GM Inside - Ford Inside - Ford Ranger - Jeep - American Muscle

Support FSC and see no ads! - Click Here
Results 1 to 8 of 8

98 Z71 Overheated

This is a discussion on 98 Z71 Overheated within the Technical / Maintenance forums, part of the General Discussion category; My 1998 Z71 overheated and now has a miss and the radiator is getting back pressure. I believe this is ...

  1. #1
    Registered User
    Join Date
    Oct 2009
    Location
    Texas
    Posts
    8

    98 Z71 Overheated


    Support FSC and see no ads! - Click Here
    My 1998 Z71 overheated and now has a miss and the radiator is getting back pressure. I believe this is a blown head gasket, cracked head or warped head. I hear that the Vortec heads are bad to warp or crack when overheated. what do I do next? What other problems am I possibly facing?

  2. #2
    Registered User daved931's Avatar
    Join Date
    Apr 2008
    Location
    Bangor, ME
    Age
    32
    Posts
    4,065

    Re: 98 Z71 Overheated

    I would think the iron Vortec heads are fairly resistant to warping, but it all depends upon how hot you got things.

    Maybe start with a compression test on each cylinder?
    1999 2 Door Tahoe 4x4 w/ 14 Bolt SF & TruTrac. Corvette servo, Gibson cat-back, custom tune from Black Bear, AD244 alt. upgrade, Z71 skid plates, Escalade cluster, 2" block + 1.5" crank, 285/75R16 SOLD 1/2012
    2008 Silverado 1500 Z71, Borla catback, block and coil spacer

  3. #3
    0_o o_0 0_o o_0 98GreenMachine's Avatar
    Join Date
    Aug 2005
    Location
    St. Paul, MN
    Age
    29
    Posts
    5,583

    Re: 98 Z71 Overheated

    What do you mean by 'the radiator is getting back pressure'?
    08 HHR LS - 2.2 | 5 speed | 30 MPG

    98 K1500 Z71 - 204k | L31 | 60E | 3.73's | 3" BL | 33x12.5x15 Dick Cepek F-C II's | Dynomax Ultra Flo X DI/DO | 14 MPG

    84 S15 Jimmy 2dr 4x4 - engine/tranny all rebuilt

  4. #4
    Registered User jake760's Avatar
    Join Date
    May 2009
    Location
    USA
    Age
    24
    Posts
    672

    Re: 98 Z71 Overheated

    Sounds like a blown head gasket. X2 on checking compression across cylinders. What did you do to make it overheat?

  5. #5
    Registered User
    Join Date
    Oct 2009
    Location
    Texas
    Posts
    8

    Re: 98 Z71 Overheated

    My son was driving it, who knows. I think the water pump has leaking weep hole and he has not checked the water apparantly.

  6. #6
    Registered User
    Join Date
    Oct 2009
    Location
    Texas
    Posts
    8

    Re: 98 Z71 Overheated

    When you turn the engine over the radiator will build up pressure. I had a 91 350 overheat by the other son and it did the same thing, the heads were warped on it.

  7. #7
    Registered User daved931's Avatar
    Join Date
    Apr 2008
    Location
    Bangor, ME
    Age
    32
    Posts
    4,065

    Re: 98 Z71 Overheated

    That's just compression leaking from the combustion chamber into the cooling system though, right?
    1999 2 Door Tahoe 4x4 w/ 14 Bolt SF & TruTrac. Corvette servo, Gibson cat-back, custom tune from Black Bear, AD244 alt. upgrade, Z71 skid plates, Escalade cluster, 2" block + 1.5" crank, 285/75R16 SOLD 1/2012
    2008 Silverado 1500 Z71, Borla catback, block and coil spacer

  8. #8
    Registered User
    Join Date
    Oct 2009
    Location
    Texas
    Posts
    8

    Re: 98 Z71 Overheated

    Yes I am assuming if the head is cracked, warped, or the gasket is blown the pressure build up in the radiator is from the compression of the motor cylinder or cylinders that is leaking

 

 

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •