VSCCA MG Oil Leaks

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Article: MGTC OIL LEAKS SOME SUGGESTIONS TO IMPROVE THE SITUATION. October 2009 a new lady joinedour house "a pretty 1948 MGTC". I immediately began the process of getting to know her.One thing that the MG's do well when parked is leak a little oil. From my observations of ours & other TC's there are some common leak points, being: > Engine: > Rear main > Front main > Side cover > Oil pressure line outlet to head > Oil pressure line to oil filter ( in my case we have a late TD pump & > filter assembly fitted, no obvious leaks here) > Tappet cover. > Sump plug washer > Gearbox: > Drain plug washer > Breather plug washer. > Rear main. > Differential, however my car is quite tight here, no leaks. > Shock absorbers. The engine front & rear mains require a little bit of work & there are some well documented solutions, my car isn't too bad, so I didn't need to explore this any further.The side & top tappet covers tend to leak a little, mine does but not excessively, you can persevere with the cork gasket using aviation compound & you can use a silastic adhesive. There are also nitrile rubber or viton seal sets available. Oil pressure lines, this is where I have had the most success. The original copper washers were well past their service life, copper washers for oil pressure lines should never be re-used. I found replacements provided by the MG parts suppliers to be unsuitable. So I turned to the hydraulics industry & obtained Dowty washers. Dowty washers (see photo) I believe are a British invention consisting of a steel washer with a nitrile rubber or viton seal vulcanized to the inner diameter, the seals are capable of withstanding high temperatures & pressures, far greater than what the MGTC can subject them to. Dowty washer are sized by their internal diameter or the connection thread major diameter, though larger ID seals can be used where large chamfers are found. After use all leaks dried up & my engine oil pressure actually increased. Another issue concerns the engine side cover breather pipe, if yours is touching the oil pressure fitting that feeds the head & pressure gauge then it is likely you will get leak from that fitting, I have seen this on a number of cars & it caused by the pipe being fitted upside down.> Engine sump plug washer, gearbox drain & breather plug washer leaks were also eliminated using the dowty washers.Caution, the Dowty is designed to seal against two parallel surfaces, if you have a large chamfer then the Dowty may not seal. Other solutions can be explored such as a a larger ID Dowty (take care to centralize) or an o-ring & steel washer combination, I suggest you consult a hydraulic component supplier such as Pirtek if you have any concerns. The differential, as I said my car is quite tight, however some cars develop leaks at the pinion shaft, Moss (Europe/USA) manufacture seal flange kits that remedy this. Shock absorbers, apart from a stop gap solution such as oil seal conditioners (rubber swelling agents) the only course is to rebuild each unit. I have located a company in Mittagong who can fully rebuild the TC units for around $150.00 each, I am advised this is quite reasonable. > > Gearbox rear, I am yet tackle this. One other point of note are oils. Everyone including my cars previous owner seems to have their own angle on the required oil type & viscosity. I say when in doubt refer to the manual. However some oils no longer exist & Australian conditions can demand a higher viscosity, this is when you need the advice of an expert. I have found the Penrite range to be excellent & their website is very good, offering recommendations along with data sheets. The oils recommended for the TC were spot on. If anyone has any queries please feel free to contact me. Craig Robinson Craig can be contacted through the Web Master on sales@forestrealestate.net.au


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