Rain Gutter Rust - Need Advice

It rained really hard here last night and the passenger floor got wet in my '99 XJ. I took a close look and noticed that the rain gutter at the front corner has rust bubbles. I have experience doing some rust removal, but is this job better handled by a body shop?

You indicate rust bubbles only, but you don't mention if there is actual hole. I suspect your leak may be where the fan blower motor pokes through your firewall, as this is the area prone to leaking.

First, pull your passenger side front carpet back far enough to where your expose the firewall. You don't even have to remove your front seat to do this. Now take a hose and spray your windshield area really well for a little bit, but do not let water hit where you suspect the leak. Then check the firewall area inside the cab, and I'll bet you'll see a trickle of water running down the firewall at the base of fan blower.

What happens over time is that the foam seal for the fan blower motor / firewall rots away, and lets water in from the engine bay.

The fix is to simply add some sealant where the fan blower pokes throught the firewall, in the engine bay. Seal the foam area really weel. You may have to move some piece of emmissions equipment, but it's only a few bolts and moves aside so you can reach this area.

Also, check to see if you have a wire loom hanging right above the blower area. That's where my water was coming in on my '98, as it was dripping from there straight into the blower hole....

I should have been more specific... the water was collected on my rubber floor mat and they are shaped in such a way that water coming in the firewall wouldn't get on them, but rather go under.

DaveD912 said:

It rained really hard here last night and the passenger floor got wet in my '99 XJ. I took a close look and noticed that the rain gutter at the front corner has rust bubbles. I have experience doing some rust removal, but is this job better handled by a body shop?

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The rain gutter on the roof?

Yes, right where the rain gutter ends at the top corner of the windshield. I looked along the drivers side rain gutter and that has paint bubbles all along it also. I've got zero rust besides what I'm finding in the rain gutter - it's very odd unless this is a know problem. I need the rain gutter to be strong - that's how'd I mount a roof rack if I ever decide to use one.

DaveD912 said:

Yes, right where the rain gutter ends at the top corner of the windshield. I looked along the drivers side rain gutter and that has paint bubbles all along it also. I've got zero rust besides what I'm finding in the rain gutter - it's very odd unless this is a know problem. I need the rain gutter to be strong - that's how'd I mount a roof rack if I ever decide to use one.

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It's a common problem. Even my otherwise rust-free 99 has a little spot of surface rust there, and my 95 has nasty leaking holes. If it's just surface rust so far, treat it carefully and make sure it's well protected. It won't weaken the rain gutter enough to worry about, but it's hard to patch if it rots through.

I suspect that on my 95 some of the rust came from beneath because the windshield also leaked for a long time. You should check carefully for leaks around the top of the windshield. Sometimes the bond of the urethane to the metal fails, and rust builds up there. It can leak and get the headliner wet, and I am guessing that the dampness up there also speeds up the rotting out of the roof.

You should also check the mountings for your roof rack. Sometimes the well nuts leak.