No water getting to motor

[Sabaka454]

Hi everyone I am knew here. My buddy has a 1986 Dynasty Cuddy with a 3.0L Mercruiser. I am an automechanic not a boat mechanic so anyway he cracked the cylinder head. I got him a new head and put it on. Adjusted the valves - runs great only problem is no water gets to the motor. So he replaced the impeller pump in the outdrive and still no water gets to the engine. Are we missing something here? There is no restriction in the hose to the waterneck and we even put the prop in a tub of water. The engine's waterpump is only to circulate the water correct? Any help would be great. thanks a lot

 

[Bondo]

Re: No water getting to motor

Is it Clear from the impellerpump housing to the Pickup on the outdrive,..??

Is the Propshaft Turning,..??

Did you Backflush from the T-Stat housing Back to the Impellerpump housing,..??

 

[Coors]

Re: No water getting to motor

You did have water going to the drive at all times?

 

[milkyway]

Re: No water getting to motor

When engine is off and you turn the faucet on, the excess water will come out in the back, behind the outdrive. Then it means that the impeller is working.

If you want to be sure about the impeller, disconnect the water hose at the end of the thermostat - that hose coming from the outdrive- turn on the faucet, and run the engine briefly. Better connect another garden hose to the thermostat to protect the water pump while you're doing this. You should have sufficient water flow at this end of the hose.

If that?s ok, then check the thermostat. If the thermostat is broke, water will not get in the engine.

 

[Haut Medoc]

Re: No water getting to motor

When engine is off and you turn the faucet on, the excess water will come out in the back, behind the outdrive. Then it means that the impeller is working.

If you want to be sure about the impeller, disconnect the water hose at the end of the thermostat - that hose coming from the outdrive- turn on the faucet, and run the engine briefly. Better connect another garden hose to the thermostat to protect the water pump while you're doing this. You should have sufficient water flow at this end of the hose.

If that?s ok, then check the thermostat. If the thermostat is broke, water will not get in the engine.

You will (should) still get some water to the risers through the bypass.....
Welcome to iboats, btw.....

 

[Sabaka454]

Re: No water getting to motor

Thanks for the welcome and the replies! Well he brought the boat over my house tonight so tomorrow I will look at it better. When you start the engine and it is just idling the prop isn't turning what causes the water to be drawn into the engine? Is it the output rotating on the flywheel side of the engine turning the pump? Forgive the stupidity. I am going to look at it better tomorrow and should be a little more educated when I study it.

 

[Sabaka454]

Re: No water getting to motor

ok well there must be a problem with the water pump in the drive. Is replacing this a big deal?

 

[hoot]

Re: No water getting to motor

sabaka, the pump in the foot turns when the motor is running along with the drive shaft and several gears. the prop doesn't turn unless it is kicked into gear. i would suggest that your friend get a manual along with some muffs to attach a water hose to the foot. the vents on the bottom of the foot are where the water enters. don't run the motor without water supplied to these vents on the foot, you will burn up the pump impeller real quick. read thru the postings here and search for the topic, lots of good info.

 

[Coors]

Re: No water getting to motor

"even put the foot in a tub" Did you ever run it with no muffs, or water?

 

[Sabaka454]

Re: No water getting to motor

He may have I don't know. I just got it all apart and the waterpump is melted. The housing was melted and the impeller was melted. So I took my garden hose and popped the hose off of the waterneck and put full water pressure in and it didn't flow out with the same pressure. Restriction? Then I pointed the hose outside the boat and pumped water from my garden hose in the hole where the outdrive goes and it came out even weaker. Do you think this is the problem causing the impeller to melt?

 

[Coors]

Re: No water getting to motor

Yep, started up with no muffs.
Pull the thermostat, and back flush, after removing trashed impeller.

 

[Coors]

Re: No water getting to motor

Running with no water trashed it, and filled any restriction with impeller parts.
Back flush from thermostat down.(pull it); check the power steering cooler.
Try that, and if still bad, pull the risers and check for pieces of impeller...
Never run one dry, been there...

 

[Coors]

Re: No water getting to motor

delete

 

[Sabaka454]

Re: No water getting to motor

thanks! Is it ok to run it with the foot submerged in a tub of water instead? The muffs leak like crazy

 

[hoot]

Re: No water getting to motor

i don't think a tub is the way to go. muffs leak some. cut the flow down. merc makes a repair kit that includes the impeller with housing and gaskets, bout 50.00. be sure to get the vanes bent in the correct direction. this might help, http://www.mercstuff.com/waterpumpinst.htm. be sure the oil seal oring stays on.