1. Welcome to Tacoma World!

    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 Tacoma discussion topics
    • Communicate privately with other Tacoma owners from around the world
    • Post your own photos in our Members Gallery
    • Access all special features of the site

Cylinder Head Manufacturing Defect?

Discussion in '1st Gen. Tacomas (1995-2004)' started by AWES0ME1, Jul 30, 2020.

  1. Jul 30, 2020 at 7:46 PM
    #1
    AWES0ME1

    AWES0ME1 [OP] Member

    Joined:
    Jul 19, 2020
    Member:
    #334956
    Messages:
    24
    Gender:
    Male
    First Name:
    Jason
    Vehicle:
    98' Tacoma 4x4 2.7
    So this is a bit odd, do you have personal experience with 3rz cylinder heads? I recently received a new from factory OEM head and the cam caps do not have guide pins, is this something any of you have come across?

    20200722_235836.jpg
     
    Last edited: Jul 30, 2020
  2. Jul 31, 2020 at 2:37 AM
    #2
    Wyoming09

    Wyoming09 Well-Known Member

    Joined:
    Apr 24, 2015
    Member:
    #153833
    Messages:
    9,902
    Gender:
    Male
    New Tripoli Pa
    Vehicle:
    2000 Work truck 5 speed 4x4 3.4
    Super Springs
    Might be the new vendor for the head no longer machines the caps like before.

    The quality control girl was out to lunch on yours.

    I have only ever seen the original with the engine.
     
    AWES0ME1 [OP] likes this.
  3. Aug 1, 2020 at 12:39 AM
    #3
    AWES0ME1

    AWES0ME1 [OP] Member

    Joined:
    Jul 19, 2020
    Member:
    #334956
    Messages:
    24
    Gender:
    Male
    First Name:
    Jason
    Vehicle:
    98' Tacoma 4x4 2.7
    I called LC engineering and they said the new heads aren't coming machined with pins, I'm concerned that I won't get proper cam clearance in my journal tolerances, should I be concerned?
     
  4. Aug 1, 2020 at 1:16 AM
    #4
    Wyoming09

    Wyoming09 Well-Known Member

    Joined:
    Apr 24, 2015
    Member:
    #153833
    Messages:
    9,902
    Gender:
    Male
    New Tripoli Pa
    Vehicle:
    2000 Work truck 5 speed 4x4 3.4
    Super Springs
    One way to check plastigage ( follow the directions) if you don`t have an inside and outside micrometers of the correct size
     
  5. Aug 1, 2020 at 10:25 AM
    #5
    AWES0ME1

    AWES0ME1 [OP] Member

    Joined:
    Jul 19, 2020
    Member:
    #334956
    Messages:
    24
    Gender:
    Male
    First Name:
    Jason
    Vehicle:
    98' Tacoma 4x4 2.7
    The thing with plastigage is that I would need to remove the caps once again to check, I'm more concerned that the rotational movement of the cap without the pins, would this cause quenching if not properly aligned and poor oil flow along the journals.
     
    Last edited: Aug 1, 2020
  6. Aug 1, 2020 at 10:54 AM
    #6
    tacokarl

    tacokarl Big Blue

    Joined:
    Aug 16, 2015
    Member:
    #161934
    Messages:
    77
    Gender:
    Male
    First Name:
    Karl
    Connecticut
    Vehicle:
    2008 Pre-Runner DCLB
    a good machine shop should have no issue making you a insert to fill that void, you could even go one step further and have them inset a counter bore in the cap and have extended insert that acts as a guide pin.
     
    billybop90 and AWES0ME1 [OP] like this.
  7. Aug 1, 2020 at 11:13 AM
    #7
    AWES0ME1

    AWES0ME1 [OP] Member

    Joined:
    Jul 19, 2020
    Member:
    #334956
    Messages:
    24
    Gender:
    Male
    First Name:
    Jason
    Vehicle:
    98' Tacoma 4x4 2.7
    This is a good option, I was thinking I'd just have pins pressed in and machine the caps to accept such, I'd need to line hone again though and that's what concerns me because the cam journal tolerances would probably be over spec and as far as I know they do not make bearings for these heads. I believe the heads should have been machined properly in the first place so I'm a bit confused, usually manufacturers press in pins then line hone. Did Toyota deem the cam cap pins unnecessary for assembly? Or do you think this would be a factory defect?
     
    cruiserguy likes this.
  8. Aug 1, 2020 at 11:18 AM
    #8
    Abeyancer

    Abeyancer Well-Known Member

    Joined:
    Mar 28, 2019
    Member:
    #288326
    Messages:
    1,245
    Gender:
    Male
    Vehicle:
    98 4x4 ex cab tacoma 3rz


    I'm going to say yes they deemed them unnecessary.. or at the very least, an acceptable cost cutting measure.

    I bought a chinesium head for my 3rz that came fully assembled but the timing was off. When I took the cams out to fix it I know my caps looked like that. I have 1500 miles on that new head and no issues with the motor what so ever
     
    cruiserguy and AWES0ME1 [OP] like this.
  9. Aug 1, 2020 at 11:23 AM
    #9
    AWES0ME1

    AWES0ME1 [OP] Member

    Joined:
    Jul 19, 2020
    Member:
    #334956
    Messages:
    24
    Gender:
    Male
    First Name:
    Jason
    Vehicle:
    98' Tacoma 4x4 2.7
    Right on! LCE said the same thing and even told me they were running 700hp no problems. I may be a bit too concerned about longevity.. thanks for sharing your experience.
     
    cruiserguy and Abeyancer like this.
  10. Aug 1, 2020 at 11:24 AM
    #10
    cruiserguy

    cruiserguy Well-Known Member

    Joined:
    Jul 31, 2016
    Member:
    #193416
    Messages:
    18,955
    Gender:
    Male
    First Name:
    Elijah
    SLC
    Vehicle:
    2000 ext cab, 2.7L, auto, 4x4
    I don't have an answer, I can tell you have more experience than I. Your scenario got me curious to see how Toyota shows the head in their part diagrams. Just sharing in case it can help here
    https://partsouq.com/en/catalog/gen...qO_w6_6zAAAAAMwDT3Y$&vid=0&cid=&uid=284524&q=
    111360A.jpg
     
    AWES0ME1 [OP] likes this.
  11. Aug 1, 2020 at 11:32 AM
    #11
    AWES0ME1

    AWES0ME1 [OP] Member

    Joined:
    Jul 19, 2020
    Member:
    #334956
    Messages:
    24
    Gender:
    Male
    First Name:
    Jason
    Vehicle:
    98' Tacoma 4x4 2.7
    I believe Toyota calls for 20 pins, there were only 4 pins installed, they were under the first two caps (towards the front).
     
    cruiserguy likes this.
  12. Aug 1, 2020 at 9:19 PM
    #12
    Jeff Lange

    Jeff Lange Well-Known Member

    Joined:
    May 19, 2015
    Member:
    #155616
    Messages:
    1,375
    Edmonton, AB
    Vehicle:
    '86 AE86, '05 NCP13, '11 GSE21
    Toyota used 20 pins up to December 1998, heads manufactured from December 1998 onward only use 4 pins.

    20-pin Heads:
    11101-79186

    4-pin Heads:
    11101-79265
    11101-79266
    11101-79275
    11101-79276

    Jeff
     
    AWES0ME1 [OP] and cruiserguy like this.
  13. Aug 1, 2020 at 11:07 PM
    #13
    AWES0ME1

    AWES0ME1 [OP] Member

    Joined:
    Jul 19, 2020
    Member:
    #334956
    Messages:
    24
    Gender:
    Male
    First Name:
    Jason
    Vehicle:
    98' Tacoma 4x4 2.7
    Wow, I really appreciate the information! Thank you

    Do I simply assemble the head or is there a special procedure that will ensure the tolerances are within spec?
     
  14. Aug 2, 2020 at 9:54 AM
    #14
    tacokarl

    tacokarl Big Blue

    Joined:
    Aug 16, 2015
    Member:
    #161934
    Messages:
    77
    Gender:
    Male
    First Name:
    Karl
    Connecticut
    Vehicle:
    2008 Pre-Runner DCLB
    Definitely not a defect, most likely they were found to be unnecessary and further ruled out for cost saving.
     
  15. Aug 2, 2020 at 8:02 PM
    #15
    Jeff Lange

    Jeff Lange Well-Known Member

    Joined:
    May 19, 2015
    Member:
    #155616
    Messages:
    1,375
    Edmonton, AB
    Vehicle:
    '86 AE86, '05 NCP13, '11 GSE21
    No special procedure, plastigage and follow the torque sequence for the cap caps. Same same.

    Jeff
     
    AWES0ME1 [OP] likes this.
  16. Aug 2, 2020 at 8:08 PM
    #16
    AWES0ME1

    AWES0ME1 [OP] Member

    Joined:
    Jul 19, 2020
    Member:
    #334956
    Messages:
    24
    Gender:
    Male
    First Name:
    Jason
    Vehicle:
    98' Tacoma 4x4 2.7
    Much appreciated, I was worrying myself thinking that if the caps weren't perfectly aligned that it could possibly impare the oil flow between the cam and the caps. I was thinking that if the cap was twisted one way or the other could cause oil starvation on one side of the surface and low pressure on the other. So you say I should simply check the tolerances with plastigage then assemble? Do you have any tips on keeping it somewhat aligned better during the final assembly?
     
  17. Aug 2, 2020 at 8:34 PM
    #17
    DrZ

    DrZ Well-Known Member

    Joined:
    Dec 14, 2014
    Member:
    #144262
    Messages:
    1,299
    Gender:
    Male
    Mesa, AZ
    Vehicle:
    96 2.4L 5-speed
    I wonder if the pins will still fit if you really want them. I came up with this part number.

    https://www.toyotapartsdeal.com/oem...camshaft~bearing~cap~setting~90253-10006.html

    I believe it will show the number required as either 4 or 20 depending on year. The pins should be included with the head if you got the complete head from Toyota, but again that could be 4 or 20 pins depending on cylinder head part number.
     
  18. Aug 2, 2020 at 8:40 PM
    #18
    Jeff Lange

    Jeff Lange Well-Known Member

    Joined:
    May 19, 2015
    Member:
    #155616
    Messages:
    1,375
    Edmonton, AB
    Vehicle:
    '86 AE86, '05 NCP13, '11 GSE21
    Not really, things should be quite aligned by the cam itself, though I understand the oil clearances are quite small. If anything I'd say use a thicker assembly lube and make sure it's spread pretty evenly. Not much you can do beyond that. How is the bolt to cap bore clearance? Is it pretty loose or relatively tight?

    It looks like the head side has the counterbore for the pins to fit into, but the cam caps do not. So you wouldn't be able to just add the pins without machining the cam caps.

    Jeff
     
    DrZ and AWES0ME1 [OP] like this.
  19. Aug 2, 2020 at 9:06 PM
    #19
    AWES0ME1

    AWES0ME1 [OP] Member

    Joined:
    Jul 19, 2020
    Member:
    #334956
    Messages:
    24
    Gender:
    Male
    First Name:
    Jason
    Vehicle:
    98' Tacoma 4x4 2.7
    Brilliant Jeff! That's very concise and valuable information with the assembly lube, thank you very much! The bolt hole bore clearances are somewhat loose around the shaft of the bolt, that was actually the first thing I checked upon noticing the pins, I would say there's maybe ~.05-1.0mils of movement though I'll have to check again soon and I'll certainly let you know. Greatly appreciate the conversation, thank you!
     

Products Discussed in

To Top