Coolant leak at startup

TGKY

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Equipment
L4701DT
May 24, 2018
113
38
28
US
I have an L4701. I have had it at a farm I have doing some bush hogging and had left it sit for the last 5 days. We had major rain and a temp drop since I ran it last.
When I started it up today after it had run for about 5 minutes and I was doing my walk around I noticed antifreeze leaking from the top hose that runs from the radiator to the engine at the engine side.

I check the clamp for tightness and hose for leaks and the only thing I can come up with is somehow it got past the clamp even though it was tight. The last time I ran it I ran it hard, this is heavy mowing.
Coolant resivoir is just below the full line when cool.
I turned it off. Checked it for obvious sources and clamps and then turned it back on. After running for about 10 minutes the leak stopped completely and did not leak at all for the rest of the day.

Any ideas what’s going on? And what I need to do? I mowed for about 4 hours with no further leaking or fluid loss.

Im posting the pics for reference. This is after I had cleaned the fluid off so none visible.
 

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PoTreeBoy

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L35 Ford 3930
Mar 24, 2020
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WestTn/NoMs
I have an L4701. I have had it at a farm I have doing some bush hogging and had left it sit for the last 5 days. We had major rain and a temp drop since I ran it last.
When I started it up today after it had run for about 5 minutes and I was doing my walk around I noticed antifreeze leaking from the top hose that runs from the radiator to the engine at the engine side.

I check the clamp for tightness and hose for leaks and the only thing I can come up with is somehow it got past the clamp even though it was tight. The last time I ran it I ran it hard, this is heavy mowing.
Coolant resivoir is just below the full line when cool.
I turned it off. Checked it for obvious sources and clamps and then turned it back on. After running for about 10 minutes the leak stopped completely and did not leak at all for the rest of the day.

Any ideas what’s going on? And what I need to do? I mowed for about 4 hours with no further leaking or fluid loss.

Im posting the pics for reference. This is after I had cleaned the fluid off so none visible.
Anytime you suspect a leak, you need to remove the radiator cap and check the level in the radiator.
 

TGKY

Active member

Equipment
L4701DT
May 24, 2018
113
38
28
US
Anytime you suspect a leak, you need to remove the radiator cap and check the level in the radiator.
Thanks for mentioning that. I did do that before I re ran it the second time and before it got hot. There was antifreeze almost to the top of the radiator
 

North Idaho Wolfman

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Jun 9, 2013
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Sandpoint, ID
Loosen the clamp where it's leaking twist the hose back and forth a few times then retighten the clamp.
 
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TheOldHokie

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Apr 6, 2021
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windyridgefarm.us
I have an L4701. I have had it at a farm I have doing some bush hogging and had left it sit for the last 5 days. We had major rain and a temp drop since I ran it last.
When I started it up today after it had run for about 5 minutes and I was doing my walk around I noticed antifreeze leaking from the top hose that runs from the radiator to the engine at the engine side.

I check the clamp for tightness and hose for leaks and the only thing I can come up with is somehow it got past the clamp even though it was tight. The last time I ran it I ran it hard, this is heavy mowing.
Coolant resivoir is just below the full line when cool.
I turned it off. Checked it for obvious sources and clamps and then turned it back on. After running for about 10 minutes the leak stopped completely and did not leak at all for the rest of the day.

Any ideas what’s going on? And what I need to do? I mowed for about 4 hours with no further leaking or fluid loss.

Im posting the pics for reference. This is after I had cleaned the fluid off so none visible.
You sure it was coolant and not rainwater?

Dsn
 
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The Evil Twin

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L2501, LA526,
Jul 19, 2022
2,814
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Virginia
If it was coolant and not rainwater, it could be as simple as tightening that clamp. You mentioned that the temps dropped- that could cause shrinkage in more places than you think. As metals expand and contract you could have a leak where the clamp was just barely tight enough to begin with.
 
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NCL4701

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L4701, T2290, WC68, grapple, BB1572, Farmi W50R, Howes 500, 16kW IMD gen, WG24
Apr 27, 2020
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Central Piedmont, NC
That’s one thing about mine I was a bit surprised about. Had a small coolant leak that started at about 30 hours. Just a tiny amount and fan was blowing it all over the front of the engine so I was having a hard time identifying the source. It got steadily worse, which was actually a good thing because it got bad enough I was able to remove the loader, remove the side panels, wash the engine, let it dry overnight, and locate the source the next morning. The upper radiator hose clamp was loose. While I had it open for inspection I went over it and checked every clamp I could find. About half of them were loose. Tightened them all. No more issues.

I’ve since heard this is why so many manufacturers use spring clamps instead of the worm drive type clamps. Spring clamps automatically tighten as needed. Don’t know if that’s the real reason for spring clamps or not but it does make sense.
 

The Evil Twin

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L2501, LA526,
Jul 19, 2022
2,814
2,825
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Virginia
I think the reason so many use spring clamps is assembly speed. The definite added bonus is that they are self tensioning.
 

tinkerwitheverything

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Equipment
bx2370-1
Jun 3, 2015
319
72
28
Manitoba
If what was mentioned above solves your problem good. If not then remove the hose and clean both surfaces . Overtime it will create a White /greenish/blueish film between the hose and housing . Of course this is why you have a leak due to buildup of scale.
 

ItBmine

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Equipment
B2620, RTV-X1100C
Jan 21, 2014
1,375
378
83
Canada
Have the same problem with my RTV-X1100C since the day it was new. I have been chasing coolant leaks all over it. I tightened all the clamps but as soon as it cools off overnight, it has a tiny puddle in the belly pan. I can see where it's leaking and those clamps are tight. Never leaks hot.

I might have to do what Wolfman said....loosen the clamps and reset the hoses.
 

TGKY

Active member

Equipment
L4701DT
May 24, 2018
113
38
28
US
Thanks everyone. I’ll report back based on results from the advice above. i did want to mention I’m sure it’s coolant based on the color.
thanks again
 
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