Which radiator cap please?
  • Register
  • Help
Results 1 to 21 of 21
  1. #1
    Tadpole
    Join Date
    Apr 2012
    Location
    Melbourne
    Posts
    21

    Default Which radiator cap please?

    Hello All,

    I did a really stupid thing recently when checking the water level in my 1976 Peugeot 504 LTI- I left the radiator cap off and drove off without it! The cap of course is long since gone and I wasn't too sure what psi to replace it with... I think 4 psi is correct and that's what the fellow at Autobarn came up with, after looking in a large bible, but if anyone could please confirm I've got the correct cap before I drive to work tomorrow, that would be grand!

    Thanks so much!

    Advertisement

  2. #2
    1000+ Posts Wildebeest's Avatar
    Join Date
    Oct 2004
    Location
    Perth Western Australia
    Posts
    2,694

    Default

    Madame Peugeot,
    The Autobarn guy is correct. 4lb/sq".
    If you have a recovery container you will need a special 4lb/sq".
    For now carry on with the first type.

    PS. Be careful when selecting a cap one type has a long spring. Mini.

  3. #3
    Tadpole
    Join Date
    Apr 2012
    Location
    Melbourne
    Posts
    21

    Default

    Hey thanks Wildebeest!

    Excuse my terrible ignorance, but what is a recovery container and how do I know if I have one please?
    And the cap I selected didn't have a long spring, it was the usual flat type, similar to what I had before...My previous 1979 Pug had one with the long spring, so I know which one you're referring to...

  4. #4
    Fellow Frogger! 505604's Avatar
    Join Date
    Jul 2002
    Location
    Junee, NSW
    Posts
    753

    Default

    If you slightly overfill the radiator, where does the excess go - down a little pipe and onto the ground, or into a bottle?
    Most likely onto the ground, and if so, you don't have a recovery container.

    Andrew
    Current cars: Peugeot 307 HDi Touring; Peugeot 306 Cabriolet; Peugeot 406 HDi, Peugeot 505 Familiale
    Previous cars: 1965 Peugeot 404; 1972 Renault 16TS; 1970 Peugeo 504 1800; 1978 Peugeot 504 GL; 1976 Peugeot 504 LTI; 1984 Peugeot 505 Familiale; 1982 Peugeot 604 (converted to TD) 1999 Peugeot 306 Cabriolet

  5. #5
    1000+ Posts Wildebeest's Avatar
    Join Date
    Oct 2004
    Location
    Perth Western Australia
    Posts
    2,694

    Default

    Madame,
    If your 504 doesn't have a recovery system the rad overflows onto the ground. [see Andrew's post *4].
    With a recovery system the overflow pipe runs into a small tank/bottle.
    Because of the different valve design in the rad cap the coolant can exit to the bottle with the system, warm, then return from the bottle when cool.
    This makes for a sealed system keeping air from the coolant [corrosion].
    Without a recovery cap you will find that your coolant level will be one and a half to two inches below the cap. This is normal, topping it up is pointless it will just make its own level.

    PS. I have a part number somewhere for the recovery cap should you think of fitting a sealed system. I will put the number up later.

  6. #6
    Fellow Frogger!
    Join Date
    Jul 2005
    Location
    Melbourne
    Posts
    328

    Default

    Fairly sure I have a spare cap. PM if you're still after one, I'm in east Brunswick.
    '96 Peugeot 405 SRDT Station Wagon

    '71 Peugeot 504 GL - gone

    '91 Peugeot 205si - gone

  7. #7
    1000+ Posts Wildebeest's Avatar
    Join Date
    Oct 2004
    Location
    Perth Western Australia
    Posts
    2,694

    Default Radiator cap ?

    Madame P,
    As promised the part number for the 4lb/sq" recovery cap is.. 1305.07 [bouchon].

  8. #8
    Tadpole
    Join Date
    Apr 2012
    Location
    Melbourne
    Posts
    21

    Default

    Thanks Wildebeest,

    I had a look and sure enough, I don't have a recovery container, the tube just overflows onto the ground. So, I think I have the right cap and all is well! Thanks so much for all your help!

  9. #9
    Tadpole
    Join Date
    Apr 2012
    Location
    Melbourne
    Posts
    21

    Default

    Thanks so much for the offer, however I appear to have purchased the correct cap from Autobarn, so all is well. I'm in Brunswick, so might see you tootling about!

  10. #10
    Fellow Frogger!
    Join Date
    Jul 2005
    Location
    Melbourne
    Posts
    328

    Default

    No doubt! There are a few around here. I'm the 'sage grey' (light green) early GL.
    '96 Peugeot 405 SRDT Station Wagon

    '71 Peugeot 504 GL - gone

    '91 Peugeot 205si - gone

  11. #11
    VIP Sponsor
    Join Date
    Nov 2010
    Location
    melbourne Australia
    Posts
    74

    Default

    They were originally 4psi however this does little to raise the boiling point of the coolant and hence I have always retrofitted with a 7psi Cap which is ideal and generally easier to obtain!

    You cannot go any higher than this without chance of damage/leakage owing to the inherantly weak Top Radiator Tanks of 504's.

    Make sure the Cap you obtain is the 'Short spring", not the "long spring"

    Paris Jansen.

    Quote Originally Posted by scatterbrain View Post
    No doubt! There are a few around here. I'm the 'sage grey' (light green) early GL.
    Last edited by 504freak; 18th April 2012 at 10:28 AM. Reason: spelling error

  12. #12
    1000+ Posts Wildebeest's Avatar
    Join Date
    Oct 2004
    Location
    Perth Western Australia
    Posts
    2,694

    Default cap

    Quote Originally Posted by 504freak View Post
    They were originally 4psi however this does little to raise the boiling point of the coolant and hence I have always retrofitted with a 7psi Cap which is ideal and generally easier to obtain!

    You cannot go any higher than this without chance of damage/leakage owing to the inherantly weak Top Radiator Tanks of 504's.

    Make sure the Cap you obtain is the 'Short spring", not the "long spring"

    Paris Jansen.

    Paris,
    Yes on all three comments although No 1, the raising of the boiling pressure shouldn't be necessary if the system is in good nick.

    It was written somewhere that the 404/504 systems didn't rely on pressure, the low 4lb/" cap designed purely to contain the coolant. Anyone?

  13. #13
    VIP Sponsor
    Join Date
    Nov 2010
    Location
    melbourne Australia
    Posts
    74

    Default

    I have to dis-agree. 404/504's are typically under-cooled and also suffer Radiator blockages more so than almost any other make/model and are also prone to Head Gasket failures. Hence they need all the Help they can get....

    Raising the Boilng point of any cooling system is desirable. Once a system bolis it's all over.

    You are correct in stating that raising the boiling point shoudn't be necessary if the cooling system is in good nick, however I'd argue most arent. Even when they are, wait 12 months and they likley wont be.

    One of the most common conversions I perform to 504's in my workshop is to fit later 505 cross-flow radiators. This not only dramatically improves cooling efficiency but also allows the running of a 13psi Cap. The addition of an expansion bottle also reduces the need to frequentlyTop-up the cooling system.

    Paris


    QUOTE=Wildebeest;1054455]Paris,
    Yes on all three comments although No 1, the raising of the boiling pressure shouldn't be necessary if the system is in good nick.

    It was written somewhere that the 404/504 systems didn't rely on pressure, the low 4lb/" cap designed purely to contain the coolant. Anyone?[/QUOTE]

  14. #14
    1000+ Posts robmac's Avatar
    Join Date
    Nov 2004
    Location
    Melbourne / Caulfield
    Posts
    19,211

    Default

    Quote Originally Posted by 504freak View Post
    I have to dis-agree. 404/504's are typically under-cooled and also suffer Radiator blockages more so than almost any other make/model and are also prone to Head Gasket failures. Hence they need all the Help they can get....

    Raising the Boilng point of any cooling system is desirable. Once a system bolis it's all over.

    You are correct in stating that raising the boiling point shoudn't be necessary if the cooling system is in good nick, however I'd argue most arent. Even when they are, wait 12 months and they likley wont be.

    One of the most common conversions I perform to 504's in my workshop is to fit later 505 cross-flow radiators. This not only dramatically improves cooling efficiency but also allows the running of a 13psi Cap. The addition of an expansion bottle also reduces the need to frequentlyTop-up the cooling system.

    Paris


    QUOTE=Wildebeest;1054455]Paris,
    Yes on all three comments although No 1, the raising of the boiling pressure shouldn't be necessary if the system is in good nick.

    It was written somewhere that the 404/504 systems didn't rely on pressure, the low 4lb/" cap designed purely to contain the coolant. Anyone?
    [/QUOTE]

    With the later 13lb caps I've experienced failure of the heater cores on both 404s and 504s.

    The compressed liner engines (1600 and 1800) don't like the 13lb caps either.

    I think the 7lb cap is probably a good compromise.

    I've always suggested that a cross flow radiator be fitted if any engine upgrade is done. In a 504 a VT Holden radiator will fit with some changes to hoses and mounts.

    For 404s the 505 SR or GR radiator is the go.

  15. #15
    VIP Sponsor
    Join Date
    Nov 2010
    Location
    melbourne Australia
    Posts
    74

    Default

    Agreed Rob, 13lbs does risk other "Weak" components, hence I have typically opted for 7psi with no problems.

    Paris

    With the later 13lb caps I've experienced failure of the heater cores on both 404s and 504s.

    The compressed liner engines (1600 and 1800) don't like the 13lb caps either.

    I think the 7lb cap is probably a good compromise.

    I've always suggested that a cross flow radiator be fitted if any engine upgrade is done. In a 504 a VT Holden radiator will fit with some changes to hoses and mounts.

    For 404s the 505 SR or GR radiator is the go.[/QUOTE]

  16. #16
    Fellow Frogger!
    Join Date
    Sep 2002
    Location
    Our most Southern Member (Tas)
    Posts
    277

    Default

    Out of curiosity....
    if you fit an SR system to a 504 with the SR recovery bottle....what is the pressure of the plastic screw on cap of the recovery bottle ?
    .....and assuming they are 13lb.....can you buy a 7lb one ?
    Bob

  17. #17
    1000+ Posts Wildebeest's Avatar
    Join Date
    Oct 2004
    Location
    Perth Western Australia
    Posts
    2,694

    Default

    Bob,
    Fit an unpressurised or vented cap to the bottle. Then a normal recovery 4lb cap to the radiator.
    Although I understand that the 505 etc radiators are capless. A trip down to your radiator guy will fix this.

  18. #18
    1000+ Posts robmac's Avatar
    Join Date
    Nov 2004
    Location
    Melbourne / Caulfield
    Posts
    19,211

    Default

    Many moons ago we had the problem of no radiator cap on my bro's Peugeot special.

    The answer was to silver solder a cap neck into a piece of brass pipe and fit it to the top hose.

    This seemed the best solution a standard water pump, cap at the highest point and a standard radiator.

  19. #19
    1000+ Posts
    Join Date
    Dec 2003
    Location
    anywhere
    Posts
    2,012

    Default

    The 504 wih the standard Australian radiator could and did operate in the hottest conditions without problem. The car was not designed with airconditioning in mind and fitting an airconditioner usually led to overheating problems. Peugeot were sensitive to the problem of the bottom seals and so used no additive in the coolant until 1975. The cars were only filled with water. This led to two problems. The 504 was particularly prone to cylinder head corrosion. There was no provision in the service book for radiator flushing which should have been done annually. In my experience a 504 would begin to overheat after 4 years from new. All these questions of coolant and corrosion were aired very publicly in a consumer action against Peugeot in the U.K. courts in 1977.

  20. #20
    1000+ Posts Peter Chisholm's Avatar
    Join Date
    Aug 2004
    Location
    SWOTR
    Posts
    3,634

    Default

    The only time I can recall any of my 504s getting tool hot was when either the radiator was blocked or something was leaking - water pump, welsh plug, head gasket, etc.

    Maybe it was due to my thoroughly flushing the cooling system each year. This always included removing the radiator and shaking it around while running the garden hose through it.

    Until later years, I never used anything other than tap water and somehow didn't have much head corrosion.

    Only two of my 504s had aircon but I never used it as neither of them worked and I couldn't be bothered getting it fixed.

  21. #21
    1000+ Posts
    Join Date
    Dec 2003
    Location
    anywhere
    Posts
    2,012

    Default

    Head corrosion was probably from using hard water although Bruce Tayler had a theory about the electric current from the fan clutch. Towns that use bore water were deadly. The thing that used to clog were the heaters.

Thread Information

Users Browsing this Thread

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

Posting Permissions

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