My car was due to be mapped yesterday after a turbo upgrade but then I got a call saying it was leaking water out the exhaust flange on the head.
I haven't seen it myself yet as need to go and collect the car but from the picture I was sent do people think this can be repaired or would I need to look for another head.

I haven't done any of the work so have not seen what it looked like when original manifold was taken off but would of expected the faces to be clean as a new tubular manifold was fitted then problem found when it was run up for the first time.

 

An alloy welder will be able to fix that no problem
is the leak coming from the stud hole or the scabby bit under?
if it is the stud hole it might have been drilled too deep at some point i've done that before

Steve

 

Steve I have no idea as I didn't do the work, it was done by a garage and I haven't seen it with my own eyes yet, just the photo I posted.
Collecting the car Sunday so will investigate once I've got it home.

 

I am suprised that who ever fitted your new tubular manifold did'nt bother to clean anything up or notice how rough it looked by the crack.These days there are specialist alloy welders who should be able to fix it rather than having to source another head I would have thought.

 

Agreed, I'd expect most DIY/home mechanics to have least given that mating surface at least a quick clean
If the leak is from that scabby bit below the thread, i wonder if the person overtightened the stud/nut and thats cracked it...

 

I wasn't very happy when I saw the surface as would of expected it to have been cleaned before new gaskets were fitted and new manifold.
I expect this happens a lot as if it hadn't of leaked coolant I wouldn't have know about it as it would all of been fitted by this point !
Ive found someone that can repair the head, just need to get their home and pull it apart myself and drop the head in to be tested and welded.

And yes the stud stud was snapped doing it up not removing the old manifold !

 

Cleaning mating surfaces is the normal thing that any decent mechanic does always, not a special extra. It is good that you have already found someone who can repair the head as finding another one in good nick would not be easy these days.

 

shonky building imho - not even replaced the rusty core plug

 

While it hasn't been cleaned properly at all there's nothing there I can see that would cause a stud to snap, the raised area appears to be cracked and raised alloy not a lump of gasket
the head should be repairable easy enough I'd of thought

The only scenario I can think of is the thread hole needed tapping out, but instead had a bolt just wound in and it possible picked up on the thread and broke that lump out on tightening it up, if that happened the garage is technically at fault, unless it happened when the stud was removed in which case it's just one of those things

 

The engineer I spoke to said he thinks it's more likely leaking from the core plug from the pictures as he can't see the crack going in far enough to reach the water jacket.
Once I get the car back and take the head off it will be dropped off with the engineer who said they will pressure test it and said they will replace the core plug and weld the flange up and then machine it back to the correct shape and level. He said it's an easy fix but just a shame it's got to be removed to do it.

 

You have obviously been spending quite a lot on the engine so although it's a pain, the cylinder head will be back to how it should be and you won't have to worry about it anymore and you can get everything finished off. Are you getting it fixed locally?

 

Collected the car today but can't see much as manifold and turbo are all fitted so car could be started and moved about.
Discovered that if you pour water in the header tank it runs straight out the hole where the manifold stud should be as it was not put back in. This is with the engine Not running so not being pushed out by the water pump.

Guess im taking the head off this week if I get chance.

 

Could you see if the water was coming from the core plug ?

 

It's quite a common problem with these heads .
my old 3dr head had a stud brake the bottom of the hole very simple fix PTF tape on the stud and it was all good again

 

Have used this on a couple of engines to fix it.

 

I've done this with cylinder head studs on a big cat engine that was letting water up the threads due to the bottom seal cap being cracked, has worked a treat for over 10 years

 

No water coming out of the core plug ! With the stud that snapped being drilled out and a helicoil put in I would say they have drilled in to the water jacket as without the new stud in the hole water runs out the hole when poured in to the header tank.

 

I would prefer a proper fix but might try this as it could fix it but if not the head will need to come off anyway so nothing to loose I guess.

Im guessing ptfe tape doesn't break down when it gets hot then ? As exhaust manifold studs do see a lot of heat !

 

Use this on the stud (good idea to use on all the studs) when fitting them into the head, we use this on all (even brand new) cylinder heads as it also helps the studs from coming undone if you have to take the manifold off. When refitting people forget to tighten the studs up first which is why they pull the threads out of the head.

 

Don't think any amount of sealant or PTFE will fix this bolt hole. Looks like the head will be coming off and the stud hole plug welded and drilled and re-tapped.

 

If they've drilled out a broken stud and drilled to deep it's down to the garage mate !

 

That is exactly what they have done but they are saying the crack was already there and them drilling the stud out has just made it worse so they are not responsible !

Never had any leaks or cracks before they touched it. I know it's down to them but they won't take any responsibility for the damage so have now washed my hands of them as just want it fixed and back on the road.

Once it is repaired I have found someone else who can map it so the company responsible will not see another penny out of me.

 

What’s the garage called mate

 

At this moment in time I'm not going to name who did this or slag them off as I'm hoping they will take responsibility for it but I'm not holding my breath at this time.

 

I would try and repair it with one of the plastic metal products. You have nothing to loose.

 

From the look of the photo that crack is to big for anything simple to fix it. Get the head off and give it to a specialist alloy welder to fix it properly. Ask yourself if you would feel confident with any other option?

 

after finding that crack I don't see anyway of fixing it other than having it alloy plug welded. So once I find some motivation to pull the head off I will do so as not like anywhere is open to get it repaired while I'm stuck at home.

 

The head would need to be removed, you will not be able to weld that stud hole successfully without first removing the core plug and making the stud hole damaged area much larger so you weld to clean aluminium, you cannot just plug weld the hole and re-thread the hole.
Aluminium shrinks after welding so if you do try to weld without removing the core plug it will probably leak (if not already) or fall out after, the core plug hole will need re-machining to an over size as it will no longer be round.
You may be able to drill and tap to a larger size and locktite a blind hole threaded plug with a flange after machining a recess in the gasket face, to accept the flange area then machining again for core plug clearance.
You could always gob it up with one of the liquid metal products, wind a stud in and sell it on ebay as a mint condition YB head

 

Some good information in your thread but I must make a note not to buy any Cosworth parts that you may be selling in the future " In mint condition " !!!

 

Think Steve was being a little sarcastic there he's an engine builder (built mine) and is constantly getting/seeing shite being advertised as mint.........some good info however as normal on a proper fix to the issue.

 

I have repaired some YB heads with similar damage and have seen some lashed repairs, some of these repairs were done on heads purchased on ebay by the car owner thought that was the better (cheaper) option.
I buy to use anything I sell would be repaired and if necessary pressure tested, others just take the money and run

 

I did'nt think you were being serious, i was just joking.

 

From some of the crap sold on ebay, you might have been joking I am not so sure that I was

Steve

 

Once removed the head will be going to a specialist engineering company that do engine parts machining and repair as not taking the risk of, My mate can fix that !
Welding, machining, and pressure testing it afterwards is the only way I can see to have it fixed properly.

I dont intend on doing the job twice

 

I would be interested to know how the company you use, how they recommend the head is repaired.

Thanks

Steve

 

I have no idea what they need to do to repair it as I'm not an engineer. I've sent photos to them of the damage and they said it is repairable and mentioned something about needing to remove the core plug to do the repair so once it's removed and sent off will leave it to an expert to sort it out.

The person ive been speaking to is Lee of Barum engines in Barnstaple Devon.

 

No chance.

it needs done right.

Although it's hard to tell from the photo, a dead ended Timesert type thread repair would likely do it.

A full grind/weld repair....would be a LOT of work.

 

I agree it needs a correctly engineered repair.
But using a product or at least speaking to the companies that make them for advice may allow the permanent repair to be scheduled until the UK is open or the car unused during the winter months.
Belzona would be who I would speak too knowing they specialise in emergency repairs in petro chemical manufacturing. ( not going to Halfords and guessing what may work)
I’m not convinced a timesert would seal but I have no experience of them in a similar application but again it would be worth a try if could be done in situation to delay the permanent repair.
All immaterial as I think the OP is going for a permanent repair now.

 

You are doing the right thing, forget all these "quick fix"solutions and get it done properly by specialists in head repairs who have the knowledge and expertise for a permanent repair.

 

It was always the intention to have a permanent repair but would of been nice if I could of done a temporary repair so I could get the car usable instead of being off the road through the summer months when I want to use it.