Bob’s Garage – Spring 1987

More tips! This is the technical tip issue for Bob’sGarage. I have a number of tips, some based on comments and suggestions, and others which were sent in by customers. They all have one thing in common. We haven’t had room for them in previous Moss Motorings, so I thought I’d lump them together in this issue. We always like tips which are based on people’s experience trying to keep things going. If you have an idea, but have been a little hesitant to send it in, don’t be shy, we won’t laugh at you.


MGB gearboxes (especially the early ones) aren’t the most bullet proof of modern day designs. However, this doesn’t mean they can’t give reliable service over extended periods. As with any mechanical component, proper lubrication is critical.

A favorite topic of conversation among B owners is what sort of oil to put in these funny English gearboxes, and this is where the trouble starts. Everyone has a pet theory, even the factory books have been known to provide conflicting information. Whatever one might think, engine oil seems to work best, not 90wi. gear oil.

Unfortunately, many people, upon hearing that the gearbox uses engine oil, mistakenly assume this means oil is fed to the gearbox from the engine. Not so. The gearbox has its own oil supply which leaks out on the driveway in the same manner as the engine’s oil supply. A lot of “slow” MGB gearboxes are simply suffering from lack of oil. This condition must not be left unchecked.

If you own an MGB and have never checked the gearbox oil level, now’s the time to start. First off, let’s bear in mind the simple fact of personalities. MGBs (in fact most British sports cars) require that you occasionally get down on your knees and grovel before them. Think of it as idol worship. Bearing this in mind, wander over to the passenger side of the car, open the door, get down on your knees, and crawl head first into the passenger’s footwell.

Once in position, knees on the ground, head where your feel belong, look for someplace really inaccessible. Let’s try under the carpet, between the firewall and console on the transmission tunnel. Peel back the carpet to expose a rubber plug (or empty hole as the case might be.) Lurking somewhere down there, half covered by old grease and dirt, is a combination filler plug and dipslick. Pull this out. wipe it off, then attempt to restore it to its original location in the gearbox. Once done, pull it back out and get a proper reading of the oil level.You may find the hole in the trans tunnel is conveniently designed to be a little too small for you to get your hand down in there. Use the stiff upper lip method…perseverance.

If the level is at the top mark, all is well. If not, the best way to add oil is by using some cheap plastic tubing from the hardware store and a funnel. Feed the tubing into the tiny little hole in the transmission, then slowly pour oil through the funnel. Remember, the gearbox doesn’t hold all that much oil. so check the level often. You don’t want to over fill it. Put everything back together, crawl out, and know in your heart of hearts that the MG gods have been satisfied.

We have heard quite a few stories about cars that worked well until the day the gearbox ran dry and locked up at 55 mph. Make a gearbox oil level check part of your routine maintenance schedule and you’ll never have trouble again. Well, at least not until some thing else goes wrong.


Some of our customers have commented that our upholstery adhesive (#221-560) comes with a stack of warnings about the nature of its contents, but no instructions. We therefore offer the following advice for all types of upholstery adhesive…

Apply a thin coat to both surfaces. A common shortcut is to apply a thick coat to one surface only. This will not work! Contact adhesive is cohesive, it is designed to stick to itself. Wet upholstery adhesive will stick to a surface, but will not bond two surfaces together.

Allow time for the adhesive to dry until barely tacky. The ultimate strength of the bond depends on the adhesive having a chance to gas off. Remember, although almost dry upholstery adhesive doesn’t feel sticky to your finger like an adhesive might, it will stick to itself.

As many of us can attest, it’s frustrating to end up with a gather where it doesn’t belong, or the whole piece too far left, leaving a big gap at one end. To insure the piece is aligned correctly, apply the adhesive to a small strip or patch in the middle of the piece, let it set, then put it in place. Now you can move it slightly, or even pull it back up without causing damage. When you have it aligned right, glue the remainder of the piece, working out from the original contact spot.

Here are two more little tricks to help the job go smoothly. Contact adhesive dries faster on porous surfaces, so apply it to a metal surface first, then on the fabric. Also, when gluing foam, don’t use too much adhesive; otherwise, the foam will be saturated and when you press on it, the foam will collapse leaving visible dents in the finished panel.

Always use upholstery adhesive in a well ventilated area, the fumes will make you light-headed or even physically ill. You now know as much about upholstery adhesive as the pros. One last note though. Never use upholstery adhesive to glue your neighbor’s children to the sidewalk. They’ll be hard to remove.

MGA RADIATOR by Bernard Allison

This idea may be nauseating to some of the dyed in the wool British car owners, but the best modification I had done on my 1957 MGA was to have the radiator filler neck changed at a radiator repair shop.

There are two sealing rings in a radiator neck. The distance between the British seals is 1″, and the American distance is 3/4″. By changing to the 3/4″ size, I am now able to use the siphon-style radiator cap and overflow bottle. Now when the coolant expands it raises the cap, flows to the bottle and returns back to the tad when cool, without loss of coolant.

Also, the radiator can be pressure tested with a regular tester.

Bernard will receive a Moss gift certificate for his contribution.

MGA Coolant Overflow by Lyn Biglin

I purchased a new MGA 1600 m 1961. Over the years, I have encountered problems of coolant loss in hot weather. I purchased after market surge tanks, but they did not fit too well in the engine area. At the local wrecking yard I found a late model General Motors factory plastic surge tank. It is approximately 6″ long x 4″ wide x 4″ high. I mounted it under the top of the right front fender near the voltage regulator on top of the firewall shelf. Very good fit. I used a wire tie to fasten the overflow tube to the brake line. I ran a continuous 3/8″ copper tube from the supply tube, around the valve cover, following the heater supply copper tube to the overflow tube on the radiator. Clamp the overflow lube to the heater tube. Bend the new copper tube 45° and slip fuel line on the radiator overflow tube and connect to your new copper overflow tube. (Cut radiator tube with a hack saw.) Use fuel line as it will not crimp. Plastic tubing will crimp and restrict water flow.

This works very well and saves coolant.

Lyn will receive a Moss gift certificate for her contribution.

(We often receive similar tips form different people. The two preceding tips deal with a subject common to all types, not just MGAs-Ed)


We recently saw an article by Gary McGovern of the Southeastern MGT Register in their newsletter “MG Talk”. In the article. Mr. McGovern writes about an oil pressure problem he experienced with the Moss #435-380 replaceable element oil filter conversion for the MG TC and early TD. Although he solved his problem, be never knew why his solution worked.

The element for this conversion (#435-390) is marked lop on one end. In fact, the element can go either end up as long as the metal screen is at the top of the element when it is placed in the canister. This screen keeps the gauze from being sucked into the outlet, and subsequently blocking the flow of oil to the engine. For years, a lot of people have been installing these filters with no regard to which end goes up. Although there may be no problem in this, it’s a good idea to make sure the metal screen covers the outlet.

Window channel strip installation can take hours of frustration, or just minutes if you know this trick. First, clean off the old black fuzzy strip using a glue solvent if you have one. Find a piece of wood slightly thinner than the channel slot, masking tape and black or clear silicone glue. Don’t use glue that sticks firmly on contact. Use a flexible pine wood strip if the channel is curved. A one quarter- inch thick yard stick works great on an E-Type Jag, for example. Next, cut a measured length of fuzzy strip off the roll and fold it over the edge of the stick. Check to see if the slick with the strip folded over it will fit nicely into the channel. If it does, then lay the stick flat on a table and lay half the width of the strip along the top of it. Using masking tape, attach this side to the stick by catching only one sixteenth of an inch of the strip along its edge. Turn the stick over and fold the strip over the stick’s long edge, attaching the other side along the edge of the strip. Apply the silicone glue to all three exposed sides of the folded strip and carefully position the glued strip and stick combination to the window channel. Push it in and while holding it in place, slowly peel back the masking tape out of the channel. If you have only caught the edge of the fuzzy strip, this should be easy lo do. Slide the stick up and out, leaving the strip to dry overnight. Presto! A perfect installation with no mess and fuss.

Richard will receive a Moss gift certificate for his contribution.


I recently bought an MGB in above average condition. The father of the girl who owned the car did the selling (what little was needed). In the discussions he mentioned that they had recently put a new battery in the car because the old one wouldn’t hold a charge. He also indicated that the replacement battery was a bit old, so initially I didn’t think too much about any electrical problems.

The car ran fine with no problems for a while, then suddenly the starter began turning the engine slowly, and if I didn’t drive the car every day (heresy) I really worried whether it would start the next day. Eventually it wouldn’t.

With the help of a friend, we began disconnecting one thing at a time with a meter hooked to the battery. We finally discovered the thermostatic fan switch was shorting out when it was in the “off” position. The switch worked in that the fans ran and shut off presumably correctly. The problem showed up after I had topped off the radiator. Apparently, when the radiator was low there was no problem because the switch is mounted in rubber and there was no coolant to conduct through. When I filled the radiator it submerged the bulb in coolant. In the “off” position, the fan switch shorted through the coolant to the radiator, causing the battery to drain.

Herb will receive a Moss gift certificate for his contribution


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