Tech Tips: Summer 1990

Does the Light Go Off When the Door Closes?
Michael Thomason
Mobile, AL

As a small child, one of the great mysteries of life was whether or not the light stayed on in the refrigerator after you closed the door. This is a big issue for most kids. Unfortunately, I could never figure out how to tell for sure without getting inside and closing the door, and I wasn’t that interested.

Several decades later, I find myself possessed by a 1977 MGB roadster whose battery went absolutely flat after the car had not been run for several days. Bob Mason, friend and noted MGB expert (You’ve seen many of his articles printed in the Moss Motoring —Ed), told me that it was probably due to the trunk light staying on. He recommended removing the bulb to eliminate future problems. I was not sure he was right (a serious error) about the cause of my problem, and besides, I liked the light. As Yogi Berra is supposed to have once said, “It was deja vu all over again” as once again I was wondering how you tell if the light goes off when you close the door.

Well, it’s easier with an MG (or a Midget) than a 1946 Coldspot refrigerator. I removed one back-up light (2 screws) and low and behold, I could see inside the trunk. The light was on, as it turns out because the bracket holding the switch was bent. I straightened that out and could see the light go off when the trunk lid was closed. Once I was satisfied I’d gotten the switch in the right place I replaced the back-up light.

It’s too bad refrigerators don’t have Lucas back-up lights because if they did we wouldn’t have to grow up wondering if the light really does go out…. Fortunately MGBs do and so we can tell.


Reinstalling Seats After Carpeting
Lou Radcliffe
Long Beach. CA

After removing the seats and tracks from my 1979 MGB, in order to thoroughly clean and recarpet, much to my surprise, re-installing the seats and tracks was a real hassle. Here’s one solution: after unbolting and removing the seats, tracks and shims, take the two rear track bolts and bolt them back in place in the two rear holes, but from underneath the vehicle. The bolts protrude up through the pad, carpet, shims and track, making it much easier to properly place the seat tracks. Unfortunately for the front two holes, due to the lift bracket under the vehicle, you cannot bolt from underneath. Purchase two 4″- 5″ bolts from a hardware store, cut the heads off and hand bolt them into place from inside the vehicle. Once tracks and seats are in place, remove a bolt at a time, re-install proper bolts and fasten down.


Leaking Tank Sender Unit

(Applicable to post-1970 Sprite-Midget, Spitfire, TR7and post-1965 MGB.)

Cars that use seal (#293-110) and lock ring (#36T-665) to retain the tank sender unit in the gas tank can suffer from leaks in this area. This is particularly common when a new tank is fitted and the seal and lock ring are replaced as a matter of course. The most common reason for a leak here, is an incorrect sequence of assembly. (This often occurs when the parts books show the components in the wrong order.) The correct parts fitting sequence is as follows:

1. Place the lightly greased seal against the hole in the gas tank.

2. Insert sender unit into tank.

3. Place lock ring over top of unit and turn to lock.


The Kiss of Death to Frozen Parts
By Mike Bedney
Portland, OR

Not too long ago I had to remove the rotten wooden railings from my doors, and the car seat sliders from the wooden floorboards in my MGA. Not too surprisingly, nearly every one of the bolts snapped in half with the first crank. Then a mechanic friend of mine recommended a General Motors spray called “General Purpose Penetrant and Heat Valve Lubricant” (GM part #1052627) which retails for about $5. He made some claims about the ability of this stuff to loosen up the tightest nuts and bolls. He gave me a few shakes of what was left in his spray can, and low and behold – this stuff is a miracle! I sprayed a few frozen parts and left them overnight; and the next morning they came off just as nice as if they were greased on. I read the can (something I always save for last), and noticed it said “after just a few minutes” they could be taken off quite easily. I doubted it, but tried some other equally frozen nuts and bolts alter just three minutes, and it worked equally as well.

This is a must for every household, let alone if you’re a car restorer. It’s the kiss of death for all frozen parts!

(We haven’t tried this, and so can’t confirm its effectiveness, but thought we’d pass this information along and let you judge for yourself. —Ed.)


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