Community Forums

RVPioneer · 11-27-2018, 06:20 PM

Our coach has developed a hydraulic leak. At the very rear of what I believe is the hydraulic oil cooler is an aluminum box or end cap approximately 3" x 5" with a hydraulic hose connected in the center. A tag above the hose reads, 45925 Performance TAC. This is below the radiator and just forward of the muffler.

The leak appears at the edge of the cap, directly to the right of the hose when viewed with ones head near the muffler. Yes, the engine is running. The leak could be starting somewhere else but by the time I start the engine and get to the back it's too late to know. My neighbor, who used to repair helicopters and takes cars apart and puts them back together in his spare time, should be able to look at it tomorrow or the next day. I haven't measured the rate of fluid loss but it is similar to waiting for the last ounce to leave a quart bottle of oil.

The leak started on the last day of a trip and we noticed it at our final fuel stop. It was a slow drip and the toad had a nice exterior lube, so it must have been happening for quite a few miles. After driving the coach around in the driveway it has developed into a more significant leak. I added just over a gallon to the reservoir. It's a 14 mile drive to the service shop and leaving a trail of 15W-40 or running high and dry are not the preferred options. Ideally, I'd like to patch it up somehow for the drive.

Now the question. Could there be a pinhole in the aluminum or is this coming from somewhere else? The shaft seal seems to be the usual suspect.

Thanks,
Bob

Old Scout · 11-28-2018, 06:07 AM

...a picture would be worth a 1000 words....kind of sounds like the hydraulic fluid cooler unit--kind of unusual to fail on end cap unless it was bumped at some point--like running over a curb????. Try using search on this form--eg. "f104/hydraulic fluid cooler". Believe there is/are replacement source[s]….

RVPioneer · 11-28-2018, 01:41 PM

Not sure if the pic is attached. The weld is cracked exactly where I described the leak. Losing a quart a minute. Headed to the shop to show them photos and discuss repair options.

RVPioneer · 11-28-2018, 07:13 PM

I removed the oil cooler this afternoon. Tomorrow morning I'll take it to Oregon Light Truck and RV, they'll send it up to Radiator Supply House for analysis. Probably looking at having a new unit made.

Removal was pretty simple, just need a 1 1/2" wrench for the hoses. Once out it was easy to verify that the oil was not leaking from any other areas. Loose hoses have freezer bags zip tied over the open ends, new filters will be going in the reservoir.

We can rule out curb jumping, but there could be any number of explanations for this failure. I'm inclined to believe that it is a manufacturing defect, either a poor weld or a weld that was compromised by impurities on the material. Or a solar flare. Whatever the case it may be something for 2005MY owners to keep an eye on.

I'll follow up when the repair is complete.

RVPioneer · 11-30-2018, 02:07 PM

This is a photo of the crack on the oil cooler.

TriMoot · 11-30-2018, 02:23 PM

Wow..that weld to me looks like a good weld, although I admit, this isn't my area of expertise, I should let other folks chime in that actually know about such things.

I would love to hear what people think that caused this failure. Was the weld too deep? Not deep enough? Too much pressure? Interesting.

Standing by to hear what the pro's think, and thanks for sharing. I always learn stuff here.

Jeep401 · 11-30-2018, 03:46 PM

I'm no expert either, but it can't just be drill stopped, V'ed out and rewelded?

c_oneil · 12-01-2018, 08:02 AM

You may want to review this old thread:
http://www.irv2.com/forums/f104/alpi...re-105120.html

It is a review of ruptured oil cooler tanks and leaks in welds that happened to '07/'08 coaches. There was a possible issue of a clogged check valve in the system and a suspect WRV over pressure by pass fix plus other causes. I think your '05 has a different pump setup but there could be issues you would want to be aware of with the tank pressure.

Janet and Todd · 12-01-2018, 08:06 AM

Hope you can remove this tank to repair it because if you weld while it's installed, you risk blowing your Vansco and/or other electronic components (if installed).

RVPioneer · 12-01-2018, 08:49 AM

Here's a shot of the repaired cooler. Today's goal is to reinstall it and head down the driveway to park it in the new RV garage. Of course it's 35° and raining. I'll be out of town for the next 2 weeks.

Thanks for the link to the thread regarding a similar problem. I'll get into that some more when I get back.

Yes, it was removed for the repair.

RVPioneer · 12-01-2018, 05:26 PM

Successful install. Tucked away for the winter.

Jeep401 · 12-01-2018, 05:43 PM

Quote:

Originally Posted by RVPioneer

Successful install. Tucked away for the winter.

Very nice. My cover started going up Thursday, not nearly as nice as yours, but cover never the less.

RVPioneer · 12-05-2018, 09:06 AM

Quote:

Originally Posted by c_oneil

You may want to review this old thread:
http://www.irv2.com/forums/f104/alpi...re-105120.html

It is a review of ruptured oil cooler tanks and leaks in welds that happened to '07/'08 coaches. There was a possible issue of a clogged check valve in the system and a suspect WRV over pressure by pass fix plus other causes. I think your '05 has a different pump setup but there could be issues you would want to be aware of with the tank pressure.

Carter,

I finally had time to read through the thread that you linked earlier. While I believe the set up and cooler on our 2005’s is different than the 2008’s, the failure was nearly identical. Now that the coach is drivable I am going to take it to the shop and have them conduct the pressure tests as mentioned in the other thread and evaluate the entire hydraulic system for potential problems.

Because of the unexpectedly quick repair, I did not have new reservoir filters on hand so I’ll have those installed as well. I’ll also ask about having sensors installed with a read out in the cockpit.

Thanks again for the information.

Bob

RVPioneer · 12-05-2018, 09:13 AM

Quote:

Originally Posted by Jeep401

Very nice. My cover started going up Thursday, not nearly as nice as yours, but cover never the less.

Thank you. I had to get it done before the cost of the building exceeded the value of the coach. Quite a project being that it’s 500’ from the house (power) and on unlevel ground.