1999 Toyota Tacoma Oil Leaks
Not every job that HPMotors sees is an engine rebuild, or other large job. Sometimes, it's several smaller jobs combined into a big job. Here's a good example.
This Toyota Tacoma still ran great and seemed to be in good over all condition, but being a higher mileage truck there were several oil seals that had become very hard with age that needed replacing. They were leaking severely, which meant the underside of the engine and subframe were coated with years of oil, grease, and dirt. |
|
|
The first oil leak is a classic. The leaking valve or cam cover gasket right on top of the engine. This vehicle had a major leak at the back of the cover which was causing oil to leak down the back of the engine and onto the exhaust. The cover also has four separate seals to go around the spark plug tubes. These were also incredibly hard. Oil seeping into the spark plug tubes can cause misfires and other running issues, so it's important to get the valve cover seal and those individual tube seals.
The picture to the right shows the top of the engine after the air intake, spark plug wires, part of the wiring wiring harness, and cam cover have all been removed. Now is a good time to highlight why modern engines have cam covers as opposed to valve covers. The valves are underneath the cam shafts in this layout, meaning that the top cover to the engine is actually for the cams first. You can also see the four spark plug tubes in a row down the center of the top of the engine. Four new seals will be installed in the cam cover to go around those tubes along with the cam cover gasket which will go along the outside of the top of the engine. This was the most basic seal to replace, and was wrapped up quickly. |
|
The next seal that was leaking is called the front crank seal, or the front main seal. This is the seal that goes around the crank shaft where it exits the front of the engine block, and is behind the crank damper pulley. That means the grill, radiator, A/C condenser, fan, fan shroud, and belts must be removed first before the damper pulley and the seal can be accessed.
Often times the worn seal on a very high mile motor will actually put a groove in the crank damper pulley. This means that even if you install a new seal, it may not completely take care of the leak. A repair sleeve is installed over the worn groove in the pulley to make sure the new seal has a nice, flat surface to seal against. Follow along with the pictures for details, and a better explanation.
Often times the worn seal on a very high mile motor will actually put a groove in the crank damper pulley. This means that even if you install a new seal, it may not completely take care of the leak. A repair sleeve is installed over the worn groove in the pulley to make sure the new seal has a nice, flat surface to seal against. Follow along with the pictures for details, and a better explanation.
With a new crank damper sleeve and a new front crank seal both installed, it's time to move on to the oil pan.
The oil pan is another classic seal that fails with age. On certain vehicles access to the oil pan is good, keeping the job relatively cheap. On other cars, it can involve completely removing the engine. Fortunately this Tacoma has good oil pan access, and it's not that big of a deal. Since it's the bottom of the engine, the oil pan and block were both covered in a very large layer of dirt and grime. We'll clean up the area as best as possible during the repair.
Follow along with the pictures.
The oil pan is another classic seal that fails with age. On certain vehicles access to the oil pan is good, keeping the job relatively cheap. On other cars, it can involve completely removing the engine. Fortunately this Tacoma has good oil pan access, and it's not that big of a deal. Since it's the bottom of the engine, the oil pan and block were both covered in a very large layer of dirt and grime. We'll clean up the area as best as possible during the repair.
Follow along with the pictures.
So we're all wrapped up, right?
With all those seals take care of, it was believed that all the major leaks were taken care of. That's not always the case. Especially with vehicles that have many leaks, and are very dirty, it can be difficult to find all the leaks the first time.
With all those seals take care of, it was believed that all the major leaks were taken care of. That's not always the case. Especially with vehicles that have many leaks, and are very dirty, it can be difficult to find all the leaks the first time.
So it's time to get that oil filter housing o-ring and gasket. Fortunately, this is another component with decent access, so not a labor heavy job.
With the oil filter housing seals replaced, all the major, observable oil seals have been replaced. The truck may still have a few other drips or drops associated with the transmission or power steering that need be cleared up, but these major oil leaks were the most important. With them taken care of, the truck can be driven for quite a while longer with no worries about running low on oil.