water pump rebuild for old '67 Merc 39

[askiopunk4358796652]

After my motor sunk in fresh water I got it running (yea!) but the water pump doesn't seem to be working real well.<br /><br />Where should the tell tale be ? Is it in the very very back part of the upper head unit and points straight down off the v-shaped tip/nose/tail/whatever of the engine? <br /><br />I am getting intermittent water pumping around the head- I took out the little plug and by holding my finger over it and letting go I can get it to flow real good but then it stops. Is this a bad pump???<br /><br />How do you rebuild/replace the pump on this engine- where is it located? <br /><br />Are there different "levels" of kits and if so which one do I need? Do I need to replace the whole thing or just a couple parts?<br /><br />Thanks so much!<br /><br />Joa