Big Austin Healeys have always been notorious for heavy oil
consumption - even the manual says they may consume 1 pint of oil per
250 miles. While this was probably normal in the 1940s and 1950s it is
not the case on modern cars. Some of this oil goes past the valves and
mixes with the exhaust gases that are 'blown-by' the piston rings into
the crankcase. Our Healey is fitted as standard with a Positive
Crankcase Ventilation (PCV) system which links the crankcase to the
rocker cover and then via a T-piece across to the rear of one of the
carburettor air filter canisters. This is designed to reduce the gas
pressure built up in the crankcase and rocker cover, rather than reduce
the oil consumption.
The PCV system means that the oil fumes are sucked into the carburettors by the inlet manifold vacuum and burnt along with the fuel. When I accelerated hard in our Austin Healey 3000 I could see exhaust fumes in the rear view mirror, so it seemed the system was burning some oil as well as the crankcase fumes.
A coupe of years ago I decided to fit an oil catch tank in line with the PCV breather system to see if it would make any difference. I found a suitable one in polished aluminium with an inlet and outlet pipe and a small clear plastic tube showing oil level. The fumes and oil mist are drawn in, the oil and any un-burnt fuel condense out and the remaining gases are then sucked out into the back of the air cleaner and burnt as before. I fitted this using normal rubber tubing to/from the catch tank.
It did its job well as over the course of a year, covering about 6,000 miles, it accumulated about 1/2 pint of oil. This is released through a drain plug in the base of the tank which I then poured back into the engine for re-use. This meant that I had prevented the engine burning about 1/2 pint of oil a year, reducing both the emissions and the likelihood of the plugs becoming fouled by burnt oil.
This year I decided it was time to tidy up the engine compartment a bit and bought chrome finish air cleaners to replace the grey painted ones and thought it time to replace the rubber tubing. The engine has a chrome heater pipe running the full length so I bought some chrome plated, standard plumbing type, copper piping and using a plumbers pipe bending machine made up a pair of chrome pipes.
These now run along the engine, above the heater pipe, connected using short lengths of rubber tubing and jubilee clips and provide for a much tidier engine bay. The oil catch tank continues to operate as when first installed.
The fact that I have prevented at least 1/2 pint of oil a year being burnt by the engine makes fitting a catch tank well worthwhile, and using chrome plated copper piping makes for a much tidier engine bay than just using rubber tubing.
The PCV system means that the oil fumes are sucked into the carburettors by the inlet manifold vacuum and burnt along with the fuel. When I accelerated hard in our Austin Healey 3000 I could see exhaust fumes in the rear view mirror, so it seemed the system was burning some oil as well as the crankcase fumes.
A coupe of years ago I decided to fit an oil catch tank in line with the PCV breather system to see if it would make any difference. I found a suitable one in polished aluminium with an inlet and outlet pipe and a small clear plastic tube showing oil level. The fumes and oil mist are drawn in, the oil and any un-burnt fuel condense out and the remaining gases are then sucked out into the back of the air cleaner and burnt as before. I fitted this using normal rubber tubing to/from the catch tank.
It did its job well as over the course of a year, covering about 6,000 miles, it accumulated about 1/2 pint of oil. This is released through a drain plug in the base of the tank which I then poured back into the engine for re-use. This meant that I had prevented the engine burning about 1/2 pint of oil a year, reducing both the emissions and the likelihood of the plugs becoming fouled by burnt oil.
This year I decided it was time to tidy up the engine compartment a bit and bought chrome finish air cleaners to replace the grey painted ones and thought it time to replace the rubber tubing. The engine has a chrome heater pipe running the full length so I bought some chrome plated, standard plumbing type, copper piping and using a plumbers pipe bending machine made up a pair of chrome pipes.
These now run along the engine, above the heater pipe, connected using short lengths of rubber tubing and jubilee clips and provide for a much tidier engine bay. The oil catch tank continues to operate as when first installed.
The fact that I have prevented at least 1/2 pint of oil a year being burnt by the engine makes fitting a catch tank well worthwhile, and using chrome plated copper piping makes for a much tidier engine bay than just using rubber tubing.
Tony Merrygold of The Open Road
is an expert in classic car hire having been in business in the UK
since 1997 running The Open Road. Tony runs courses telling people how
to start up a car hire company, having trained over 200 people over the
past ten years.
Combining his 20 year background in sales and marketing with his knowledge of the classic car hire industry, in early 2008 Tony launched a new web portal Classic Car Hire World - listing classic and sports car hire companies around the world. Within three months of its launch this site acheived a Google PageRank of 4/10 and was showing on the first page of Google.com when users searched for 'classic car hire'.
Article Source:
http://EzineArticles.com/expert/Tony_Merrygold/117544
Combining his 20 year background in sales and marketing with his knowledge of the classic car hire industry, in early 2008 Tony launched a new web portal Classic Car Hire World - listing classic and sports car hire companies around the world. Within three months of its launch this site acheived a Google PageRank of 4/10 and was showing on the first page of Google.com when users searched for 'classic car hire'.
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