waterpump on MerCruiser 470

[Early]

My 84 mercruiser 470 is leaking antifreeze (it is a closed system) from a small "vent hole" behind the water pump. Obviously something is wrong. Anyone know what might be wrong? Does the waterpump need to be replaced or just some seal/part inside?

 

[Backlash]

Re: waterpump on MerCruiser 470

If you're losing coolant out of the weap hole on your water pump, replace the pump. A rebuilt pump is a cheap proposition and the labor involved is minimal.<br />Good luck.

 

[Early]

Re: waterpump on MerCruiser 470

Backlask, I called the local parts place and they told me that there is not a water pump per say. They said that "pump" is connected directly to the cam shaft and that I needed to replace cam seals. Does this sound right? Sounds like one big job.

 

[ODDD1]

Re: waterpump on MerCruiser 470

Early, the coolant circulating pump on these engines is an impeller mounted on the end of the camshaft....there are 2 seals on the camshaft to keep the antifreeze in the cooling system, when they fail antifreeze weeps out of the vent hole....if the vent wasnt there the antifreeze would go in the oil pan, a VERY bad thing.<br />The seals run on a steel shaft, if the antifreeze hasnt been change regularly, or water has been run in it, the shaft corrodes and ruins the seals.<br />To repair you are talkin about removing the balancer and front cover on the engine, is an involved repair.....

 

[Backlash]

Re: waterpump on MerCruiser 470

Sorry Early,<br />I had another "senior moment" thinking of an entirely different setup. Thanks ODDD1 for setting us straight.