9.9 hp Honda 4 stroke waterpump repair

pete s.

Recruit
Joined
Apr 28, 2008
Messages
5
Thanks for your help in advance:

I recently tore apart the lower unit to put in a new impellar because I had no water flow coming out of the pee hole at the back of the engine. The repair went well although the new impellar I received from the local dealer seems too large but indicated that the ends of the fins fold over inside the housing.

So everything is back together, new lower unit oil, etc and I start the engine up and still have no water from the pee hole. I've checked for screen blockages, none.

After the engine ran for about three min and felt hot I shut it down and opened up the thermostat housing and the thermostats was open, still no water through the pee hole. also checked the pee hole for obstructions, none.

there is no water even making it up the hose to the thermostat.

help please, I'm supposed to troll Lake Michigan tomorrow morning and can't figure this out.
 

marcortez

Petty Officer 1st Class
Joined
Mar 21, 2010
Messages
230
Re: 9.9 hp Honda 4 stroke waterpump repair

Odds on you did not reinstall the water pump impeller correctly.

Pull it apart and recheck your install.
Woodruff key in place? Without it.....the impeller won't spin.

Use a little Vaseline to lube the inside of the impeller cup and on the tips of the vanes.

Use a twisting motion while helping along the vanes to get inside the cup.

3 minutes without water is on the edge of disaster....
If no pee stream within a few seconds of starting....something is wrong.

Although my previous motor was a 25 HP Honda....it shot water out the peehole within a couple of seconds.

Make sure your rinse muffs are sealing the water intake ok.
 

pete s.

Recruit
Joined
Apr 28, 2008
Messages
5
Re: 9.9 hp Honda 4 stroke waterpump repair

I greased the inside of the cup and did as you stated by turning the housing on. Key is in place. Is impellar large than the housing diameter? I wonder if a pice of the shattered old impellar is blocking a hose or something?
 

marcortez

Petty Officer 1st Class
Joined
Mar 21, 2010
Messages
230
Re: 9.9 hp Honda 4 stroke waterpump repair

Yes the impeller is larger.....that is why you need to twist and turn it in the cup.
It needs to be somewhat larger for the vanes to "sweep" the inside of the cup to create the pumping action.

No telling about broken pieces of old impeller but you can try this:

I use some heavy (60 lb test) or so monofilament fishing line (or anything that is thin and flexible) to run up the peehole tube as far as you can.

Often times this procedure dislodges a grain of sand or any other object that has made it's way into the water tube.
 

elkhunter338

Master Chief Petty Officer
Joined
Jun 27, 2009
Messages
818
Re: 9.9 hp Honda 4 stroke waterpump repair

I recently had this same problem with a 25hp evinrude, however the water pump was working when I replaced it.
I got the copper tubing from the water pump to the engine installed wrong, it was hard to line up and this was my first time to replace this water pump.
I had to buy a new copper tube and then everything worked fine. I would expect if your water pump is working you should have had water in the engine. I would take the water pump off and try and blow some air in reverse through the system and about 10psi max. If your old water pump came apart it is very possible a piece of rubber is still plugged some where.
 

backyard mechanic

Petty Officer 1st Class
Joined
Jan 6, 2009
Messages
203
Re: 9.9 hp Honda 4 stroke waterpump repair

Thanks for your help in advance:

I recently tore apart the lower unit to put in a new impellar because I had no water flow coming out of the pee hole at the back of the engine. The repair went well although the new impellar I received from the local dealer seems too large but indicated that the ends of the fins fold over inside the housing.

So everything is back together, new lower unit oil, etc and I start the engine up and still have no water from the pee hole. I've checked for screen blockages, none.

After the engine ran for about three min and felt hot I shut it down and opened up the thermostat housing and the thermostats was open, still no water through the pee hole. also checked the pee hole for obstructions, none.

there is no water even making it up the hose to the thermostat.

help please, I'm supposed to troll Lake Michigan tomorrow morning and can't figure this out.

http://www.boats.net/parts/search/Honda/Outboard%20Engine/0/BF9.9AK%20LA%20OUTBOARD%20ENGINE%2C%20JPN%2C%20VIN%23%20BABL-1100001/THERMOSTAT%20%2B%20INLET%20MANIFOLD/parts.html

That link will get you to the inlet of water and the Therm housing. Item #1 is a zinc anode (they have it obsolete now) that caused my 9.9 to plug up just like you are having trouble with. I had a heck of a time getting the pieces out of the water passages but once I did... she purrs like a cool kitty.
 
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