MG Manawatu

After a recent drive in my ‘B I noticed a puddle of fuel under the car at the back of the fuel tank. After some investigation it turned out to be one of the two rubber fuel hoses that connect the pump to the fuel feed pipe under the car had perished and gone mushy around the clamp and had started to leak.

These hoses are well hidden from everyday view and easily forgotten about, so I decided it was timely to replace all the fuel hoses. Interestingly the under bonnet hoses were still in good condition unlike their under car counterparts.

Just a reminder to everyone to check these hoses periodically and particularly if you have a late B with the HIF4 carb set up, the fuel hose that connects the two carbs behind the air cleaners. Well hidden and sits above the hot exhaust manifold……one of our group has had this hose let go whilst on a previous run.

Tags: Technical by Dom
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MGB Oil Consumption.

An often overlooked reason for excessive oil consumption is the restriction or blockage of the engines crankcase breather system. With the “breathing” ability of the engine impaired it will expel oil from wherever it can – passed seals or forcing past the piston rings. As one of our group recently experienced after freshly rebuilding his engine it continued to use excessive amounts of oil. Cleaning out the engine breather provided an immediate fix much to his relief!

The MG Owners Club in the UK has some useful information about this (PDF File) - MGB Crankcase Breather (MGOC) – whilst they go to the extremes of opening the breather and replacing the gauze, I have found that removing the breather and leaving it to soak for a good length of time in a strip bath (such as an engine reconditioner would have) is quite effective in unblocking this. It should also be remembered that the later MGB oil filler cap has a breather in it and this should be replaced every 12,000 miles for the same reasons.

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A little something all of us should now be aware of is the gradual shift away from the conventional lead acid car batteries we are all used to, to the new calcium type batteries that are now prevalent in the market place. Calcium batteries are still lead acid but have calcium incorporated into the plates.

All the major new car manufacturers over recent years  now specify and manufacture their cars with calcium type batteries as factory standard. As the number of vehicles with these batteries has increased, the battery suppliers have been phasing out the old lead acid type and superceding these to the new calcium type batteries. Chances are if you have bought a new battery in the last couple of years it may well be a calcium type battery.

So what does this mean for us using older cars? Not a lot really – the new batteries are more efficient with better CCA (Cold Cranking Amps) ratings, casing sizes and terminal positions have altered in some cases, so fitment may require some adjustment. The biggest thing we need to be aware of in vehicles that are infrequently used is the problems with charging the battery particularly if it has become heavily discharged (flat!). A conventional battery charger will not fully charge a calcium battery. 

A 4-stage charge is used, specially designed for calcium batteries. Stage one (bulk or constant charge) quickly charges the battery while stage two, the absorption mode (constant voltage), ensures the battery is thoroughly charged. A third stage is the critical stage for calcium type batteries. It charges the battery to 16 Volts to remove any acid stratification and returns a full hydrometer reading. The final stage in the charging process (float), maintains the battery at a safe voltage ready for use.

Most garages and dealerships all now have specific calcium chargers and you can buy from auto accessory specialists calcium chargers for the home but the better ones of these are still relatively pricey.

My understanding is that a standard battery charger or permanent automatic trickle charger will maintain a calcium battery if it is not discharged. So if your battery has gone flat and it’s not that old and won’t appear to charge – you may have a calcium type battery that requires a calcium charger.

If anyone has further knowledge of this let me know and I will add it to this post.

Tags: Technical by Dom
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With so many of us owning and driving MGB’s I thought this was well worth everyone reading:

In the November 2008 issue of “Safety Fast” is an interesting note about the boot lock on MGB’s – particularly on the roadster. Basically they tell the story of some people touring in their MGB and when they arrive at their destination cannot open the boot no matter how they try, to get to their luggage. In the end the key lock was cut off with an angle grinder which also damaged the boot lid resulting in a hefty repair bill afterwards.

It transpired that the bolt on the underside of the boot lock (see picture) had worked loose allowing the catch plate to move causing it to no longer make contact with the unlock mechanism. With this bolt missing there is simply no way that the boot can be opened.

After reading this article I decided it would be a good idea to check this bolt on my MGB’s – the GT was nice and tight but the one on my roadster was just finger tight!  So very pleased I did this quick check. The warning therefore is to make sure this tiny, insignificant bolt is tight: You have been warned!

Tags: Technical by Dom
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