of your overflow tank.  Check to see if the hose clamp on the bottom is loose. While you are there check the hose to see if it is cracked right at the place where it connects to the overflow tank. Replace as needed. Our hose is 5/16" hose and it takes 4'.  You shouldn't be loosing any out of that spot.

Pamela & Mike
Pamela & Mike 97 U 320

"It's not what happens to you, but how you react to it that matters."

Re: Losing coolant - '01 U320 ISM450

Reply #5 –
That is too much. LOok for a crack on the black tank and try to trace where it is coming from. If you see it under the tank side there is that but also look in the center of the coach. It could be the water pump weeping. I had that happen and had to change mine out last year.
2025 Wanderbox Outpost 32 on F600 Expedition Motorhome
2015 Born Free Royal Splendor on Ford 550 nonslide version  for sale
Former Coaches  covering. 360,000 miles
1999 34 U270
2000 36 U320
2001 42' double slide U320
2018 Jeep Rubicon

Re: Losing coolant - '01 U320 ISM450

Reply #6 –
Check to see if you have the correct radiator cap with gasket . At one time I had the cap without a rubber gasket and I would lose about half a cup of antifreeze every time I drove.
joseph gambaro
1999 U295 36'

Re: Losing coolant - '01 U320 ISM450

Reply #7 –
Had a
Quote from: BamaFan –
To clarify, the coolant is actually leaking onto the ground under the overflow tank. How much of this is acceptable? Any? Is this a problem?
Had a leak in my tank, called Foretravel and got a replacement. Not a big deal to replace.

Roland
1993 U280 4341
2010 Jeep Liberty
The Pied Pipers

Re: Losing coolant - '01 U320 ISM450

Reply #8 –
Quote
Look for a crack in the bottom of your overflow tank.
Good possibility. That was my problem. Couldn't even see the crack. All fixed with a new tank which I got from Foretravel. Turns out, they are still using the same tank.
jor
93 225
95 300
97 270
99 320

Re: Losing coolant - '01 U320 ISM450

Reply #9 –
Replaced my tank this summer.  Seems the MTF is about the same fore these units.
2025 Wanderbox Outpost 32 on F600 Expedition Motorhome
2015 Born Free Royal Splendor on Ford 550 nonslide version  for sale
Former Coaches  covering. 360,000 miles
1999 34 U270
2000 36 U320
2001 42' double slide U320
2018 Jeep Rubicon
 

Re: Losing coolant - '01 U320 ISM450

Reply #10 –
If the overflow tank is too full when cold, it could overflow to ground.  We extended the overflow hose into a gallon container so we would know if during a big expansion we are losing coolant (and allow recovery).