I'm dealing with a frustrating issue on my 2015 Fleetwood Expedition 40X where the small frameless window above my kitchen sink has completely separated from the metal crank arm mechanism. During my last camping trip, I noticed the window was loose and flapping around in the wind, which was both annoying and concerning. When I got back and examined it more closely, I can see that the bond between the glass and the crank mechanism has failed entirely.
I know I need to reattach it with some kind of adhesive, but I'm overwhelmed by all the different options out there. I've seen mentions of products like 3M Windo-Weld and various Sikaflex formulations (like 221, 255, 291), but I'm not sure which one is specifically designed for this type of repair. I also want to make sure I do this right the first time since it's such an exposed area that takes a beating from weather and road vibration.
What's the best adhesive for rebonding a frameless glass window to its crank mechanism, and what's the proper process to ensure it holds up long-term? I want to make sure I clean the surfaces properly and give it adequate curing time before I start operating the window again.
Frameless window separated from crank arm needs rebonding with urethane adhesive. Clean surfaces, apply 3M Windo-Weld or Sikaflex 255, clamp, and cure 24-48 hours before operating.
Robert, your 2015 Fleetwood Expedition 40X does indeed have glass windows, and yes, you can fix that separated kitchen vent window with the right adhesive. For your glass window that's detached from the crank mechanism's metal bar, Sikaflex 221 is the correct choice - it's specifically formulated for glass-to-metal bonding in RV applications and maintains flexibility for thermal expansion. The separation you're seeing is common on these frameless vent windows after 8-10 years due to UV exposure and temperature cycling breaking down the original adhesive bond.
The separation of your kitchen vent window from the crank mechanism occurs due to several factors specific to RV environments. UV radiation gradually breaks down adhesive bonds, particularly on windows that face south or west during extended camping periods. Temperature cycling is another major culprit - your Expedition experiences significant expansion and contraction as temperatures swing from hot days to cool nights, creating stress on the adhesive joint.
Road vibration compounds the problem, as the constant movement while traveling gradually works the bond loose over time. The original factory adhesive on 2015 models was often a basic structural adhesive that wasn't designed for the extreme conditions RVs face. Additionally, moisture infiltration around the window frame can weaken the bond from behind, especially if there are any small gaps in the exterior sealant.
Your observation about the window "flapping in the wind" indicates the separation has progressed significantly - this typically happens suddenly after the adhesive has been gradually weakening over months or years. The good news is that this is entirely repairable with proper materials and technique.
Before starting the repair, gather your materials: Sikaflex 221 adhesive sealant (one tube should be sufficient), isopropyl alcohol (91% or higher), clean lint-free cloths, a plastic putty knife or old credit card, and masking tape. You'll also need a caulk gun and possibly a heat gun or hair dryer for optimal curing conditions.
Clean both surfaces thoroughly - the glass window and the metal crank mechanism bar - with isopropyl alcohol to remove all traces of old adhesive, dirt, oils, and residue. This step is critical for proper adhesion. Scrape off any remaining old adhesive carefully with your plastic putty knife, being careful not to scratch the glass. Allow both surfaces to dry completely before proceeding.
Check the crank mechanism operation while the window is detached - this is a good time to lubricate the mechanism if needed. Also inspect the window for any chips or cracks that might have occurred during the separation. Choose a day with temperatures between 40-85°F and low humidity for best results, as Sikaflex 221 cures better in these conditions.
Apply masking tape around both surfaces to create clean lines and protect surrounding areas from excess adhesive. Cut the Sikaflex 221 tube tip at a 45-degree angle to create a bead width of about 1/4 inch - you want enough material for a strong bond but not so much that it squeezes out excessively.
Apply the Sikaflex 221 to the metal bar of the crank mechanism in a continuous bead, slightly overlapping at the end. The adhesive should cover the entire contact area where the glass will attach. Work quickly but carefully, as Sikaflex begins to skin over within 20-45 minutes depending on humidity and temperature conditions.
Position the glass window against the metal bar, pressing firmly and evenly across the entire contact area. Hold steady pressure for at least 2-3 minutes to ensure good initial adhesion. You should see a slight squeeze-out of adhesive around the edges - this indicates proper coverage. Remove excess squeeze-out immediately with a damp cloth or your putty knife before it begins to cure.
Support the window in its proper position using temporary bracing or clamps if necessary. The bond will be strong enough to handle light pressure within 2-4 hours, but allow 24-48 hours before operating the crank mechanism. Remove masking tape within 30 minutes of application while the surface is still tacky for the cleanest finish.
Consider professional help if you discover the crank mechanism itself is damaged or if the window glass has chips or cracks that occurred during the separation. A mobile RV service technician can assess whether the entire window assembly needs replacement, which involves removing interior trim and potentially exterior sealant work.
If you're uncomfortable working at height or if your kitchen window is particularly difficult to access safely, professional installation ensures proper technique and safety. Additionally, if you notice other windows starting to separate or if there are signs of water damage around the window frame, a comprehensive inspection by an RV technician can identify potential issues before they become major problems.
The repair should cost under $20 in materials if you do it yourself, versus $150-300 for professional service depending on your location and any additional work needed. However, if the window continues to separate after your repair or if you notice the crank mechanism binding, that indicates a more serious structural issue requiring professional diagnosis.
Help us improve this article by flagging technical issues or inaccuracies.
Was this guide helpful?
Try our free RV calculators and tools to help diagnose and plan your repairs.
Browse RV ToolsWeight calculator, electrical planner, propane estimator & more