Late 70's outboard water pump issue?

[that_guy]

Hi folks,

Yesterday I took my late 70's gamefisher 15hp short shaft outboard out for a spin. I noticed that when I was not in gear that the water pump did not seem to be working, but once I put it in gear it fired right up.  Is this normal? I've only used the motor a few times and never paid attention.

Thanks in advance for any insight you might have on this one...

 

[that_guy]

Maybe you folks need some additional details to generate a response?

It's a model 217-586331.

When I'm at idle there is no water coming out of the pee hole but once I add a little throttle while in gear it starts to run water just fine. Can someone with a mechanical background confirm if it could be a bad seal, impeller or if I just need to not worry?

 

Thanks.

[RebelSS]

Replace the impeller. That should be an every other year thing. They dry up, the "fins" get brittle, crack, break off, or glaze, and do exactly what you are experiencing. Damage results real fast in that instance. If it's older than 4 or 5 years, you're way past due.

[delcecchi]

1 hour ago, RebelSS said:

Replace the impeller. That should be an every other year thing. They dry up, the "fins" get brittle, crack, break off, or glaze, and do exactly what you are experiencing. Damage results real fast in that instance. If it's older than 4 or 5 years, you're way past due.

It is totally not an "every other year thing" in Minnesota at least.  But in this case, there are symptoms that say the impeller is worn and it is time to fix it.  

I have asked multiple dealers about this, both for my Merc 115 and its successor Suzuki.  All have said that it doesn't need to be replaced very often. 

[RebelSS]

Well, MY dealer , who knows I do it myself.and the factory trained mechanic from Johnson/Evinrude that is a friend of mine, said it IS. So does my Johnson engine book.  Reason why they call it preventative maintenance.  Maybe that's why I don't have issues with any of my engines. Seems everyone else does, though. Can't see where Minnesota has anything to do with it. Dirtier water will and can make it fail sooner, from all the dump that is sucked up by the intake, ala Zumbro river. Or, from lack of use. My boat sat for two years inside...and the impeller was hard, and started to glaze, resulting in low flow. Discovered last Fall while they were putting my engine on the dyno for a prop test. That definitely needed replacement, It's sitting on my workbench for proof of what can happen. But, whatever works for ya. I just prefer not to fry my heads when it goes out on an across-the-lake high speed run.

 

• About 
  •  
  •  
  •  
  •  
• Membership 
  •  
  •  
  •  
  •  

  •  
  •  
  •  
  •  
  •  
  •  
  •  
  •  
  •  
• Towing 
  •  
  •  
  •  
  •  
  •  
• Insurance 
  •  
  •  
  •  
  •  

  •  
  •  
  •  
  •  
  •  
• Boat Loans 
  •  
  •  
  •  
  •  
• Boat Graphics 
  •  
  •  
  •  
  •  
  •  
• Resources 
  •  
  •  
  •  
  •  
  •  

  •  
  •  
  •  
  •  

• BoatTECH Articles
• BoatTECH Categories
•  

Replacing a Cooling Pump Impeller

By Don Casey

 

Fresh water (or coolant) is usually circulated through a boat engine by a centrifugal pump, the same type of pump that circulates the coolant in your car's engine. Centrifugal pumps rarely fail, and when they do--indicated by water dripping from a hole in the bottom of the pump--they are simply replaced. But because they are intolerant of foreign matter, centrifugal pumps are not used as raw water pumps.

The raw water side of the cooling system is almost certain to have a rubber-impeller-type pump. Rubber impellers pass twigs and pebbles and small pilchards, but stop the flow of water to them and they shed blades like leaves in an October storm. What could cause the flow stop? An intake blocked with a plastic bag or other debris. An air lock resulting from heeling under sail. A closed seacock.

Checking the exhaust for spray every time you start the engine can sometimes prevent impeller damage--if you react quickly to dry exhaust. But despite your vigilance, sooner or later the raw-water pump will fail, and rarely at an opportune time. To avoid the collateral consequences of pump failure, routine impeller replacement is a good practice. Many boaters replace the impeller annually. How often you should replace yours depends on how much or sometimes how little you run your engine. At least every other year is a good idea

 

Don Casey has been one of the most consulted experts on boat care and upgrades for 30 years, and is one of the BoatUS Magazine's panel of experts. He and his wife cruise aboard their 30-footer part of the year in the eastern Caribbean. His books include Don Casey's Complete Illustrated Sailboat Maintenance Manual, and the recently updated This Old Boat, the bible for do-it-yourself boaters.

.

 

 

 

 

 

[that_guy]

Thanks for your input!  It had sat for two years without being used after it's last service.  I'll track someone down in my area who can service an older outboard.

Any suggestions for the Shoreview area?

[RebelSS]

I can't help ya with the Shoreview area, but for $11 (that's what I show for the impeller kit you need) it's well worth it. Look at your cylinder head paint close too, if it looks "burnt" or discolored, you might want to replace the head gasket too. Hopefully you're OK on that. The kit install is a piece of cake. You'll get new seals with it, too.  Good luck!  Better safe than sorry......

[that_guy]

Can you send the link for the $11 impeller kit?  I can only find them for $30.

Thanks RebelSS

[RebelSS]

That may be right...the one I had looked at was a common impeller for those early years...and looking now, they vary from $11 up to $32. My bad! If you can find the right one, the kit, at that price, I'd go with it.  Sorry about that!!!  

[leech~~]

If you want to give it a go there is some good info here. http://www.leeroysramblings.com/chrysler_force_gamefisher_15.html

Doesn't look to bad really. Good luck either way.