1969 Mercury 7.5... Where's my pee hole?!!

[signs65a]

Hi Guys
I have a old but little used '69 Mercury. I bought it 2nd hand (cheap) and finally got it running today..... well sort of!
I could not find any "pee" hole anywhere on this engine.
In the end I rigged up a hose to the "Flush" inlet and water comes out of the middle of the prop, and a small hole on the RHS under the horizontal blade on the skeg. This would be underwater in normal operations.
When I start the motor this way, it doesn't run too long and oils up the plugs. This is understandable as it running stone cold.

If I put it in a drum of water, I still get no other water coming from anywhere. Which leads me to think that the impeller has gone anyway.

I have looked and looked but I cannot see any pee hole at all.

After running the motor in the drum of water for only 3 minutes it starts to get quite hot.I didn't want to risk damage and turned it off.

There doesn't seem to be anyway of accessing the lower part of the gear case, there are no bolts at all.

Is anyone familiar with this model?
Where is the pee hole, or doesn't it have one?
Is the impeller change a big job?

Thanks

 

[Texasmark]

Re: 1969 Mercury 7.5... Where's my pee hole?!!

I had a 7.5 but forget the year. It may have been mid '75 or thereabouts. I don't remember having pee on mine, but yours probably came out before such a thing was invented, as was probably mine....no such thing in those days.

Pee is nothing more than crankcase water that overflows into the area under the powerhead (where the exhaust goes) being diverted to a visable indicator. Merc started the process years ago for good reason and it worked very well. The pee exit was usually a 5/16" rubber tube, maybe a 1/4" on the smaller engines on the Starboard side of the engine, just aft of the shifter and just below the cowl. The location was deliberately chosen so that an operator could easily look back at his engine, left side looking backwards, and if he saw a stream of water he could feel assured that his engine was getting adequate cooling. The higher the engine rpm's the stronger the stream. This was before the days of the warning horn and for the most part thermostats.

With the advent of the thermostat and high speed/rpm pop-off valve and all the other goodies on the larger engines, you couldn't necessarily rely on the pee stream as on some engines it came off the thermostat output and you had to wait for the stat to open before you could determine if you had cooling water or not..........I never liked that design and if I had an engine with it I would modify it to a positive indication (off the exhaust water jacket cooling manifold).

You probably don't have a thermostat on that engine either. I recall that OMC had stats long before Merc and that was one of the reasons I preferred OMC at the time. Merc overcame the requirement for that with their 40,000 volt ignition system (my best guess but probably accurate), feeling I guess that in salt water operation, stats could foul and become unreliable. (SWAG on my part there, but makes sense) and 40,000 volts could fire the worst of plugs/combustion chamber problems....and they were right.

So on yours, get an impeller, or full water pump repair kit and install it. While doing so, check for water flow throughout your engine. Water coming out the prop is exhaust cooling from the block, as is water coming out above it.....that cools the water jacket of the mid section where the exhaust gasses pass. Without cooling in the midsection, the paint would discolor from heatsd..[I guess Phantom Black would just turn to Phantom Brown (grin)].....case in point, look at some 40 give or take hp OMC engines of the late 50's or so which didn't have it and you can clearly see the heat discoloration.....the ones without the extra sound shroud (top of the line). But you can see it on them too, just remove the shroud.

My 2c,

Mark

 

[WOJO 1]

Re: 1969 Mercury 7.5... Where's my pee hole?!!

Just as Texasmark said. Look on the starboard side just under the cowel. My 1968 9.8 is in that area.

 

[turtles11756]

Re: 1969 Mercury 7.5... Where's my pee hole?!!

i have same same exact motor and it does't have a tell- tale water hole.the lower unit drops down much the same as the larger mercs. there is a guide tube on water pump housing so the water tube lines up correct when re-installing after you change impeller .take a good look and slowly bring down lower unit .lower unit must be in same gear as shifter up top or you will have to start over. put in the impeller and watch for the small key on inside of impeller. don't force anything if done right it will go back together easy. CHANGE the impeller !

 

[letsbrealistic]

Re: 1969 Mercury 7.5... Cowl Removal

Re: 1969 Mercury 7.5... Cowl Removal

Hi ,

I have a 1969 7.5 Mercury outboard and I have no idea how to get the top cowling (lid) off...........could someone please help me.

Thanks!
rob

 

[yoyoholic]

Cowling release 1965 7.5.... This cowing release for this motor is at the back of the cowling under and inside the handle. Reach under the handle you will feel a lever on each side. Pull down.