Re: 65 horse mercury help please!
A '63 "650" doesn't have a telltale fitting or hose. The water exits out of a passage in the exhaust manifold, thru the base of the powerhead, and thru another passage in the lower cowling.
The discharge hole is located on the Port side towards the rear, if you look up to the bottom side of the lower cowling you should see it.
You may be able to clear the hole with a puff of high-pressure air, or some fine wire. Very often, especially on an older motor, the passage in the exhaust manifold becomes plugged with silt/debris and the only way to fix that is to pull the powerhead, remove exhaust manifold cover/plate and clean out. A lot of work for a telltale!
You could retro-fit with a 1/8"-NPT 90-deg fitting at the top of the block, and adapt a newer motor's discharge fitting to your lower cowl. This would normally discharge to the Stbd side at the rear side of the lower cowling. You just have to be careful where you drill your hole, so as not to drill into the exhaust manifold section. You may be lucky enough to already have a tapped hole at the top, with a plug in it, you'd have to remove the top cowl/recoil assy to check that out.
As long as you have mixed water/exhaust coming out of your exhaust relief ports, you're OK. Another way to check water circulation, if you're on a flusher, is to check temperature of the water discharging from the prop. If it's warm, it's circulating thru the motor.
Last tip, feel the exhaust manifold cover, which should be cool to the touch or lukewarm at most after a hard run.
Last thought, if you don't know when the impeller was replaced, or it's more than a few years old, it's cheap insurance to install a new one.
HTH & Have Fun with your classic Merc............ed
