Spanner Works: Donnie Tarentaal

A regular feature outlining the activities of FMM’s workshop personnel who are responsible for repairing, renovating, refurbishing and restoring the museum’s large and varied collection of vehicles. This month we report on Donnie Tarentaal giving the museum’s immaculate MG TF a new lease of life… 

In October 1953, the MG TF was launched as the final model in the company’s T-series, before being replaced by the sleek, entirely new, MG A in 1956. The TF was received with mixed emotions. It used the same XPAG 1 250 cc engine from the TD, but with an increased compression of 8,1:1, larger valves, stronger valve springs and larger SU carburettors. While some MG purists found the lower, sloping radiator grille and faired-in headlamps controversial, the general automotive market at the time still considered it outdated versus its rivals. But in time, the more flowing appearance grew on the MG faithful and today it is definitely considered an appreciating asset, especially considering less than 10 000 production cars left Abingdon between 1953 and 1955.

FMM’s example is from 1954 and in recent years has undergone a nut-and-bolt cosmetic restoration, while the engine and gearbox was kept in its beautiful original condition. But with time, some mechanical gremlins reared their ugly heads and needed to be addressed. Donnie Tarentaal explains the process.

“The first problem encountered was a tendency for the gearbox to get stuck in third gear. At first, it was sufficient to remove the top cover, clean the selector forks and re-lubricate the detent spring and ball assemblies. However, it wasn’t long before it was stuck in third gear again, which made it clear that the selector and gear assemblies were worn and needed to be refurbished. When the top cover was opened again, it was found that the selector forks were badly worn and that there was some ingress of moisture. It was then decided that the gearbox would have to be removed, stripped, cleaned and rebuilt.”

So Donnie set about his task and once the gearbox was out and on top of the bench, a much clearer understanding was gained as to what needed to be done. Firstly, every component was cleaned thoroughly and any surface rust removed. Then, the worn selector forks were welded up and reground in the areas where excessive wear was present. The main gear assembly was also removed, cleaned and the gears were deburred.

When the time came to reassemble the gearbox, Donnie started the job under the experienced eye of workshop manager Lorenzo. The utmost care was taken to remove any excessive play in the gear assembly and that the running pattern would be as close to the middle of the gear as possible. Fresh detent springs were also inserted to ensure a smooth, positive gear selection. With the gearbox refitted to the car, Donnie started the car and the gears shifted smoothly and easily. Great, job done! Or so he thought…

Donnie noticed a rough engine idle and so checked the oil and water. Sure enough, there was a mixture of the two substances and that is never good news for any motor. This meant the cylinder head would have to be removed for repair and to replace the gasket. With the car in such a beautiful condition, it was decided to carefully remove the engine to be able to work on it on the bench instead of in the car.

With the engine out, a complete strip-down ensued. With the water and oil mixing and running through the entire engine, a thorough clean was required to prevent any contamination of the oil and water channels in the future. The cylinder bores were honed, the pistons were cleaned of years of carbon deposits, and the cylinder head was sent for refurbishment and to have a new gasket made up.

After acquiring a few new parts and cleaning all the reusable parts, the time had come to reassemble the engine. Again, Lorenzo was at hand to offer advice and assistance during the process. After each piston assembly was fitted, the engine was ‘turned over’ to ensure it moved freely each time. The new gasket and refurbished cylinder head were fitted and torqued to specification and the engine timing and valve clearances were also set.

With the engine fully assembled, it was time to reinstall it to the vehicle. This is always a team effort, especially with older cars and their narrow engine bays. Once installed, the overhauled SU carburettors were fitted and the time had come to start up the TF. Everything went smoothly, and after running checks in the workshop and final tuning of the carburettors, Donnie took Wenstley along for the first run. Needless to say, they returned with big smiles!