1963 5.5 hp CD20-C Cooling

[jutila]

Kind folks have answered questions about my big motor, now the kicker! I replaced the water pump, housing and all, but still no water out of the exhaust port in the exhaust housing. Actually, when I first started it, water was spraying out, then it dried up - so to speak. With no water, the engine started getting warm. No apparent clogging in intake. I don't see a thermostat on service manual diagrams. Any ideas on what could be interfering with the water flow?<br />Thanks.

 

[Xcusme]

Re: 1963 5.5 hp CD20-C Cooling

Things to ponder:<br /><br />Is the impeller/driveshaft key in place?? <br /><br />Was the water tube correctly placed in the pump housing upon re-assembly?<br /><br />Are the 'arms' of the impeller turned the right way, in the housing? Tip: use a little dish washing liquid on the impeller, makes it easier to assemble. Soap washes out when you run motor.<br /><br />Did you find any missing 'arms' on the old impeller? (old pieces could have been pushed up the water tube and are blocking the flow).<br /><br />Did you force water up the water supply tube (use a smaller hose on a garden hose) to check for water flow thru the powerhead before re-assembly?<br /><br />If your motor has a seal (grommet) at the top of the water tube, it could have deformed, blocking/restricting the flow, after an overheat.<br /><br />Inspect the impeller closely, did the inner sleeve break loose and 'spin-out'(not turning the 'arms' of the impeller).<br /><br />These are all just guesses at best. Careful observation, some simple tests and the maunal should put things straight.<br /><br />Good Luck and post back with your findings.

 

[jutila]

Re: 1963 5.5 hp CD20-C Cooling

Interesting ideas! I thought I was very careful in assembling the water pump, even lubricating the veins with Vaseline and ensuring that they were folded in the right direction. I could feel tension on the drive shaft when I tried it before reinstalling the lower unit. One has to remove the powerhead on this model to remove the lower unit and get at the water pump (the shift shaft is double nutted at the top. Consequently, I can't run water up through the water supply tube into the power head. The tube was wide open when I looked through it.<br /><br />As far as I could tell, the upper grommet for the intake tube was in good condition - the lower one is new because it came with the pump assembly.<br /><br />What troubles me is that it started pumping water, but then quit. I'm wondering if something could be "floating" in the cooling jacket, creating a blockage. This motor hasn't been in salt water for at least the last 15 years, and by its condition, I think it's only been in freshwater.<br /><br />I'll look forward to more ideas!<br />Thanks.

 

[Chinewalker]

Re: 1963 5.5 hp CD20-C Cooling

Your '63 should have a t-stat on top of the cylinder head - triabgular shaped cover held on by three bolts. Try removing the cover and t-stat, starting the motor and noting any water getting that far. If it does, then you may have a t-stat problem...<br />- Scott