Coolant in oil...cracked block?

[Oldtech]

Just a suggestion. I  am not familiar with the 31 linkage particularly, but a common source of sticking on this era cars is whatever slide mechanism they use for the hand throttle control on the steering wheel.  They wear and stick. sometimes all you need is a dab of grease.

[Mark Shaw]

On 10/17/2022 at 8:07 AM, drovak said:

Mark, where are these freeze plugs you refer to?

Sorry it took so long to answer (Health issues lately).   I had this issue with my 29-27 Buick years ago, but it was a 6 cylinder.  I found this straight 8 photo online showing similar freeze plugs on the manifold side.   

 

If memory serves; the plugs are under a long side plate on the push rod side that requires removal of many machine screws.  That plate prevents plug leakage to be seen and it directs any leakage via the roller lifters into the pan.  

[Mark Shaw]

On 10/17/2022 at 8:07 AM, drovak said:

Mark, where are these freeze plugs you refer to?

Sorry it took so long to answer (Health issues lately).   I had this issue with my 29-27 Buick years ago, but it was a 6 cylinder.  I found this straight 8 photo online showing similar freeze plugs on the manifold side.   

 

If memory serves; the plugs are under a long side plate on the push rod side that requires removal of many machine screws.  That plate prevents plug leakage to be seen and it directs any leakage via the roller lifters into the pan.