Bits and Pieces

7 May

Manchester XPAG Project – Progress May 2016

Some of you may remember that in 2013 we sponsored a group of students at the School of Mechanical, Aerospace and Civil Engineering, University of Manchester (MACE) to run tests on a XPAG engine to try to understand why classic cars had running problems with modern fuels. Unfortunately, time constraints and problems prevented the students from finding anything useful.

The good news is that after lengthy negotiations and with the help of MACE and Dave Haughton, we were able to access the facility and spend one week running the tests ourselves. All made possible by additional funding from the MGCC.

The first task was to improve the instrumentation that was fitted to the engine, this included installing thermocouples on the carburettors, fuel pump and cylinder head as well as vacuum gauges, etc. In all, 24 different parameters were measured for each of the 180 tests using a range of different fuels. A lot of data to be analysed.

Thanks must also go to the Anglo American Oil Company Ltd who supplied additional test fuels. With technical advice and a grant from the FBHVC we have identified the causes of the problems we all see with modern fuel. Furthermore, the tests have not only dismissed some of the myths, they have provided valuable information on ways we can mitigate the problems of running classic cars on modern fuel.

At the moment, I am testing one of the possible solutions on my 1949 MG TC to assess its effectiveness before writing an article.

One of the most demanding challenges faced by my car is the Ipswich to Felixstowe run organised by the Ipswich Transport Museum. This run is a victim of its own success with over 350 vehicles, 25 or more years old, and a great number of visitors travelling to Felixstowe, the 13.5 mile run is, in practice, a 13.5 mile stop-start traffic jam. Needless to say, there are numerous classic car casualties stopped at the side of the road, bonnets open to allow the engines to cool. Fortunately, this year the weather was kind. While it was a sunny day, cold winds from the sea kept ambient temperatures to around 13C, not a very challenging test for my car. Even so there were still a significant number of broken down classic cars at the roadside.

So how did my TC perform? Like many other T- Types, the sender for my temperature gauge is in the header tank for the radiator. With a thermostat fitted, the radiator temperature effectively gives an indication of excess heat generated by the engine. Going downhill when the engine is doing less work, the temperature drops, conversely it rises when going uphill. In practice, during normal running, this has proved a very useful means of determining how efficiently the engine is running on a given fuel, typically running around 72C on a super grade fuel and 75C on a standard 95 octane fuel. On the Ipswich to Felixstowe crawl, the temperature gauge barely reached 68C, normally running around the 65C mark. Considering our average speed was around 5mph, this is very low.

Does this mean the fixes have worked? Still more tests needed on hotter days. Watch out for the full report.

Paul Ireland

Right to the Core

I’ve noticed something interesting within Issue 33 of TTT 2, brass core plugs fitted to overcome the rusting experienced when fitting steel plugs.

Now that all sounds very good – as we know, brass will not rust but consider my article in Issue 24 of TTT 2 entitled ‘A Negative View’.

This article explained the phenomenon of electrolytic corrosion caused by dissimilar metals in contact with each other acting as electrodes of an electrical cell under the presence of moisture.

So on original manufacture we have steel core plugs in a cast iron block with no shortage of moisture from within the engine cooling galleries. Steel has a potential of -0.75V and cast iron a potential of -0.44V when acting as electrodes of an electrical cell in the presence of moisture.
With the more negative potential the steel will corrode in preference to the cast iron and this is clearly illustrated by core plug failures experienced by many owners of T-Types.

Now consider the fitment of brass core plugs. Brass has a potential of -0.30V and cast iron a potential of -0.44V when acting as electrodes of an electrical cell in the presence of moisture. The original design intent of the material interface has now been reversed as the cast iron block has the more negative potential.

Whilst the difference is well within the recommended maximum -0.25V, the cast iron will still be the material that will corrode in preference to the brass and that corrosion would affect the plug counterbore.

The internal cooling galleries of an engine will always be prone to corrosion and inhibitors present in anti-freeze reduce the tendency but why make changes that will compound the issue?

When the engine for TC0894 is rebuilt I will be opting for steel core plugs to be the sacrificial component of the engine assembly rather than the ageing and increasingly rare XPAG block.

Steve Cameron TC0894 (under full restoration)

Ed’s note: The use of brass core plugs has recently been discussed on the Triple-M forum. I noted that one contributor concluded that “the soft (little risk of damage to the block) brass core plugs, IF insulated from the iron block using a sealant, which you would do anyway (bath sealant) work fine, and will last far longer.”

TD12010 – Request for details of previous owners

John Gilks in New Zealand is looking for help in tracing previous owners of his car. John has owned TD12010 for 36 years and had details of previous owners as these were listed on the registration certificate. Unfortunately, the certificate was lost during a house move many years ago. He has subsequently tried without success to establish the names of previous owners.

John says that although he cannot be certain he is fairly sure that the car was exported to N.Z from new as very few pre-owned cars were imported to N.Z. in the 1950s. Under an arrangement with the previous owner back in 1982/84 he travelled to Wellington and picked up the car from a car park. From there he took it across Cook Straight by ferry and drove down the South Island to Dunedin where he lived. The car had recently been fully restored, probably late 1970s or early 1980s.The Transport Authority in New Zealand kept a very good history of vehicle ownership until the time when they transferred to a computer based system. Regrettably that history was eliminated on conversion to the replacement system. Ed: Where have we heard that before!

John’s e-mail address is johng(at)dbay.co.nz {please substitute @ for (at)}

TC7631 – Registration Mark JAD 513

Barry Robinson (Triple-M owner) has contacted me on behalf of Stephen Stewart Smith who owned this car when he was just 18 years of age, having spent the previous two years riding motorcycles ranging from a Triumph Tiger Cub to a BSA DBD 34 500 cc Gold Star.

Stephen, at 16. was employed by IMI Kynoch at Witton, Birmingham as an engineering apprentice. He used to see the TC being driven to and from work through the site and longed to own the car, never ever expecting that he would.

As part of his apprentice training he was regularly seconded to different departments on the site and one day ended up in a work area known as ‘Steam, Water and Gas’. He found himself working with a skilled fitter, who, by a stroke of luck, owned the TC. The fitter, Alan Radford, took young Stephen out for a ‘spin’ in the car with the hood down and he was hooked on the TC. When Alan said that he was going to sell the car, Stephen just had to buy it. At the time he had not even passed his driving test as he was learning to drive in his dad’s Sunbeam Rapier, so the car stayed on his parents’ drive until he passed the test.

Having passed his driving test, Stephen used to drive the TC to work and back on a daily basis and at every opportunity he would have the hood down with the tonneau cover fitted; he says it was just like riding a motorcycle!

As Stephen became a more experienced driver he wanted to go faster and found the TC to be quite a handful, especially keeping it in a straight line, which was becoming more and more difficult.

Stephen eventually sold the car (he can’t remember to whom, or for how much) and bought a Mini which his brother ‘souped up’, so much so that with wide wheels, SP tyres and a set of Koni’s it became a desirable target and was ‘nicked’.

The car is on the DVLA website so hopefully, the owner will see this and learn a little of the history of his or her TC.

Stephen can be contacted via Barry Robinson at bsjrobinson(at)tiscali.co.uk {substitute @ for (at)}.


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