1974 65 HP 3 cyl cooling issues

[cheapthrills]

First, the questions:
1) Does this motor have a thermostat and poppet valve?
2) If so, where are they located? (Seloc manual does not show)
3) I am not getting water out of pee hole. Any other causes to check?
4) Can overheating cause it to miss?
History:
Bought 77 Sportcraft w/ 1974 Merc 3 cyl 65 HP in ATL in June, rebuilt carbs, had it tuned and ran it all summer w/ no problems. Water coming out of pee hole in lake and w/muffs. Moved to Fla in August.
Ran boat for about 4 - 5 hours, idle to cruising speed, just putting around in Black Creek, which is brackish. On way back to boat ramp, ran over a 4 X 4. About 10 minutes later, boat started to miss badly. Noticed fuel leak by bulb in fuel line. Tightened up, but kept seeping. Don't know if fuel bulb caused miss or if motor overheated and started missing. Made it back to ramp and towed boat home. Put muffs on it to flush, but no water out of the pee hole. Pulled lower unit this weekend-impeller looked fine, but replaced entire water pump assy. Put it back together and put muffs on it. Still no water out of pee hole. What else should I check?

 

[Laddies]

Re: 1974 65 HP 3 cyl cooling issues

Your engine does not have a thermostat, you have the telltale or hose running to it plugged. The should be a 1/8th pipe plug on the water jacket cover remove it and start the engine to see if it's pumping.

 

[cheapthrills]

Re: 1974 65 HP 3 cyl cooling issues

Thanks for your quick reply. I will check the hoses and remove the plug tomorrow.

 

[mthieme]

Re: 1974 65 HP 3 cyl cooling issues

Red flag going up here.
Bob - there's a blip on the radar.
Azimuth 5 degrees, range 1 post
Torpedo tube one READY

 

[cheapthrills]

Re: 1974 65 HP 3 cyl cooling issues

Woo Hoo!! I removed the cooling hose off the tattle tale fitting and the other end off the fuel pump housing. I blew through it and it was free of any obstruction. Attached one end of the hose back onto the tattle tale fitting and blew through it from the fuel pump end and it was completely blocked. Removed the tattle tale and cleaned it out completely. Put it all back together, put the muffs on and fired er up!

BAM!! It Peed!!
Now, if I could just figure out why I always assume the worst whenever I face a mechanical problem, I would be a happy camper!!!!

Thanx for the advice again!