1965 6hp not pumping water.

Thompsoncustom

Petty Officer 3rd Class
Joined
Aug 22, 2015
Messages
79
I was out last night and my Johnson 6hp started acting up and wouldn't get above idle so I shut it off and just used the trolling motor to get back to the dock.

Today I blow out the high speed jet and cleaned the fuel filter thinking it was a fuel issue. So I put it in a bucket and it started up and ran fine but I noticed there was Zero water coming out the exhaust so it must have been over heating.

Im new to outboards but I got the lower unit pulled apart and the rubber impeller out thinking the water pump must be destroyed but the impeller looks fine to me.

So my question is now what? Where do I go from here? I'm guessing its full of sand somewhere but not sure how to go about cleaning it out. I can pop stuff apart and take pictures if that would help. Thanks
 

OptsyEagle

Lieutenant
Joined
Sep 13, 2006
Messages
1,356
Are you sure the lower unit was submerged enough into the water to prime the pump? The water level needs to be above the level of the where the impeller sits in the motor.
 

F_R

Supreme Mariner
Joined
Jul 7, 2006
Messages
28,195
Get it out of that bucket and back on the boat, on the lake. Then you will be able to tell if it is working or not. It wasn't designed to run in a bucket. Old saying goes if it ain't broke, don't fix it.
 

Thompsoncustom

Petty Officer 3rd Class
Joined
Aug 22, 2015
Messages
79
Sorry I forgot to mention that I had it in the river last night and still the same thing, starts great but pumps Zero water so I shut it down after about 20 secs.
 

lindy46

Captain
Joined
Nov 27, 2008
Messages
3,886
Check to make sure you put it back together properly. Drive pin for impeller in place and engaging impeller? Water tube in the grommets (both upper and lower)?
 

Fleetwin

Lieutenant Junior Grade
Joined
Nov 23, 2011
Messages
1,141
Check to make sure you put it back together properly. Drive pin for impeller in place and engaging impeller? Water tube in the grommets (both upper and lower)?


Yup, check those.
 

Thompsoncustom

Petty Officer 3rd Class
Joined
Aug 22, 2015
Messages
79
Alright pulled it back apart and this is where i'm at, Engine doesn't seem to be cogged at all I popped the cover on the top of the motor off that give access to some water ports and water will flow out the exhaust and the pick up tube right where is connects to the water pump.

Pulled the pump apart and the key was in the impeller groove, moved the plate under the impeller up and back flushed there and that looks to be all clear. So I put the lower in a bucket off water with the top of the impeller housing sticking right above the water and tooked the drive shaft to my cordless drill and ran it on high clockwise. No water is coming out the top of the housing not sure if thats a good test or not, or if air in the top of the housing would cause any issues.
 
Last edited:

Tim Frank

Vice Admiral
Joined
Jul 29, 2008
Messages
5,333
So I put the lower in a bucket off water with the top of the impeller housing sticking right above the water and tooked the drive shaft to my cordless drill and ran it on high clockwise. No water is coming out the top of the housing not sure if thats a good test or not, or if air in the top of the housing would cause any issues.

It's not a good test.
Pump needs to be submerged.
 

Fleetwin

Lieutenant Junior Grade
Joined
Nov 23, 2011
Messages
1,141
It's not a good test.
Pump needs to be submerged.


Yes, it does. At least to get a prime.

Look at your intake screens also. What's behind them?

This is hydraulics 101. Your are sucking air somewhere between the screens and the power head.

Starting from the skeg up:

1. The lower unit is full of crud. And, the passages to the water pump (impeller)
2. The impeller is weak.
3. The tube to the power head is disconnected or is full of crud.
4. The tube to the power head is missing the grommet at the power head, or both ends.
5. The power head is full of crud. It's easiest to pull the exhaust cover (side gasket) to look.


It is one gasket and simple to remove the power head from the leg. That gives you a glimpse at the underside.
 
Last edited:

Thompsoncustom

Petty Officer 3rd Class
Joined
Aug 22, 2015
Messages
79
Put the pump 100% under the water and with the drill on high water is being forced out the top, so it's either fixed or sucking air somewhere because all the passageways are clear.
 

lindy46

Captain
Joined
Nov 27, 2008
Messages
3,886
So now with the lower unit off, hook up a garden hose to the water tube and see if water circulates through the engine.
 
Last edited:

Thompsoncustom

Petty Officer 3rd Class
Joined
Aug 22, 2015
Messages
79
Thanks for all the help guys. After testing the lower in the bucket I hooked it back up and everything works 100% now.
 
Top