The Garage – Precious Bodily Fluids by Mike Owen of Owen Automotive

General Jack D Ripper in the movie, Dr Strangelove or: How I Learned to Stop Worrying and Love the Bomb, was obsessed with protecting our “precious bodily fluids”.   Likewise, we have reason to be careful about fluids and their levels in our cars.

Engine – Our LBCs require higher viscosity 20W 50 oil.  Do not use light oil like 5W 20 available inexpensively from department stores.  Oil level should be checked monthly during the driving season.  To change the oil, warm the engine first and drain.  Allow it to drain overnight to get the last half a cup.  Change the oil every year unless the car has driven less than, say, 500 miles since the last oil change.  On early MGBs, it may be necessary to unbolt the oil cooler to drain the oil.  B engines tend to leak.  The culprits can be leaks at the valve or tappet covers.  Others include a leaking oil pressure gauge hose or oil cooler hose.  Be sure to add ZDDP.  Add 8 ounces of Lucas Engine Break-in Vehicle Additive with each oil change.

Gearbox – While you can use 20W 50 engine oil, a preferred lubricant would be a gear oil like

Red Line MT90 High Performance Lubricant.  Replace it less often, say every 5 years.  Do check the level annually and top up to “max”.

Differential/Rear axle – Leave the differential check alone unless it shows signs of leaking.  Use Lucas Heavy Duty 85W 140 Gear Oil.  Pennzoil Hypoy C 80W 90 Gear Oil is acceptable but nothing special.  Check the breather cap to ensure it is clear of gunk so the axle can breathe.

Carburettor dampers – Use 20W 50 engine oil.  Fill to 1 inch down from the top of the chamber so that the piston tube top is just covered.  Check regularly. As an experiment, try a lighter oil – 10W – to see if acceleration improves.  Use a Q-Tip to remove excess amounts of oil.  Note that some cars need damper caps with a vent hole.  Ensure the caps are the correct type for the vehicle.    

Master cylinder – Using an eyedropper, fill the MC with brake fluid flush with the bottom of filler neck.  There are differing opinions concerning whether to use glycol based (DOT 3/4) or silicone (DOT 5) fluid.    DOT 3/4 fluid will absorb water and must be changed every two years or so.  It also will destroy paint if it spills or leaks.  DOT 5 will not absorb water and it rarely needs to be changed.  Check regularly and do not mix the different DOT fluids. Expect some loss due to brake shoe wear and – on MGBs – brake cylinder seals sometimes weep in the winter cold. 

Front and rear dampers – Bounce the car to check if the dampers are working.  If the level is down, fill with 10W hydraulic damper oil such as Moss Shock Fluid.  While filling, bounce the car and work the lever arms to remove any trapped air in the dampers.  If the external dampers are dry, there is usually no need to touch them.  If they appear to be leaking, they will usually leak if refilled.  A rebuild may be in order.

Cooling system – Use a 50/50 mix of antifreeze and water year round.  Fill to a point about 1 inch down the filler neck or the radiator top.  Be careful not to overfill as the excess will boil off until the system reaches a happy level.  The system should be flushed every three to five years.  Drain the coolant from the radiator cock and recycle the fluid.  The one on the engine block is usually blocked and useless.  Flush with fresh water from a hose through the filler neck and allow to drain.  To flush the heater, remove the hose at heater control valve and gently pour in 2-3 litres of fresh water from a cup.  Later MGBs do not have a drain cock on the radiator.  If the radiator is out of the car for servicing, arrange for a cock to be installed.  Otherwise, it is a messy job to remove the lower hose and flush.  Slacken the hose clamp and wiggle a screwdriver between the hose and pipe.  Allow the coolant to drain slowly from the system.  Evans Waterless Engine Coolant is an impressive product to use instead of normal coolants.  It is expensive but does not corrode and never has to be replaced.  It is ideal for cars with aluminum cylinder heads. 

Fuel system – Always use a high octane fuel such as Chevron 94 octane fuel.  For the winter layup, add a fuel stabilizer.  Also, add ½ cup of methyl hydrate to fuel to remove water accumulation in the fuel – provided that the stabilizer doesn’t perform this task.  For storage for an extended period, drain all fuel from carburettors. 

Steering rack – Use Pennzoil 80W 90 Gearplus oil – not grease.  The easiest way to top up the steering rack is through the rack damper cap.  Another way is to jack up one side of the car and add oil through a gaiter boot.  Top up with about 1 ounce of oil.  MGBs are prone to have water enter the system.

Front suspension – Lubricate the front suspension with a black moly grease annually.  Fill at the nipples until grease bleeds from seals.  The rubber link and swivel pin seals will perish over time and if cracked or torn should be replaced. 

Handbrake – Use an 80W 90 oil – not grease which will bind the handbrake cable.  Keep adding oil until it runs out of both ends of the cable. 

Propeller shaft – Use a black moly grease to lubricate the universal joints.  As the U-joints are difficult to reach with a standard grease gun fitting, get a needle point for this job.  See JB Precision for the part.

Wire wheel hubs – Use a red wheel grease thickly applied to ensure hubs are well greased to prevent corrosion or locking.  Do this as part of the annual brake maintenance.   

Battery – Forget everything in manuals about topping up battery cells.  Batteries are all sealed today and there are no fluids involved except to use a mixture water and baking soda to clean the terminals.  Add some Vaseline to the terminals to prevent corrosion – especially the positive terminal which corrodes quickly.    

So, there you have it.  Everything you wanted to know about precious bodily fluids for our cars…