Volvo penta 170aq cooling question

[Steel84]

I was wondering if anyone can tell me if the two elbow cooling lines that run parallel to each other on the top of the engine should be warm or cold? I have a 1971 170aq volvo penta. The impeller is fine and the engine does draw in water to cool down. The lines that im talking about have a tendency to heat up and cool down after awhile but it seems like they still run too warm. The needle on the temp gauge hovers around the middle and fluctuates when i run the motor. Could this be because of a bad thermostat? If so are they easy to replace? Any help would be greatly appreciated. Thank you
Pat

1971 Thompson 20' Fisherman
170aq/250 drive

[zbnutcase]

T-stat easy to replace, just remove the housing at the front of the head. And hopefully you dont have exhaust manifold issues.

[Steel84]

Thanks. How would I know if i have exhaust manifold issues? Is there something else to look for? Could I run the engine without the thermostat or no?

[captmello]

No, you should run it with a t-stat.

If the exhaust is rusty and corroded it will slow the flow of water and cause overheat. There's not much you can do to fix or prevent that.

'Nutcase just knows those manifolds go for over 2 grand.

I would just change the thermo to start.

If you need a manual, you can download one in the adults only thread, Volvo info page.

Let us know how it goes.