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Topic: "rotting" area on radiator (Read 967 times) previous topic - next topic

"rotting" area on radiator

I'm looking for a better word, but a section of fins on the engine radiator behind one of the hydraulic fan motors crumbles to the touch.  I went into service because a seal on the fan motor is leaking and I am being told that it cannot be rebuilt and FT is the only source for a new one.  Meanwhile the tech shows me the radiator itself needs work.

We can't find any leak in the radiator now but I can't imagine it will hold for long.  The problem area is at least 3 inches in diameter and there might be other areas as well.

Any ideas short of replacement?
Larry Rubin
2004 U295 38' build 6278
2014 Jeep Cherokee

Re: "rotting" area on radiator

Reply #1 –
Larry,

It depends on what is "rotting"  The radiator is made up of tubes that carry the coolant and fins attached to them that help dissipate the heat.  If it's just the fins that have corroded and the tubes are OK then you can ignore it.  Just wash it down to get whatever is causing the corrosion off.  If only a couple of the tubes are corroded then it is possible to seal off a few without affecting the radiators capacity unless you are in Death Valley in the summertime.  Have a shop that does not want to sell you a radiator look at it.

Keith
Keith, Joyce & Smokey the Australian Cattle Dog
1995 U320 SE Extreme 40' WTBI Build # 4780, with a Honda CR-V hopefully still following behind.
Motorcade # 17030
FMCA # F422159

Re: "rotting" area on radiator

Reply #2 –
What he said! It sort of sounds like something nasty and acidic found its way to that section of radiator. If your radiator is like the one in our u280, it's made of copper, which points to some manner of galvanic corrosion as copper doesn't react with most acids. I'd wash the area down really well, maybe even with watered down baking soda, and spray black rustoleum on it. Maybe installing a sacrificial zinc anode ( any marine supply store) would be a good idea. If it wears away in weeks or months it will tell you to find a ground fault before it causes any more damage. I bet Brett can shed more and better light on this. I've never seen radiator "rot" like this before.
Jay
1989 U280 SE, 36', 3208T Cat, build 3292

Re: "rotting" area on radiator

Reply #3 –
Larry, I have seen radiator fins rot like that, as others have said something corrosive may have gotten on it like road salt. While it most likely is not a problem now it most certian;y will be sooner than later. Do a search on the forum here forum (hyd fan motor repair) there is a hyd company in WVA that will rebuild your fan motor, I don't remember the name or phone #. While it may take a little while with shipping and all it's going to be a bunch cheaper. if you have time to wait.
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: "rotting" area on radiator

Reply #4 –
here you go. Mr. Wayne Beckett
J & S Hydraulics, Inc
785 Airport Road
Sutton, WV 26601

Office: 304-765-7008
Cell: 304-619-4776
FAX:304-765-0109

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: "rotting" area on radiator

Reply #5 –
Road salt is the cause.  Saw it on a buddy's '95 U320 - he's from the Missouri area and is a fulltimer that travels back there during the holidays.  He had it real bad.  Shows up on the fan side of the radiator.  We were both astonished at how bad it was.  He had no issues with overheating and there were no radiator leaks at all; multiple long lengths (12" or so) of unsupported radiator tube where the fins had turned to dust and were just gone.  Outside face of radiator looked fine.  We pulled the radiator ourselves and he took it to a local shop that replaced the core.  Boat places sell this stuff called Salt-X that is supposed to be good at removing it.  Assuming you're not driving on salted roads, the damage may have been done long ago and the salt maybe long washed away.  I would rinse with water (and Salt-X if you can) and monitor it.
John Fitzgerald
1991 U300 (SAI) Side Aisle Island Bed 40'
Detroit 6V92 with Allison Retarder
Meridian (Boise), Idaho

Re: "rotting" area on radiator

Reply #6 –
And many Blue Beacon Truck washes use a undercarriage rinse called Salt-Away Home Page.  I always get the undercarriage rinsed when I have traveled on roads that have received anti skid treatment.
1994 U225
build #4514

Re: "rotting" area on radiator

Reply #7 –
Lots of great help - thanks.

Is there any way other than visual inspection to tell if the tubes are close to failing?
Larry Rubin
2004 U295 38' build 6278
2014 Jeep Cherokee

Re: "rotting" area on radiator

Reply #8 –
Larry, If the tubes are not leaking you are probably OK.  The fins act as heat sinks to carry off the heat from the tubes.  If enough ( I don't know how many ) of the tubes are exposed then you would probably get an overheat problem.  Go by a local radiator shop and see what they tell you about it, they may have more insight than the mechanic since they deal with radiators every day.
Gary B

Re: "rotting" area on radiator

Reply #9 –
Quote from: Larry Rubin –
Lots of great help - thanks.

Is there any way other than visual inspection to tell if the tubes are close to failing?
I think the first sign is the fins become detached from the tubes.  If you press on the fins with your finger (or small screw driver) you'll see that the fins easily move and are not attached to the tube.  Once detached the fins are no longer providing much cooling and you only have the tube surface area doing the cooling work.
John Fitzgerald
1991 U300 (SAI) Side Aisle Island Bed 40'
Detroit 6V92 with Allison Retarder
Meridian (Boise), Idaho

Re: "rotting" area on radiator

Reply #10 –
Larry,

As you can't see inside the tube you can only inspect the outside for corrosion.  If the tube looks good I would not worry too much.  A pressure test can also detect leaks and carefully over-pressurizing the radiator will let you know if it's about to let go.  This can be done by any mechanic with one of these:

Keith
Keith, Joyce & Smokey the Australian Cattle Dog
1995 U320 SE Extreme 40' WTBI Build # 4780, with a Honda CR-V hopefully still following behind.
Motorcade # 17030
FMCA # F422159

Re: "rotting" area on radiator

Reply #11 –
I my case, about 40%-50% of the finning was missing but no leaks.  Just started to become hard to cool down on long grades in Arizona. I figure most of my fins were both salt and sand blasted as I do a lot of driving in unpaved desert roads and the cooling fans really move that abrasive sand around like a sand blaster.
JON TWORK KB8RSA
Full Time RVer (10+ Years) & Dedicated Boondocker
Retired, Unemployed, Homeless Transients
1996 Foretravel U270-36 w/24' Timberwolf Trailer
I firmly believe that tomorrow holds the possibility for new technologies, astounding discoveries, and a reprieve from my remaining obligations.
Welcome to WeRV2 (Under Construction)
Find Jon: Via Satellite Tracker Datastorm Users
The Second Amendment is in place in case they ignore the others.

Re: "rotting" area on radiator

Reply #12 –
Wow - 40-50% fins missing and the thing still works!
Larry Rubin
2004 U295 38' build 6278
2014 Jeep Cherokee