Hello all,

I have an '86 bronco with a 351. Coolant started leaking out of the back bolt on the valve cover just above the exh. manifold. on the passenger side. I tightened the valve cover bolts and the leak stopped.

Is this normal? Is this bolt hole open to the coolant passage in the head?

I have a feeling that I have a head gasket leaking and the coolant is able to make it's way up to the bolt hole.

Any information will be appreciated.

Thanks,

Gary

 

Your bolt holes shouldn't be seeping coolant.
Oil i could understand, but under no circumstances should coolant seep from there.
It sounds to me that you've gotten coolant into your oil and its pumped up through the oil passages into the heads.. so it was seeping out there. i wouldn't run the engine and i would start looking into a rebuild or replace of the engine.

 

That is the first thing I thought. I chacked the oil for the presence of coolant and there isn't any.

Gary

 

I know nothing about these heads. (or most ford heads for that matter)

however Chevrolet had 202 heads in the 60's that did had a valve cover bolt hole that extended into the coolant passage, and it gave me the exact type of scare that you are experiencing. Once I was aware of this, I used silicone on the bolt, and tightened it down. Problem solved.

Obviously this might not be your problem, but I can see where it is possible.

Drew

 

As far as I know, all the early heads had blind holes for the valve covers. If you take out the bolt, does coolant came out? I would take a small wire and probe the hole.

 

IT sounds to me like you may have a crack or rust-through to a coolant passage. I've messed around with more than my fair share of small block heads and I've never seen this before.

Batman