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Author Topic: Coolant leak when it is cold out  (Read 7065 times)

Offline Kitt

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Coolant leak when it is cold out
« on: November 10, 2012, 07:26:26 PM »
Hi all.

My 05 was new to us this year and we are just now getting some nights below freezing. I noticed yesterday that some coolant was dripping from the engine in a few spots. On closer inspection it was a very very slow drip (an ooze?) from a bunch of the flexible hoses. I don't think the coolant froze at all to cause this issue - it is green and not icy though I did not test it with a hydrometer or refractometer.

I went out today and tightened up the clamps and hope that takes care of it for now if the leak was either from the hose not being flexible enough in very cold weather and/or the metal pipes shrinking just a little bit.

Is this "normal" and would I be better off using constant torque clamps on the hoses, or are there better hoses to use, or something else I'm not thinking of?

Thanks.
1977 Eagle model 05
8v71, Allison HT740D

Offline luvrbus

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Re: Coolant leak when it is cold out
« Reply #1 on: November 10, 2012, 07:30:07 PM »
If you have silicone hoses the constant torque clamps are a must, for me the Gates Green Stripe hose is a tough product to beat at about 1/2 the cost of silicone
« Last Edit: November 10, 2012, 07:41:18 PM by luvrbus »
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Offline gus

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Re: Coolant leak when it is cold out
« Reply #2 on: November 10, 2012, 08:05:23 PM »
More leaks is pretty much normal for coolant in cold weather, shrinkage and all that stuff.
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Offline Mike in GA

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Re: Coolant leak when it is cold out
« Reply #3 on: November 11, 2012, 06:53:55 AM »
The metal bibs that your coolant hoses slip onto will shrink/draw up a little in cold weather. You will notice that a leaky hose on a cold morning is often a dry hose after a run down the road and after the thermostats open. As said above, the best solution is spring clamps or constant torque clamps. Much more expensive but worth it.
Mike in GA
Past President, Southeast Bus Nuts. Busin' for more than 15 years in a 1985 MC 96a3 with DD 8v92 and a 5 speed Allison c/r.

Offline eagle19952

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Re: Coolant leak when it is cold out
« Reply #4 on: November 11, 2012, 08:40:49 PM »
i like the spring loaded type clamp, one thing i have found to help is to warm up the hoses with a heat gun and then re-tighten.
Donald PH
1978 Model 05 Eagle w/Torsilastic Suspension,8V71 N, DD, Allison on 24.5's 12kw Kubota.

Offline buswarrior

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Re: Coolant leak when it is cold out
« Reply #5 on: November 11, 2012, 08:50:18 PM »
With all of this said, simply tightening the old style clamps when it gets cold also works just fine.

For those busnuts on a budget, don't rush out thinking you have to buy the really nice constant torque clamps.

You will, more than likely, have higher priorities for spending cash.

happy coaching!
buswarrior

Frozen North, Greater Toronto Area

Offline Kitt

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Re: Coolant leak when it is cold out
« Reply #6 on: November 12, 2012, 10:17:21 AM »
Yes, plenty more calling for cash. This year for sure I will just be tightening the clamps. Thanks for everyone's input!
1977 Eagle model 05
8v71, Allison HT740D

Offline luvrbus

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Re: Coolant leak when it is cold out
« Reply #7 on: November 12, 2012, 10:23:37 AM »
Yea but BW if he has silicone hoses he keeps tightening the clamps he will spend money for more than clamps
Life is short drink the good wine first

Offline bobofthenorth

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Re: Coolant leak when it is cold out
« Reply #8 on: November 12, 2012, 06:30:18 PM »
I picked up 4 constand torque clamps from a DD dealer in Regina about a month ago now.  I don't remember exactly what they were but I was astonished how little they were.  I'm thinking maybe $4 or $5 per each for 2.25" clamps.  Not worth messing with IMHO, if that's what it takes. 
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Offline Lin

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Re: Coolant leak when it is cold out
« Reply #9 on: November 12, 2012, 07:14:40 PM »
No doubt, better clamps are better.  However, I have not gotten to doing that yet.  I do double clamp anything that I am concerned about though.
You don't have to believe everything you think.

Offline Dave5Cs

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Re: Coolant leak when it is cold out
« Reply #10 on: November 12, 2012, 07:31:55 PM »
I was told by a guy at Valley to put silicon on the end of any casing and let it dry before you put on the hose, that way they don't eat through the silicon hose layer by layer.

Dave5Cs :D
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Offline Ace

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Re: Coolant leak when it is cold out
« Reply #11 on: November 12, 2012, 08:15:00 PM »
I found that a simple fix for a simple "cold" leak is to just bring the unit up to operating temp and tighten all connections!
This happened to me last year and this advice obviously worked because no leaks since!


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Offline sledhead

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Re: Coolant leak when it is cold out
« Reply #12 on: November 13, 2012, 04:50:24 AM »
What Ace said .Worked for my silicone hoses                 dave
dave , karen
1990 mci 102c  6v92 ta ht740  kit,living room slide .... sold
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Offline luvrbus

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Re: Coolant leak when it is cold out
« Reply #13 on: November 13, 2012, 05:02:30 AM »
I don't think he ever told us what hoses he has on the bus,I use the green stripe Gates and the clamp torque wrench from a plumbing supply and never have leaks I can go from 100 degrees in Phoenix to below freezing in Idaho the best advice is to buy good clamps the HF clamps don't cut it
Life is short drink the good wine first

Offline Kitt

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Re: Coolant leak when it is cold out
« Reply #14 on: November 16, 2012, 06:40:18 PM »
I don't know what brand the hoses are that I have - there isn't any writing on them and no stripes. They look like similar to the EPDM hoses with a fabric outer wrap. And the clamps are the standard (cheap?) kind - nothing fancy.

After tightening the clamps a few days ago there haven't been any more leaks despite all of the below freezing / above freezing cycles we have had lately.
1977 Eagle model 05
8v71, Allison HT740D