OIL LEVEL CHECK
See Figures 1, 2 and 3
Every time you stop for fuel, check the engine oil making sure the engine has fully warmed and the vehicle is parked on a level surface. Because it takes a few minutes for all the oil to drain back to the oil pan, you should wait a few minutes before checking your oil. If you are doing this at a fuel stop, first fill the fuel tank, then open the hood and check the oil, but don't get so carried away as to forget to pay for the fuel. Most station attendants won't believe that you forgot.
- Make sure the car is parked on level ground.
- When checking the oil level it is best for the engine to be a normal operating temperature, although checking the oil immediately after stopping will lead to a false reading. Wait a few minutes after turning off the engine to allow the oil to drain back into the crankcase.
- Open the hood and locate the dipstick which will be in a guide tube mounted in the upper engine block just below the cylinder head mating surface. The dipstick may be located on the right or left side of the vehicle depending upon your particular engine. Pull the dipstick from its tube, wipe it clean and then reinsert it.
- Pull the dipstick out again and, holding it horizontally, read the oil level. The oil should be between the FULL and ADD marks on the dipstick. If the oil is below the ADD mark, add oil of the proper viscosity through the capped opening in the top of the cylinder head cover (or oil fill tube on most Oldsmobile engines). See the oil and fuel recommendations listed earlier in this section for the proper viscosity and rating of oil to use.
- Replace the dipstick and check the oil level again after adding any oil. Approximately one quart of oil will raise the level from the ADD mark to the FULL mark. Be sure not to overfill the crankcase and waste the oil. Excess oil will generally be consumed at an accelerated rate.
OIL AND FILTER CHANGE
See Figures 4, 5, 6, 7, 8 and 9
If the vehicle is operated on a daily or semi-daily basis and most trips are for several miles (allowing the engine to properly warm-up), the oil should be changed every four months or 6,000 miles on all 1964-74 models. On 1975-78 models, the interval is six months or 7,500 miles. 1979 and later models increased the time interval to 12 months while keeping the mileage (7,500) the same (Diesel interval is 5,000 miles). Make sure that you change the oil based on whichever interval comes first.
If however, the vehicle is used to tow a trailer, is made to idle for extended periods of time such as in heavy daily traffic or if used as a service vehicle (police, taxi, delivery) or the vehicle is used for only short trips in below freezing temperature, the oil change interval should be shortened. Likewise, if your vehicle is used under dusty, polluted or off-road conditions, the oil should be changed more frequently. Under these circumstances oil has a greater chance of building up sludge and contaminants which could damage your engine. If your vehicle use fits into these circumstance, as most do, it is suggested that the oil and filter be changed every 3,000 miles or 3 months, whichever comes first.
The oil drain plug is located on the bottom of the oil pan (bottom of the engine, underneath the car). The oil filter is located on the right side of the inline 6-cylinder engine and on the left side of most other engines. Although most vehicles covered in this guide utilize a spin-on oil filter, some 1968 and earlier vehicles were originally equipped with a canister and cartridge type filter. On these earlier vehicles, the canister must be removed in order to access the cartridge.
Always drain the engine oil after the engine has been running long enough to bring it up to normal operating temperature. Hot oil will flow easier and more contaminants will be removed along with the oil than if it were drained cold. To change the oil and filter:
- Run the engine until it reaches normal operating temperature.
- Raise the front of the vehicle and support it safely using a suitable pair of jackstands.
- Slide a drain pan of a least 6 quarts capacity under the oil pan. Wipe the drain plug and surrounding area clean using an old rag.
- Loosen the drain plug using a ratchet, short extension and socket or a box-wrench. Turn the plug out by hand, using a rag to shield your fingers from the hot oil. By keeping an inward pressure on the plug as you unscrew it, oil won't escape past the threads and you can remove it without being burned by hot oil.
- Quickly withdraw the plug and move your hands out of the way. Allow the oil to drain completely in the pan, then install and carefully tighten the drain plug. Be careful not to overtighten the drain plug, otherwise you'll be buying a new pan or a trick replacement plug for stripped threads.
Although some manufacturers have at times recommended changing the oil filter every other oil change, we recommend the filter be changed each time you change your oil. The added benefit of clean oil is quickly lost if the old filter is clogged and the added protection to the heart of your engine far outweighs the few dollars saved by using a old filter.
- Move the drain pan under the oil filter. Unless your vehicle is equipped with a canister type filter, use a strap-type or cap-type filter wrench to loosen and remove the oil filter from the engine block. Keep in mind that it's holding about one quart of dirty, hot oil.
- If equipped with a canister filter, remove the through-bolt retaining the canister to the engine, then carefully lower the canister for access to the cartridge. Make sure the old cartridge gasket was lowered with the canister and is not left on the engine. On these vehicles, it is not uncommon to find 2 or more gaskets which were left in place by a less experienced or attentive person who changed the filter before you.
- Empty the old filter into the drain pan and dispose of the filter or the cartridge.
- Using a clean rag, wipe off the filter adapter on the engine block. Be sure that the rag doesn't leave any lint which could clog an oil passage.
Replacement cartridges for canister type filters may be difficult to find. If you cannot locate a replacement cartridge, most automotive supply stores will be able to supply you with an adapter kit which will allow you to use a standard spin-on filter.
- Coat the rubber gasket on the filter or cartridge with fresh oil. If equipped with a standard filter, spin it onto the engine by hand; when the gasket touches the adapter surface, give it another 1 / 2 - 1 / 3 turn. No more, or you'll squash the gasket and it will leak.
- If equipped with a canister filter, install the new cartridge into the canister. Make sure the gasket is in place, then install the canister and tighten the through-bolt.
- Refill the engine with the correct amount of fresh oil. See the refer to the Capacities chart at the end of this section.
- Check the oil level on the dipstick. It is normal for the level to be a bit above the full mark. Start the engine and allow it to idle for a few minutes.
- Shut off the engine and allow the oil to flow back to the crankcase for a minute, then recheck the oil level. Check around the filter and drain plug for any leaks, and correct as necessary.