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Topic: Red fluid leaking from passanger rear, near radatior - 2003 U320 / 450 Cummins (Read 738 times) previous topic - next topic

Red fluid leaking from passanger rear, near radatior - 2003 U320 / 450 Cummins

I noticed a small puddle of red fluid (~1/8th of a cup) under the passenger side rear of the coach (engine/radiator) when dumping this morning. 

We drove a short way to the nearest town to get wifi to research the problem.  The engine and transmission temps were all normal during the 20 min drive.  Now there is no leaking that I can see. 

Not sure if it had anything to do with anything, but I noticed it after bleeding the air lines (while the engine was idling).  The coach has been sitting for 3 days and there was nothing leaking the whole time.

I will check for fluid in the cooling system (black box on top right of the engine bay - has radiator cap) when it cools down.  After which I will start up the engine and check the transmission fluid level.

Looking around the engine bay and underneath the engine/trans with a flashlight and I couldn't see any leaks.

Any ideas?  Red is transmission fluid right?  I took a pic of the leak and can post it up if it's of any value.
2003 U320 38' tag
2003 Green Jeep Wrangler

Re: Red fluid leaking from passanger rear, near radatior - 2003 U320 / 450 Cummins

Reply #1 –
You may have red coolant.  If the puddle was close to the side of the coach on the pass side just behind the drive wheels it could be radiator fluid.  Mine radiator has a rubber piece under the radiator and it was dripping off the front edge of it.
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN

Re: Red fluid leaking from passanger rear, near radatior - 2003 U320 / 450 Cummins

Reply #2 –
Most likely, it is coolant. They typically have the red extended life coolant from the factory and if you are low, you will notice it first in the plastic expansion tank to the right of the black metal remote mounted radiator reservoir tank. The expansion tank should have a full hot and cold mark on it respectively and should be inspected as part of every pre-trip. The radiators are bolted along the sides and often times, the small leaks can be stemmed by carefully snugging up each of the bolts that you can get a wrench on. The fan motors typically use SAE Grade 15w40 motor oil and can be checked via the dip stick in reservoir on the street side of the engine.
Don
Quote from: coloradomtn –
I noticed a small puddle of red fluid (~1/8th of a cup) under the passenger side rear of the coach (engine/radiator) when dumping this morning. 

We drove a short way to the nearest town to get wifi to research the problem.  The engine and transmission temps were all normal during the 20 min drive.  Now there is no leaking that I can see. 

Not sure if it had anything to do with anything, but I noticed it after bleeding the air lines (while the engine was idling).  The coach has been sitting for 3 days and there was nothing leaking the whole time.

I will check for fluid in the cooling system (black box on top right of the engine bay - has radiator cap) when it cools down.  After which I will start up the engine and check the transmission fluid level.

Looking around the engine bay and underneath the engine/trans with a flashlight and I couldn't see any leaks.

Any ideas?  Red is transmission fluid right?  I took a pic of the leak and can post it up if it's of any value.
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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: Red fluid leaking from passanger rear, near radatior - 2003 U320 / 450 Cummins

Reply #3 –
Quote from: Roger & Susan in Home2 –
You may have red coolant.  If the puddle was close to the side of the coach on the pass side just behind the drive wheels it could be radiator fluid.  Mine radiator has a rubber piece under the radiator and it was dripping off the front edge of it.

Yeah, the leak appears to coming from the rear of that rubber strip that sits under the radiator.
2003 U320 38' tag
2003 Green Jeep Wrangler

Re: Red fluid leaking from passanger rear, near radatior - 2003 U320 / 450 Cummins

Reply #4 –
Quote from: Don & Tys –
Most likely, it is coolant. They typically have the red extended life coolant from the factory and if you are low, you will notice it first in the plastic expansion tank to the right of the black metal remote mounted radiator reservoir tank. The expansion tank should have a full hot and cold mark on it respectively and should be inspected as part of every pre-trip. The radiators are bolted along the sides and often times, the small leaks can be stemmed by carefully snugging up each of the bolts that you can get a wrench on. The fan motors typically use SAE Grade 15w40 motor oil and can be checked via the dip stick in reservoir on the street side of the engine.
Don

Thanks guys.  The radiator reservoir tank is about 1/2 way between the hot and cold mark when the engine is cold.  So I guess it could be overfull?  Maybe it's overflowing and that's what I saw on the ground?  I checked the fans and couldn't see any leaks.

Anyway we are about to get underway again.  Not sure when we will next get internet, so thanks a ton for the help everyone.



2003 U320 38' tag
2003 Green Jeep Wrangler

Re: Red fluid leaking from passanger rear, near radatior - 2003 U320 / 450 Cummins

Reply #5 –
When I first got my coach it was leaking from the radiator bolts. Tightened up what I could reach and hasn't leaked since.


Larry
Larry Warren
1996  U320 36' SBID "Lola" sold 2020
Build #4970
Motorcade #18318

Re: Red fluid leaking from passanger rear, near radatior - 2003 U320 / 450 Cummins

Reply #6 –
I have found loose radiator hose clamps , if they are just a little loose, they will leak when the engine gets cold... Sometimes all it takes is a half a turn on the clamp and the leak is gone ! The low coolant light will come on when the coolant gets too low... that is the switch at the bottom of the metal tank with the radiator cap on top.... The overflow hose from that container to the plastic recovery tank can also get a small hole in it from rubbing....The metal tank should be right full, the plastic recovery tank has a cold full mark...
Good Luck,
Safe Travels
Dave
2001 U320 40ft
Build #5867
2003 Tracker
VE7DOD

Re: Red fluid leaking from passanger rear, near radatior - 2003 U320 / 450 Cummins

Reply #7 –
The two radiator connections are at the rear end. They should have constant tension clamps.  Mine was leaking somewhere in/on the radiator itself.  Some days there would be a bit others not.  I don't like leaks.  I had the radiator repaired.  If Inhad been in TX I would have replaced it.  You have 16 gal of coolant so even a quart won't make any difference.  Get it checked out.
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN

Re: Red fluid leaking from passanger rear, near radatior - 2003 U320 / 450 Cummins

Reply #8 –
My 2003 U320 had a leak in the AquaHot, which circulates antifreeze. 

Re: Red fluid leaking from passanger rear, near radatior - 2003 U320 / 450 Cummins

Reply #9 –
90% chance it is a seep from the end caps on the radiator if you have the long life red coolant. There are bolts on the end caps you can tighten if you can get to them.

And there is nothing wrong with using Barrs stop leak in the radiator to stop "seeps".  Even FOT and MOT do so.

Search "Barrs" on the forum. This link "might" work: https://www.foreforums.com/index.php?action=search;sa=results
Dan - Full timing since 2009
2003 U320 40' Tag 2 slide