cooling problem, good impeller? 4.3gl

brunolund

Chief Petty Officer
Joined
Jan 26, 2008
Messages
417
so I'm helping a buddy fix his boat. it is a 2000 4.3 gl serial number 4012049665
anyway , boat was fine all last year. first run this year on muffs was all good. put it in water and overheated slightly. no known damage. pulled impeller, it looks great. checked it on muffs again it worked fine. checked in lake no water. pulled hose from out drive off pump, I can suck water by mouth from hose. put hose back on, nothing. pulled hose from pump to thermostat and sucked while running engine. got water then pump took over and continued to pump.
pump itself looks fine. is there something I'm missing or is the problem somewhere in the pump not being able to draught water. hose connections were undone and redone many time in troubleshooting this so I don't think an air leak exists there.
also can someone tell me what a new complete pump is worth, and possibly a part number?
looking for ideas as to what's wrong please.
 

brunolund

Chief Petty Officer
Joined
Jan 26, 2008
Messages
417
Re: cooling problem, good impeller? 4.3gl

sorry impeller was changed at beginning of last year. and usually done every two years to prevent this crap.
 

Don S

Honorary Moderator Emeritus
Joined
Aug 31, 2004
Messages
62,321
Re: cooling problem, good impeller? 4.3gl

If the pump is sucking air from either the seal on the pump housing, pump shaft, or the inlet hose, it won't pull water. It might if you prime it, but if it has a choice between air or water, it will pull air every time. It's easier.
 

brunolund

Chief Petty Officer
Joined
Jan 26, 2008
Messages
417
Re: cooling problem, good impeller? 4.3gl

tried to check that. pressurized with garden hose, no visible water leaks. tried sucking by mouth and could not detect air leak. did that on both intake hose at pump, and outlet hose at thermostat. was able to draw water by mouth , so I don't think it's an air leak. just found out he also tried new impeller from Volvo dealer this year after original problem, but did not fix issue. what to do next?
 

vwbugman69

Petty Officer 2nd Class
Joined
Jul 11, 2011
Messages
116
Re: cooling problem, good impeller? 4.3gl

sorry impeller was changed at beginning of last year. and usually done every two years to prevent this crap.

Was a new oring used when the impeller was changed? The old one was removed?
 
Top