Results 1 to 11 of 11

Thread: Mark Maras

  1. #1
    Registered User
    Member ID
    CZCC-29883
    Join Date
    Nov 2013
    Location
    Portland, Or
    Age
    71
    Posts
    283

    Default Mark Maras

    Water in the oil!
    I have an engine out of a 74-260 Z that reportedly has a blown head gasket with water in the oil. After pulling the pan and head, the inside looks pristine. The engine has 92,00 original miles on it. The oil doesn't have much water in it. The color is dark grayish brown and very opaque. Evidently the engine was not run very long with the emulsion of oil and water.
    My question is if the head gasket is not leaking, where did the water come from? The only place in the head gasket that looked bad was up front where it overlaps the front cover.
    This is the original engine out of the 260 & I'd like to use it. I'd appreciate any and all ideas that you may have.
    I will be pulling the 75 engine out, that came in the car, and will probably sell it to finance more restoration. I also have a complete 71 Z with a very rusted out body but full of very usable parts if any one is interested. location is Portland, Oregon.
    Thanks
    Mark

  2. #2
    Registered User madkaw's Avatar
    Member ID
    CZCC-7622
    Join Date
    Dec 2004
    Location
    bloomington IN
    Age
    57
    Posts
    2,288

    Default

    Look again at the HG very closely - maybe you are missing something. It might have been easier to diagnose as a running engine.
    FYI - if the 71 still has a motor ( head more importantly) , I would strongly consider using it on the L26 block. Especially if it is an earlier e-88 head.
    Steve
    71 240z,bw-5sp 2.4-40 over,balanced,e-88,big valves,ported&polished, stage2,header, triple Mikuni's 40's
    3.90 Subaru STI LSD

  3. #3
    Registered User
    Member ID
    CZCC-29883
    Join Date
    Nov 2013
    Location
    Portland, Or
    Age
    71
    Posts
    283

    Default

    Thanks For the info. The 71 Z is complete. What are the advantages in using the head and cam from the 71? The 74 engine does have notched cylinders.
    Am I to assume the head gasket is the only place that will leak water into the oil with the possible exception of a cracked block?
    Mark

  4. #4
    Registered User Oiluj's Avatar
    Member ID
    CZCC-15388
    Join Date
    Nov 2007
    Location
    SF Bay Area
    Age
    66
    Posts
    1,746

    Default

    You might also want to check condition of the freeze plug under the front cover when you have the head off.
    Julio
    1972 240Z (in-progress, 95% complete)
    CZC# 15388

  5. #5
    Registered User
    Member ID
    CZCC-29883
    Join Date
    Nov 2013
    Location
    Portland, Or
    Age
    71
    Posts
    283

    Default

    Thanks I'll do that. Any other places to check?
    Mark

  6. #6
    Registered User madkaw's Avatar
    Member ID
    CZCC-7622
    Join Date
    Dec 2004
    Location
    bloomington IN
    Age
    57
    Posts
    2,288

    Default

    Do some research on coolant is the oil and check all possibilities. Don't read about too many cracked blocks, they are pretty tough.
    What month is the 71? The combustion chamber is better on the early e-88's then the later year/months. Earler head will have smaller chambers and better quench.
    Steve
    71 240z,bw-5sp 2.4-40 over,balanced,e-88,big valves,ported&polished, stage2,header, triple Mikuni's 40's
    3.90 Subaru STI LSD

  7. #7
    Z geek at large FastWoman's Avatar
    Member ID
    CZCC-19635
    Join Date
    Jul 2009
    Location
    Hampton Roads, VA
    Posts
    2,787

    Default

    It's a long shot, but the front-most bolt of the thermostat housing threads into a through-hole that enters the timing chain area right behind the guide/tensioner. Vacuum in the engine vs. pressure in the coolant system... bad thermo housing gasket, perhaps a crack somewhere... Who knows?
    My last three sports cars while I still owned all three:

    2001 BMW Z3 Roadster 3.0i soft/hard top (sold)
    1966 Ford Mustang Coupe (sold)
    1978 Datsun 280Z (enjoying very much )

  8. #8
    Registered User black gold man's Avatar
    Member ID
    CZCC-22534
    Join Date
    Sep 2010
    Location
    Detroit, Michigan, United States
    Age
    58
    Posts
    821

    Default

    where did the water come from? Condensation maybe.
    If the car was not ran until the motor was up to high temp more then just watching the gauge going to 180 you can get water in motor.
    Even just sitting a cold motor can condensate when temp outside gets warm and moist just like your beer.

  9. #9
    Registered User
    Member ID
    CZCC-29883
    Join Date
    Nov 2013
    Location
    Portland, Or
    Age
    71
    Posts
    283

    Default

    Thanks Guys
    I'll check the thermostat housing. I've considered condensation. I don't know much about the history of the engine, When I pulled the pan the oil was an emulsion with some separate water. The engine appears to only have 92,000 miles on it. Not even a ridge in the top of the cylinders. After checking everything I can, I'm going to pull the 75 engine out and reinstall the original 74 engine.
    I'm open to any and all suggestions on this project. Keep em coming.
    Thanks
    Mark

  10. #10
    Former frequent poster sblake01's Avatar
    Member ID
    CZCC-3797
    Join Date
    Mar 2003
    Location
    San Bernardino, Ca. U.S.A.
    Age
    69
    Posts
    10,574

    Default

    I once had an L series 4 cylinder develop a crack in the housing behind the water pump. The spring that keeps the radiator hose from collapsing somehow had got into the water pump impeller and it scraped a hole in the cover.
    2004 Ford Ranger EDGE Supercab
    (@Moonpup: This one really is an EDGE!)
    2005 Pontaic GTO
    2010 Mercedes Benz C300 AMG Sportline (Wife's car)
    2014 Kia Rio LX (Wife's daily driver)
    Certified HVAC/MVAC Technician

  11. #11
    Registered User
    Member ID
    CZCC-29883
    Join Date
    Nov 2013
    Location
    Portland, Or
    Age
    71
    Posts
    283

    Default

    That sounds like another excellent place to check. As I'm cleaning it, haven't started yet, I'm going to inspect all surfaces of the water jacket in the head and block. If I should find anything suspect, does anyone out there have any ideas or experience with testing methods to confirm damage or is this going to be obvious?

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. Timing mark
    By mjr45 in forum Engine and Drivetrain (S30)
    Replies: 8
    Last Post: 01-13-2011, 05:02 AM
  2. Meet Your New Koreisha Mark
    By Mike in forum Publications
    Replies: 0
    Last Post: 08-19-2010, 12:31 AM
  3. timing mark?
    By Linkstar07 in forum Engine and Drivetrain (S30)
    Replies: 10
    Last Post: 07-09-2007, 06:49 PM
  4. New Z Making its Mark
    By Alfadog in forum Open Discussions
    Replies: 1
    Last Post: 05-26-2003, 01:28 AM

Bookmarks

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
  •