Electrolysis

[darbyjudy]

I have a 2004 Gulfstream Sunvoyager with three slides. On the two living room slides there is electrolysis on the end of the slide out. It started as some small bubbles in the paint toward the bottom of the end of the slideouts . I had one of them repaired and it was electrolysis in the thin aluminum. Has anyone else had this problem and what was the fix?

[RV Wizard]

Be sure to check for an electrical hot skin problem. Be sure the coach frame, body and all electrical equipment is properly grounded to the equipment ground conductor on the shore power cord. Also be sure you do not have a partially shorted heating element in refrigerator or water heater. Let us know what you find.

[darbyjudy]

Mike how can I check for that problem?

[wa8yxm]

How to check for hot-skin problem (electrical hot)

Voltmeter, high impedance type (most digitals qualify)

Skin where problem is cocerned gets one probe

Chassis gets other probe

Check both AC and DC, Proper reading is ZERO VOLTS

NOTE: also check chassis to earth if you can..

[Jim Stewart]

I see you live in New Port Richey, Florida. Are you sure it's not just galvanic corrosion. For galvanic corrosion to exist, you need two dissimilar metals and an electrolyte. Sea water in itself can be an electrolyte. Or, salt in the air with condensation. I believe that is the nature of your problem.

I know what they do on boats, they use sacrificial anodes. I do not know what to do on a MH to fix the problem.

[darbyjudy]

Jim yes we are located in New Port Richey but live several miles from the coast. As far as I know this motor home has never been near salt water. This problem started several years ago and it has gotten a little worse. I am not sure how to make the repair. It is a very thin sheet of aluminum over wood. I guess I could try and find some thin aluminum and cut the old out and install new, and repaint to match. I will just watch and see how it progresses. I don't think it is anything to worry about except how it looks. Right now it is just a little bubbly under the paint on the aluminum.

[Jim Stewart]

Quote:

Originally Posted by darbyjudy Jim yes we are located in New Port Richey but live several miles from the coast. As far as I know this motor home has never been near salt water. This problem started several years ago and it has gotten a little worse. I am not sure how to make the repair. It is a very thin sheet of aluminum over wood. I guess I could try and find some thin aluminum and cut the old out and install new, and repaint to match. I will just watch and see how it progresses. I don't think it is anything to worry about except how it looks. Right now it is just a little bubbly under the paint on the aluminum.

Is is amazing how far that salt air can travel. Do you know if there is any moisture that could be getting between the aluminum and wood? Does the aluminum butt up against another piece of metal that may be steel? Either case with a high salt content in the air could cause the bubbles.

I have a little of the same problem on the edge of the ring that goes around the outside door for my water heater. I believe that water from rain may blow in the vent and pools in the corner against the ring where it is caulked to the wall.

We live in Florida by the coast, and my DWs car that is always parked in the garage has a spot at the edge of the hood which is doing the exact same thing. I believe that the water runs down the sloped hood and sits at the underside of the edge and with the salt in the air, over time, has worked it's magic. The car is 4 years old and never seen salt roads!

[Swannee]

I have a 2006 GS Endua. The large slide out at the drivers door end, developed lumps under the paint touching the largest one "quater size" paint flaked off revealing oxidation,and revealed wet underlaymant.
Checked for leaks all looked good,at that time, however
Oxidation spots continued to develop.
Slide out definatly has a leak. Removed all caulking and found several leaks. Repaired a multitude of holes in the end plate. Drilled weap holes at the bottom and continue to get deminishing moisture from them as slide dries out.
You need a moisture meter to detect for leaks inside under liners abd paneling meter works on conductivity between the probes. You will have to poke 2 small holes with the probe to locate moisture.
Good Luck