Water pump issues

[Jhawk090108]

Not too long ago I posted about my 25 Nissan fouling plugs. I have changed the plugs to the suggested p type plugs but have not had a chance to run them yet. After changing them I started the motor in a barrel and let idle for a few minutes. The motor never did start peeing. I pulled the water pump and it looks to be in pretty good shape and my local mechanic agreed that that was probably not my problem. I blew air back through the hole while the lower unit was off just in case of obstruction and put it back together. Still not peeing. I pulled thermostat And stared engine and there is no water mAking it to the thermostat.
Any advice on where to look next would be great. On a tight budget and can't afford to get this thing worked on right now. Crappie will be biting soon!

thanks

 

[TwoRivers]

Re: Water pump issues

Blocked intake screens?
Just a guess.

 

[Sea Rider]

Re: Water pump issues

Did you secured impeller key on shaft ? connect water pump grommet to water tube when testing removed thmo ? Probably missing key or out of grommet/tube alingment ?

Happy Boating

 

[Jhawk090108]

Re: Water pump issues

Did you secured impeller key on shaft ? connect water pump grommet to water tube when testing removed thmo ? Probably missing key or out of grommet/tube alingment ?

Happy Boating

Screens are clear and the key is definitely in the shaft. I'm fairly certain that the water pipe is connected to the water pump or at least it was when I reassembled. I am not certain about at the top where it joins the motor and I'm not sure how to check either.
I'm not really sure but if the water pipe wasn't connected to either the water pump or the motor itself, wouldn't water be coming out of the hole in the front of the shaft housing? That's why I'm confused. Water pump should be pumping by the looks of it and there is not water coming out of this thing anywhere.

Thanks for the help

 

[Sea Rider]

Re: Water pump issues

Jhawk,

Remove black rubber hose from powerhead, spray a good shot of W40, let soak, with red cannula poke peeing tube back and forth several times the deeper that will go, probably have an internal clog. You could use a plastic tie & wrap of proper width to clean clog too.

If WP grommet is disconnected from water tube will see lots of water exiting through prop & prop housing when using muffs and motor on stand. If clearing peeing hole clog doesn't work out, you'll need to pull leg again and check, probably key fell when assembling impeller and assumed it's there. Rotate impeller CW when sitting housing on impeller. Before assembling back tail, connect a drill machine on upper drive shaft, submerge tail on a water bucket, turn drill on and check if water is exiting upper grommet. If not U have a WP issue.

Happy Boating

 

[TOHATSU GURU]

Re: Water pump issues

Put in a water pump kit and see if that fixes it. Most people cannot distinguish between a marginal set of parts and good parts. IE Wear to the liner and plate.

 

[pvanv]

Re: Water pump issues

Luis does have an OK "shade tree mechanic" way of determining whether you have any pumping at all. But, in all fairness, Elvin is (as usual) correct. The wp kit likely needs to be replaced. 361873220M WATER PUMP REPAIR KIT 25B-40C $46.67

If you are going to turn your own wrenches, you should have a copy of your trusty FSM: 003-21035-1 SERVICE MANUAL, 1 & 2 CYL, 2-STROKE $45.00

As for how the water pipe attaches, see



FWIW, the thermostat will NOT affect the peeing.

 

[Sea Rider]

Re: Water pump issues

Before assembling back tail, connect a drill machine on upper drive shaft, submerge tail on a water bucket, turn drill on and check if water is exiting upper grommet. If not, U have a WP issue.

U have a WP issue means : you have a shot WP. Check firstly rubber peeing hose which exits through pan and powerhead metal tube which protudes through lower powerhead side are 100% clog free before venturing throwing through the drain $100 worth of WP kit + Service Manual.

My shade tree mechanic way of determining trouble does work, it's the first step into WP troubleshooting without any investment. it's a DIY simple and cost free work. Have my doubts about liner and lower plate failure which should be found guilty performing the WP drill test. Have 30 HP horses with 1.5 K metered woked hours with same WP factory delivered and peeing heavenly. That engine surely has low worked hours compared to.

(1)Check both peeing ports are clog free, 2) perform the drill WP test, if found guilty, (3) change complete WP Kit.

Happy Boating