1. Welcome to 4Runners.com!

    You are currently viewing as a guest! To get full-access, you need to register for a FREE account.

    As a registered member, you’ll be able to:
    • Participate in all 4Runner discussion topics
    • Transfer over your build thread from a different forum to this one
    • Communicate privately with other 4Runner owners from around the world
    • Post your own photos in our Members Gallery
    • Access all special features of the site

Oil leak above oil pan

Discussion in '2nd Gen 4Runners (1990-1995)' started by Ryan95, Jan 30, 2019.

  1. Jan 30, 2019 at 5:02 AM
    #1
    Ryan95

    Ryan95 [OP] New Member

    Joined:
    Jan 29, 2019
    Member:
    #8611
    Messages:
    4
    Gender:
    Male
    Vehicle:
    95 Toyota 4runner 3.0
    I have a pretty good size oil leak coming from above the oil pan. Just purchased this 1995 Toyota 4Runner 3.0 automatic the other day. The leak looks to be coming from the same area as the water pump. Any suggestions or information is greatly appreciated. Thanks
     
  2. Feb 17, 2019 at 10:53 AM
    #2
    Quietgiant

    Quietgiant New Member

    Joined:
    May 2, 2015
    Member:
    #587
    Messages:
    3
    First Name:
    Mart
    Vehicle:
    1992 and 1994 4Runner V6 4x4
    Take a look at the oil cooler (drivers side above the oil pan). sometimes oil will follow the oil line to the cooler and drip towards the front.
     
    HoBoDanny likes this.
  3. Feb 17, 2019 at 10:58 AM
    #3
    HoBoDanny

    HoBoDanny Dude...

    Joined:
    Feb 5, 2019
    Member:
    #8697
    Messages:
    966
    Gender:
    Male
    First Name:
    Daniel
    Kentucky
    Vehicle:
    2004 SR5 V6 4WD 4Runner
    RCI Skid Plate CBI Ditch Light Brackets Hankook DynaPro ATM RF10 265 70R17 113T Tires 1.25” Wheel Spacers TPMS Bypass Mod Hydrocarbon Filter Removed Merca decal 2” leveling kit front only Black headlights
    Could also check valve cover gaskets.
     
  4. Feb 25, 2019 at 1:58 PM
    #4
    atgparker

    atgparker Cal Poly, ETME 1988

    Joined:
    Jun 20, 2018
    Member:
    #6296
    Messages:
    328
    Gender:
    Male
    First Name:
    Andrew
    Mission Viejo, CA
    Vehicle:
    1991 White 4Runner 3.0 L
    Rebuilt Engine MLS and ARP on the heads, DT Header, 2-1/2" CARB compliant Flow-Master CAT with 2.0" Bosal CAT back Dayco 1-1/4" Spacers, SkyJacker M-Series Monotube Shocks, Ball Joint Spacers. 95-9006 K&N Air Cleaner, G-Plus Alum Radiator, ZIrgo 16" Fan, Derale Temp switch/relay
    Having just rebuilt my 3VZ-E., I would suspect the problem lies within the cast aluminum oil pump housing which adorns the front of the block. It is below the water pump and carries the front main seal for the crank shaft. So it might be this seal or on the oil filter and oil cooler side of the block is the main oil pressure feed port in the engine which is adjacent to the oil pressure sending unit that is directly below the alternator and in front of the oil filter. The oil pumps output goes into the block and through an o-ring seal that is used to couple the oil pump housings oil pressure output into the block. When I rebuilt mine I used a new o-ring and sealed the flange surfaces that are common to the block with Loctite 515 anaerobic gasket maker. There is additional flange surface area that surrounds this oil pressure port that is external to the o-ring groove. So I doctored this area as well with the 515 for redundant sealing. When I checked the original OEM ASIAN oil pump for wear which it didn't have any to measure I thought that the 2.5 psi out put at idle seems a bit low which is standard specification in the FSM. So, I placed a washer under the spring on the pressure relief plunger to boost the pressure output in the pump . As this port into the engine block is a gland seal between the oil pump housing and the engine block and has all of the oil pressure out put in it, the potential for a leak with a degraded or perished seal in this region is very suspect if it is a substantial leak on your rig! But to get at this require timing belt removal and then harmonic balancer removal and the sproket for the TB has to come off. Then the oil pump housing can be removed with as there are a series of M6 screws that enter the engine block and some also which are part of the splash shield and oil pan which could be hard to reseal if they are not redone completely with engine removed from the vehicle if its 4WD.

    As for the OEM oil cooler it does not have any oil lines because the oil remains resident with in the cylindrical housing that is the unit. The oil cooler utilizes engine coolant and is basically a mini-heat-exchanger that takes some heat from the engine oil by subjecting it to the coolant. There are OEM seals on the block and under the large screw that fixes this to the engine blocks cast in features. All the pressure from the oil pumps output go through the oil filter and the oil cooler before they go into the oil feed galleries for the main bearing and crankshaft and then off up to the cams and cam buckets in the heads. The pair of "rubber" hoses on the oil cooler are coolant lines not oil lines. The forward coolant line comes from the water pump and the other exits from the oil cooler housing and back into a water gallery in the engine block. The one from the water pump goes right under the oil filter and is held in a sprung bracket and is usually covered with oil from shade three oil changes!

    I hope this explanation helps in your diagnosis?
     

Products Discussed in

To Top