Mk1 golf gti with 2 litre 16v: overheating

Discussion in 'Mk1' started by harryvr6, Dec 9, 2019.

  1. harryvr6 Forum Member

    Joined:
    Jun 13, 2007
    Likes Received:
    31
    Hi everyone,

    Good friend of mine has a lovely mk1 gti, which has had a 2 litre 16v conversion, engine code and spec unknown sadly. All was well bit it is now overheating. The head has been off and has been checked by a garage and all seems ok there.

    It has a top fill radiator which I suspect could be goosed? I'm wondering what is the best top fill rad for this application?

    I think he has tried a new thermostat, its had a new head gasket too, yet it still overheats. The garage have said maybe try a different head gasket asnit is possibly not the correct one which has been replaced(?)

    If anyone has any ideas or suggestions it would be much appreciated

    Thank you
     

    Attached Files:

  2. Tristan

    Tristan Paid Member Paid Member

    Joined:
    Apr 25, 2006
    Likes Received:
    1,205
    Location:
    Southern IRELAND
    Is the top of the rad as high as the head?
    Without knowing about the head gasket and so on, it's hard to be sure.
     
  3. harryvr6 Forum Member

    Joined:
    Jun 13, 2007
    Likes Received:
    31
    Hi Tristan that's a good question, I would have to ask my friend to check that.

    It seems an odd set up to me, the previous owner carried out the conversion and it hasn't caused him any problems until recently. Basically it was left running g outside my house whilst we chatted and suddenly there was a lot of steam and it let go allover the road, coolant everywhere !

    The culprit was a burst bottom hose or so we thought, but it hasn't been right since then really.
    I shall try and get a photo of the bay posted up.

    Many thanks for your help,

    Stew (harryvr6)
     

    Attached Files:

  4. rubjonny

    rubjonny Administrator Staff Member Admin

    Joined:
    Oct 31, 2003
    Likes Received:
    3,298
    Location:
    Bracknell
    topfil rads can be tricky to bleed, pop the top hose off and pour coolant directly into the radiator see if that helps
     
  5. harryvr6 Forum Member

    Joined:
    Jun 13, 2007
    Likes Received:
    31
    Thanks Johnny, I'm wondering what is causing the lack of circulation (I'm assuming that it what is happening?)

    My friend reports that when the car is left running the coolant remains cold?

    Ive suggested it could be the stat, the rad, the water pump isnt leaking and it's not noisy so that must be ok?

    Many thanks for any further help, stew
     
  6. rubjonny

    rubjonny Administrator Staff Member Admin

    Joined:
    Oct 31, 2003
    Likes Received:
    3,298
    Location:
    Bracknell
    are the heater matrix hoses getting hot? make sure the heater valve is open of course. if so then coolant is circulating thru the block at least.

    as I say the topfil rads can be a pain to bleed so you can pop top hose off and if you pour coolant into the rad directly it can help.

    the lower hose on the rad should stay stone cold till temp gauge gets to around 1/2 then it'll warm up as the stat opens, then fan should cut in around 3/4
     
  7. Tristan

    Tristan Paid Member Paid Member

    Joined:
    Apr 25, 2006
    Likes Received:
    1,205
    Location:
    Southern IRELAND
    Is it definitely the proper stat?
     
  8. harryvr6 Forum Member

    Joined:
    Jun 13, 2007
    Likes Received:
    31
    Brill thank you chaps.

    I'm not sure of the origin of the stat Tristan, I did suggest he fitted a brand new known part, I think he has had trouble with the dan too so that needs to be re visited and ticked off the list.

    As far as the gauge goes, I think it is operable at least so I will get him to check the matrix hoses, and the top and bottom hoses too versus the temp gauge readings.

    Johnny when you say check the heater valve is open do you mean the one on the bulkhead? How would you go about checking it please? Or do you mean put the cabin heater on tp make sure it gets warm? Sorry for the dumb questions!

    I shall pass on this valuable info,

    Many thanks again , Stew
     
  9. 2swe Forum Member

    Joined:
    Oct 25, 2019
    Likes Received:
    52
    Location:
    Czech Republic
    what's the coolant pump propeller wheel condition ? the cast iron ones tend to suffer from corrosion or cavitation..
     
  10. rubjonny

    rubjonny Administrator Staff Member Admin

    Joined:
    Oct 31, 2003
    Likes Received:
    3,298
    Location:
    Bracknell
    both :lol: set the heater to hot and make sure the valve on the heater matrix pipe is actually open so coolant can flow thru the matrix :)
     
  11. harryvr6 Forum Member

    Joined:
    Jun 13, 2007
    Likes Received:
    31
    Great thank you again chaps. I have spoken to Chris and he has said the following:

    "When the car is running, water starts getting high in the rad until it pours out of the top, still cold.

    The heater matrix is open and flowing .

    The heated doesnt work, it doesnt get hot. The temperature gauge works ok, it goes through the roof after about 5 minutes if you start it from cold and take the rad cap off, after a few minutes the water rises and pours out "

    I did suggest just simply replacing everything, Including the water pump, at this moment I'm not sure what the condition of the impeller is like for instance.

    I am also of the thinking that the fan switch isnt working too....

    All of the help has been greatly appreciated,
    Many thanks again,

    Stew
     
  12. rubjonny

    rubjonny Administrator Staff Member Admin

    Joined:
    Oct 31, 2003
    Likes Received:
    3,298
    Location:
    Bracknell
    fan switch might have been the cause of the overheat originally, but it wont be affecting anything now.

    try filling the rad from the top hose and follow these tips, if it still tries to overflow try it again but with the cap on:
    https://clubgti.com/forums/index.php?threads/coolant-system-faq.145091/

    feel the hoses, if they get very pressurised and/or coolant becomes dirty then the head gasket has popped
     
  13. harryvr6 Forum Member

    Joined:
    Jun 13, 2007
    Likes Received:
    31
    Hi all, apparently the head is back after being checked, all fitted back up, re tested, it's still spewing water out of the rad cap and the water is still cold? I havent got access to the car but I hear he is close to giving it a viking burial !

    Have a good one everyone, thanks for all the help.
     
  14. Tristan

    Tristan Paid Member Paid Member

    Joined:
    Apr 25, 2006
    Likes Received:
    1,205
    Location:
    Southern IRELAND
    Sounds like it's being pressurised by the compression...
     
  15. GVK

    GVK Paid Member Paid Member

    Joined:
    Oct 23, 2003
    Likes Received:
    691
    Location:
    Lincs.
    Cracked block maybe?
     
  16. harryvr6 Forum Member

    Joined:
    Jun 13, 2007
    Likes Received:
    31
    Hi chaps thanks for the replies again. Very odd isnt it , I hope it's not the block but yes very well could be, and the pressurisation would be plausible too yes.

    I will wait and see what chris ends up doing with this next, wouldnt surprise me if he sells it to be honest.

    Many thanks again,

    Stew
     
    Last edited: Dec 26, 2019
  17. Tristan

    Tristan Paid Member Paid Member

    Joined:
    Apr 25, 2006
    Likes Received:
    1,205
    Location:
    Southern IRELAND
    I had a mates g60 mk1 behaving similarly. It had a header tank, but the top of the rad was about level with the top of the head and the header tank about the same.
    I lifted the header tank up until it almost touched the bonnet and the problem was solved.

    Might be worth looking at the height of the top of the rad vs the head. Top fill rads were usually on the small block cars that didn't have a high engine.

    Another 16v mk1 I helped build had a top fill, but custom made rad, it had to be jammed right up to the very underside of the slam panel to work properly, and was always a bit iffy to bleed the air out of.
     
  18. harryvr6 Forum Member

    Joined:
    Jun 13, 2007
    Likes Received:
    31
    Thanks again Tristan,

    I know this is becoming a real pain now to my mate. To be fair he has been getting stuck in himself on his drive way.

    The latest update is that the water pump has been looked at: the pipe from it has been detached and it seems that when running the water isnt being forced through the hose it just sits there if you get me?

    But the pump.has now been removed and looked fine, turns fine too!.

    Neither of us are in any way mechanics, just big golf fans, frustrated ones!

    Would it be easier to go back to a header tank setup with a suitably sized rad then?

    If space is at a premium which I'm guessing is the case, which oem item is best to use?

    Many thanks again,

    Stew
     

    Attached Files:

  19. Tristan

    Tristan Paid Member Paid Member

    Joined:
    Apr 25, 2006
    Likes Received:
    1,205
    Location:
    Southern IRELAND
    Pump impeller needs to be quite close to the housing to work properly, caught me out on an 8v car. Impeller and pulley definitely tight on the shaft?

    Re fitting a header tank, a standard got mk1 rad and header would be fine, bit of tweaking of pipes .

    If the header tank bracket is gone, I'd fit a mk2/3/4 item. But for test, any header tank, just cable tied in place would do.
     
  20. harryvr6 Forum Member

    Joined:
    Jun 13, 2007
    Likes Received:
    31
    Thanks Tristan, Ive told my mate and hes going to have another look. Currently hes so fed up with it, I think hes going to end up getting rid sadly, hes had over 20+ mk1s over the years and hes said this is the last!
    If only I could afford to have it off him...

    Many thanks again,

    Stew
     

Share This Page

  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice