Results 1 to 8 of 8

Thread: 1961 Mark 2 Gearbox overheating

  1. #1
    Junior Member
    Join Date
    Jul 2020
    Location
    Eye Suffolk
    Posts
    3
    Post Thanks / Like

    1961 Mark 2 Gearbox overheating

    Hi I have just bought a mark 2 1961. The gearbox which was rebuilt last year gets very hot very quickly-also the overdrive is a bit clunky when disengaging-any ideas?

  2. #2
    Senior Member
    Join Date
    Apr 2008
    Location
    Further up the creek.
    Posts
    993
    Post Thanks / Like
    Sounds like the wrong type of oil in the gearbox.

    Now please check this, for my memory is not what it used to be (!) but (I think) it should be SAE 30 oil for the earlier Moss box and EP90 for the later all-synchro box.

    I think your 1961 example would have a Moss box (but please check, as it may have been changed). So if (for example) your Moss box has been filled with EP90, this could lead to the symptoms described.

    Whatever, first thing to do is identify the box, then drain and refill with the correct oil. Then see how it goes.
    2000 Jaguar X308 4.0
    1973 Jensen Interceptor Mk III 7.2
    1969 Jensen Interceptor Mk I 6.3

  3. Dislikes Zero123 disliked this post
  4. #3
    Junior Member
    Join Date
    Jul 2020
    Location
    Eye Suffolk
    Posts
    3
    Post Thanks / Like
    Thanks for that-local garage have suggested it could be a bad earth so have had this sorted and just need to test it.

  5. #4
    Senior Member
    Join Date
    May 2011
    Posts
    285
    Post Thanks / Like
    Agree oil is important based on type of gearbox. Re overdrive being ‘clonky’ when disengaging, this is fairly normal if you don’t depress the clutch whilst coming out of overdrive.
    PETER DAVIES, 2016 XF 2.0 diesel Portfolio. 1967 Mark2 (240.)

  6. #5
    Senior Member
    Join Date
    Feb 2016
    Location
    OSWESTRY, Shropshire
    Posts
    1,801
    Post Thanks / Like
    Hello Peter,

    forgive me but the idea of using a clutch with the overdrive is nonsense. Use the switch, that is all that is needed.

    As a general view of the original post, it's unusual for the disengagement to be a problem. Common problems are lack of engagement, usually electrical but sometimes due to worn clutches.

    Alec
    MK 2 3.8 (Long term restoration), 2.5 P.I. Triumph saloon, 564 Hymer motorhome.

  7. #6
    Senior Member
    Join Date
    May 2011
    Posts
    285
    Post Thanks / Like
    Alec,
    I’ve had my 240 over thirty years and have always found that if you change down from overdrive to direct at higher speeds there is a definite jerk as the switch engages and increases the revs. Dipping the clutch makes for a much smoother drive.

    Offered my opinion in good faith. Don’t appreciate it being called nonsense!
    PETER DAVIES, 2016 XF 2.0 diesel Portfolio. 1967 Mark2 (240.)

  8. #7
    Senior Member
    Join Date
    Feb 2016
    Location
    OSWESTRY, Shropshire
    Posts
    1,801
    Post Thanks / Like
    Hello Peter,

    I use nonsense literally, I also could have said illogical. Dipping the clutch does nothing to match the car speed, engine speed relative to the gear. Yes, you can slowly engage the clutch and drag engine speed up at the expense of extra clutch wear, although you said dip. A simple increase in engine speed using the throttle is my preferred way and I can easily match your 30 years of overdrive use.
    I apologise for being forthright and meant no offence.

    Alec
    MK 2 3.8 (Long term restoration), 2.5 P.I. Triumph saloon, 564 Hymer motorhome.

  9. #8
    Senior Member cass3958's Avatar
    Join Date
    Jun 2014
    Location
    Torquay Devon
    Posts
    290
    Post Thanks / Like
    Cannot comment on a Jaguar overdrive as my S type is an Auto but I had an MGB GT V8 with overdrive on a column switch. Going up the overdrive was just a fifth gear. Coming down it was an over taking gear. To change down you put your right foot flat on the floor and flicked the switch and the car would go off like a scalded cat. I was in my twenties and sometime felt like a definite jerk but it put a smile on my face.
    Rob.C.
    1968 Jaguar S Type 3.4 Auto Old English white
    2006 X type SE 2.0d Estate
    1966 Ford Anglia 1760 X flow
    1993 Yamaha FJ1200
    2012 Old English Sheep Dog White and Grey

Posting Permissions

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