Oil riser head scratcher

[turbohunter]

I may be making a problem where there is none so I'll throw it out to you guys.
My mustang engine is a C scratch, date code 8H27.
I'm oiling through the push rods so I want to plug the risers off of the cam journals to the heads.
Ok no big deal just put a plug below deck height and move on, right?
Here's my problem. My truck engine has had a small riser leak since it was rebuilt, which is no big deal it just turns the cooling water grey and taught me a lesson. Now I'm really leery about oil gallery cracks and I don't want a problem with my mustang that I've been working so long on.
Question
Is there a way to block the cam journal to head gallery at the bottom behind the cam bearing without interrupting the oil flow to the mains?

[blykins]

On a 427 block, you can clock the cam bearing to block off the feeds.  On a 390/428, since the block is grooved behind the bearing, it's going to hard to block it there.  Just plug the deck, or plug the feed in the head. 

[turbohunter]

Yeah I get that, but it doesn't address that there is still oil pressure in the oil gallery which could bleed into the water jacket IF there is a crack.
This block has sleeves already in the risers which makes me a bit uneasy.

[Heo]

If i remember correctly the diameter of the riser is smaller
the first inch or so behind the bearing if you make a plug
with the smaller dia At the end and bigger dia the rest
loose fitting smear it with epoxy and drive it in from the deck
I think that will solve it

[turbohunter]

You are correct about the taper and I was thinking of the same thing.
So question.
Let's say you do that. What epoxy will withstand the torture of heating and cooling cycles without flaking? Is there a problem with different materials expanding at different rates do to heat cycles and creating cracks?
I was even thinking, why not just use JB weld and plug the whole riser.
Seems pretty redneck but........

[blykins]

I'm sorry, I misunderstood the question.

If it's sleeved, I think that's about all you're gonna be able to do.  I'd personally be leery about putting any epoxy inside, if it flakes off it will be in the main bearing oil path.

[turbohunter]

Thanks Brent
I'm prolly overthinking as I tend to do these days.