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Tips
Tips

It leaks when it rains!

Alex H.

Freshman Member
Offline
My 73 MGB has a leak that shows up on the floor mat on the drivers side. It doesn't take much moisture to get a puddle on the mat. I tought it might be leaking related to the air vent intake plenum or grill. How does one get the chrome grill off?
 
Of course it leaks . . . It's an MG, isn't it?

I had this same problem. There are couple of likely suspect spots where water can come in.

-- The fresh air box. That's the place under the vent grill you're talking about. Is the drain tube blocked? There's a hole in the bottom of the box that SHOULD have a rubber tube attached to it to drain it. (It's on the RH side.) Original tubes have a bulb-and-slit at the bottom (weird design) -- often they get blocked up with gunk, which means water backs up in the fresh air box and into your footwells through the vent doors. You can try pushing a stiff piece of wire or coat hanger through the drain hole to see if you can unclog it, or reach the "bulb" at the bottom from underneath.

You also may just have a big accumulation of leaves and other junk in the bottom of the fresh air box, clogging the drain.

You SHOULD be able to gently pry that chrome grill piece up and off. Just take care you don't scratch your paint with your prying device. Originally, the grill was held to the hood holes with "blind fixes," and once you pull the grill out, they're useless. But nevermind them, you don't really need it fixed permanently in place, now do you? Mine just sits in there "loose," no problems. (Makes it easy to pull when waxing the hood.) Some people use small blobs of silicone sealant to hold it down. Also, it's a very fine idea to put a piece of screen or mesh underneath the grill before you put it back. Keeps leaves and other crap from accumulating in the bottom of the fresh air box. Moss sells precut ones, or you can make one yourself, easily enough, using hardware cloth or screen.

-- The windshield washer jets are another likely subject. Often the rubber gaskets get dried out, allowing water to come in. Check those out. Careful application of small amounts of silicone sealer might help, if you're not up to replacing the rubber gaskets.

-- In my case, I was getting water in around the rubber-to-glass seal in the windshield. I used flowable silicone to seal this up better. (Just stuck the nozzle of the silicone tube behind the rubber and squeezed some in.) I especially had a problem on the outside corners of the dash.

One thing you MUST do is make sure you get your footwells thoroughly dried out. It doesn't take much moisture to start those floorboards rusting. Remove the seats if you can to check and make sure you didn't get water under there, to.
 
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