Cavaciuti@aol.com Posted June 5, 2019 Report Share Posted June 5, 2019 Hi, Back in Jan I bought a GT6 Mk3 with a 2500pi engine (on twin Strombergs), & since found it's got a Vitesse g/box, so a real 'bitsa'. Have stripped & rebuilt engine with new head gasket, but when I fired it up this afternoon there is blue coolant leaking up one of the Cylinder Head studs & through the nut thread. Only 1 stud seems to be leaking - back of engine, drivers side (above the starter motor). Tried re-tightening nut, but it's still leaking. Has anyone seen this before? Struggling to think how it could happen or how to fix, so any advice gratefully received. Cheers, Simon. Link to comment Share on other sites More sharing options...
JohnD Posted June 5, 2019 Report Share Posted June 5, 2019 Pic not clear, but is that a glistening meniscus of leakage on top of the rearmost head nut? Sorry, I just don't believe that anything can leak up the thread. Hang on. Sometimes, head studs will have a vertical slot cut in the thread at one end. This is to ensure that the stud, going down into the blind ending hole in the block does not pressurise. The slot allows air or fluid to escape. Have you installed the studs upside down? John Link to comment Share on other sites More sharing options...
dougbgt6 Posted June 5, 2019 Report Share Posted June 5, 2019 My new studs didn't have a slot, the pressure would at some point have to make it's way up the stud thread, why would they need a slot? Besides which water is getting in at gasket level, not below. If it is coolant you have a gasket leak, sorry. Doug Link to comment Share on other sites More sharing options...
Pete Lewis Posted June 5, 2019 Report Share Posted June 5, 2019 As john says studs should have the slot down the thread to release any oil coolant held down the threads or you can blow the block screwing them into their threaded holes. im not aware any block holes are through to the water jacket as such coolant up the stud and out thought the nut threads has to be a hole in the head leaking into the stud hole or the new gasket is having a problem. is their any history in the cooling head leaks etc. pete Link to comment Share on other sites More sharing options...
Cavaciuti@aol.com Posted June 6, 2019 Author Report Share Posted June 6, 2019 That meniscus on rear-most nut is indeed the leaky stud. Only picked car up in Jan, & started work straight away, so unsure on if it was leaking before. Studs definitely aren't slotted. Was hoping not to have to get head off again, but doesn't take too long so ... Many thanks for the replies - all appreciated. Simon. Link to comment Share on other sites More sharing options...
JohnD Posted June 6, 2019 Report Share Posted June 6, 2019 Done some reading, which I should have done before saying it was impossible, and I'm wrong. Hydraulic fittings typically leak along the threads, so although they leak from thousands of PSI and the coolant pressure may be a few tens, it is possible. But a leak will occur up the outside of the stud, so if the fit between the threads is not as close as that between head top face and nut, or nut and washer, then it might come out of the top. But the coolant has to get to the stud and stud hole, and only an abnormal communication as Pete describes can account for it. If there is a slot in the therads at the top of the stud, then reversing it to correct its position mught be possible, otherwise, it's head off and investigate. JOhn Link to comment Share on other sites More sharing options...
RogerH Posted June 6, 2019 Report Share Posted June 6, 2019 If the studs go into the block (they do) then somewhere the bottoms of the stud must be below the waterline. If there is a crack or corrosion pit going through the block into the stud hole then it will eventually leak. So it could be the bottom of the stud. It could be the head gasket. There is also coolant in the head. So there may be a crack in the head. You could take a chance and use a sealant like K seal to get you through the summer. Or simply take it all apart. Roger Link to comment Share on other sites More sharing options...
dougbgt6 Posted June 6, 2019 Report Share Posted June 6, 2019 10 hours ago, Pete Lewis said: As john says studs should have the slot down the thread to release any oil coolant held down the threads or you can blow the block screwing them into their threaded holes. I've never seen a vertically slotted stud and I've done a few head gaskets, old minis used to eat them! 7 minutes ago, JohnD said: only an abnormal communication as Pete describes can account for it Again old minis, blown head gasket, coolant bubbling up the stud quite common. Doug Link to comment Share on other sites More sharing options...
JohnD Posted June 6, 2019 Report Share Posted June 6, 2019 But this isn't just any old cylinder head leak ... this is a Triumph cylinder head leak. 1 Link to comment Share on other sites More sharing options...
Cavaciuti@aol.com Posted June 6, 2019 Author Report Share Posted June 6, 2019 Guess I was hoping to find a quick fix ... but to quote Madam Guillotine, it's "Off with the Head". Thanks again all. S. Link to comment Share on other sites More sharing options...
Pete Lewis Posted June 6, 2019 Report Share Posted June 6, 2019 HG is the simplest cause, I think the worst is a a bit on the wild side of simple All my triumpf studs are slotted , , bear in mind there is more hydraulic risk whacking them in with powered stud box than a slow twiddle with two nuts, so on production more troubles if the block wash filled the holes but there have been examples of blown block i think on the lost forum where the forces have blown the top face out , as would serious over tightening I think Kseal or Barrs leak would be worth a try, they do work and are not a bodge (we fitted a Barrs to every truck for years to solve any early life seapage) Pete 1 Link to comment Share on other sites More sharing options...
dougbgt6 Posted June 6, 2019 Report Share Posted June 6, 2019 51 minutes ago, JohnD said: But this isn't just any old cylinder head leak ... this is a Triumph cylinder head leak. Reassuringly expensive. Or is that Waitrose? db Link to comment Share on other sites More sharing options...
poppyman Posted June 6, 2019 Report Share Posted June 6, 2019 I had this many years ago on a car (i cant remember what car) and as the customer did not have a lot of money, i took the nut and washer off and put hylomar over the threads nut and washer (loads of it) and the re torqued it and removed excess........ Result? No more leaks and it never leaked again.... Maybe worth a try?? Tony. Link to comment Share on other sites More sharing options...
Badwolf Posted June 6, 2019 Report Share Posted June 6, 2019 41 minutes ago, dougbgt6 said: Reassuringly expensive. Or is that Waitrose? db I think that was Stella (excellent value) Link to comment Share on other sites More sharing options...
dougbgt6 Posted June 6, 2019 Report Share Posted June 6, 2019 Was she now! db Link to comment Share on other sites More sharing options...
GT6M Posted June 6, 2019 Report Share Posted June 6, 2019 nowt unusual here really that stud is near a water jacket hole prob due t,rust or age related wear,n tear, loss of torque ont nut water under pressure has found its way t,the stud. whats worry,n t,me is that that stud could noo be stuck solid in the head cos of the rust on stud an head. If yer no that bothered, loctite the nut an washer in spot if like me worried, then try an take stud oot, see if its free If it comes oot, fine, clean up, re insert and loctite nut an wesher in spot if it wont budge, then ye got probs when heed needs t,come off, as lots of cyl heeds wont come off at all, even hang,n weight oft car on them and some serious wacks with a BFCH !! M Link to comment Share on other sites More sharing options...
Pete Lewis Posted June 7, 2019 Report Share Posted June 7, 2019 I echo Marcus way back I had a mk1 2000saloon jacked the head till car was airbourne and they dont shift Eventually with small gap cut the one stud holding with cornflake packet round a hacksaw blade cut through the remaining stud Off with the head, the stud remains unscrewed with fingers the part in the head needed a sledge hammer to punch it out And the advantage it would never have leaked Ha ?!!!, the head was blown between 3 and 4 Happy days Pete Link to comment Share on other sites More sharing options...
dougbgt6 Posted June 7, 2019 Report Share Posted June 7, 2019 Or, Doug & Pete swinging on a 3 foot breaker bar works! We got all my studs out and no sign of rust. They had just been inserted by a gorilla. I wouldn't reuse, get new. Doug Link to comment Share on other sites More sharing options...
Badwolf Posted June 7, 2019 Report Share Posted June 7, 2019 ...but, is the quality of the steel in the new studs as good as the worn studs that come out. Are you putting in new cr@p in place of worn but probably better metal? These and other similar questions will never be satisfactorily answered and carry on the discussion of 'rubbish new parts'. Link to comment Share on other sites More sharing options...
dougbgt6 Posted June 7, 2019 Report Share Posted June 7, 2019 All you can do is buy from a big name and I don't mean Fleabay! Got mine from Canley, 2 years have passed and the forum will be the first to know should there be a problem. Is that tempting fate? Doug Link to comment Share on other sites More sharing options...
Badwolf Posted June 7, 2019 Report Share Posted June 7, 2019 "I have an electronic ignition system that is 30 years old and still working perfectly" the man said. Two weeks later @@!!!???@@. Yes lets all tempt fate together. Link to comment Share on other sites More sharing options...
dougbgt6 Posted June 7, 2019 Report Share Posted June 7, 2019 I have no chance of winning the big lotto draw tonight, what would I do with all that money? I don't need it! db Link to comment Share on other sites More sharing options...
Colin Lindsay Posted June 7, 2019 Report Share Posted June 7, 2019 I don't see any point in buying a ticket, I never win anyway. Link to comment Share on other sites More sharing options...
poppyman Posted June 7, 2019 Report Share Posted June 7, 2019 No point in winning big money, we would only spend it on a new garage with a ramp...... Oh i forgot you already have one Colin Tony. 1 Link to comment Share on other sites More sharing options...
Badwolf Posted June 7, 2019 Report Share Posted June 7, 2019 Maybe we should all form a syndicate? Link to comment Share on other sites More sharing options...
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