Classic Cars and Oil Leaks

Ahh, the infamous garage floor oil puddle.... Those of us with Classic Cars will be all too aware of this annoying problem.


Each time you take your classic American car out of the garage, there is a small puddle of fluid or multiple puddles of fluid in various different colours. Dark yellow or black for engine oil, red for transmission fluid and power steering fluid, then green or blue for coolant.

Although these leaks are annoying, most of the time they are not serious. When asking our Carrot Town Garage technicians for their opinion on the matter, they advise that a good rule of thumb is if you are finding a teaspoon size pool of oil under your car, then generally this is nothing to worry about. But if you are finding a larger pool then it's perhaps time to do something about it.


So why do these classic cars leak? The most common problem is the rear main engine seal or the front transmission seal. The rear main seal is on the engine; where the crank shaft comes out of the rear of the engine and connects to the flywheel. The seal's job is to stop the oil coming out from inside the engine. On more modern cars this is a one piece seal, however on older cars this is usually a two piece seal. The fact that the seal is in two parts obviously means that this is never going to seal as well as a 'one piece' seal. The early Ford Mustangs used a rope seal, which was literally two pieces of rope covered in grease. The later cars use a two piece rubber seal.


Corvettes have a similar setup, with one seal fitting into the sump and the other into the engine, thus encasing around the crankshaft. Replacement of the seals is usually straightforward, however on Mustangs it's necessary to undo the conrods and lower the crank slightly, to remove and replace the upper seal.



The other cause for leaks is the front Transmission seal on the gearbox. This goes around the transmission shaft and is to stop the transmission fluid leaking out onto the torque converter and your garage floor. Although these are a one piece seal, they generally fail due to age or general wear and tear. Transmission fluid which is usually red, has a much lower viscosity compared to engine oil so is more prone to leaking. Replacement is fairly straightforward and just requires the removal of the transmission from the car. The seals are not expensive for these jobs and are worth doing if you are getting more than a teaspoon on your garage floor or constantly having to top up your fluids.

If you need to book your Classic Car in for a service, or if your car is in need of repair and restoration, just call our team on 01354 552427 to get your car booked into Carrot Town Garage in March. Remember, we can pick up and drop off your car for you too if it's not running.

"You're Never Late in a V8!"



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