Exhaust smoke in the water jackets....?

[joezek]

I just installed an old looper 140, finalized the wring and did a quick test fire. The thermostats are out, on order, so when I ran it (for 5 seconds) I saw smoke coming out of the thermostat housings.... Is this normal, exhaust coming up through the lower unit maybe? I'm worried maybe it needs a head gasket or some other connection between the water and exhaust is leaking.

 

[racerone]

I would say that is normal.

 

[joezek]

Good I hope so, only other issue is that it wouldn't shut off, which is why it ran for more than 2 seconds. I'm guessing I'm not getting a ground to the ignition to cut it off. The previous owner was having same problem.

 

[F_R]

If everything were assembled, the water leaving the thermostats would be discharged into the exhaust. So yes there is a pathway between the thermostat housing and exhaust area.

 

[joezek]

Ok perfect, thanks for the info. I have the lower unit off while I'm waiting for the new water pump kit, I sprayed shop air into the tube that connects the water pump to the block. When I do that, almost all the air is pumping directly into the exhaust outlet and I don't feel any air coming from the **** tube.

Also noticed the water pump doesn't even come close to fitting snug onto that inlet tube, it's probably losing 80-90% and spraying it all into the inside of the case. When I shut the engine down it will drain for 5-10 min out of that case because there's so much water in it. I'm assuming there was supposed to be a seal to connect the pump to the tube and it was missing