1991 115 Johnson Exhaust Filler Blocks

[bill_w]

I'm doing some repairs to a 91 115 Johnson. In the course of changing thermostats, I have the exhaust covers off. The exhaust filler blocks are not flush with the rest of the block, as I've been told they should be. Near the bottom of the crankcase, they are recessed as much as about 1/16" Does this mean I have to get the block machined so that everything is flush, or are they alright as is?

Thanks,
Bill

 

[haffiman37]

If blocks not damaged/burned, leave them as is.

 

[bill_w]

The filler blocks are OK, but the thermostats and plastic pressure relief valves were heat damaged.

 

[bill_w]

# 3 cylinder head gasket was leaking, letting combustion gasses into the cooling water. I think this is what caused the thermostat/relief valve damage.