2.4/200 starts and idles like a dream but gets too hot on the muffs

[pcrussell50]

This is a big head scratcher to me... After finally de-salting and cleaning this 2.4/200 I bought last summer, I finally go around to firing up on the muffs an hour or so ago. I got it before it was too late. Everything came out without breaking. Corrosion was starting but had not gotten far.

It took way too long to for water to start coming out the tell tale hose, and it was too hot, and too weak. Scalding hot in fact. I think it was boiling because of steam. For some reason it did not set off the overheat buzzer, which I then tested by grounding it, and it works perfectly.

I'm at a bit of a loss here...

-I got the exact same results bot WITH and WITHOUT thermostats
-the thermostats are used but test fine in a pan of water (but again, even without thermostats, the problem was identical)
-Compression is 120 even on all six
-cranking max timing was spot on when I got it and I confirmed it at 22 BTDC
-idle timing is per manual, at 7 deg ATDC
-with link and sync and WOT and timing set per the manual it idles nicely on the muffs at 700 rpm.
-starts easily, and idles as long as you like (just weak telltale and scalding hot water
-buzzer does not go off, and tests as functional
-The block is one of the last 2.4/200's a late November 1990 build stamp, and the heads are the newer, one-piece style. I

Just left my shop to get my leak down tester.

-So, weak telltale that takes to long to start, and the water is way too hot, scalding, and steam almost like it's boiling

-If something is cracked and allowing combustion gases into the water, is it more likely a head, or the block?

Any ideas before I head back and to the leak down test?

-Peter