C113 head coolant leak

[mbrady.glide]

Has anyone had issues with coolant leaking from the manifold studs on the #4 cylinder exhaust port on a C113 engine? After rebuilding my A engine, and about an hour and a half of run time in 15 to 20 minute intervals I have a coolant leak from the aforementioned studs.

The block and head were hot tanked and magnafluxed prior to rebuild, with nothing abnormal mentioned by the machine shop.

I haven't had the time to remove the manifold yet, so haven't tracked the source of the coolant yet. But it's only coming from the #4 exhaust port. I'm thinking a crack between the exhaust port and the water passage in the head or the the stud hole in the head. I should have paid more attention during reassembly, but the stud holes are blind right, they don't open into the water passage do they?

 

[CharlesTx]

The studs do extend into the water jacket. You will need to remove the
stud that is leaking and apply a sealant that is resistant to antifreeze.
I had this happen on my super c.

 

[mbrady.glide]

That migh be the best things I've heard all day. So all the manifold studs extend into the water passage then?

 

[CharlesTx]

Can't say they all do. I would seal the ones that show leakage.