Water pump HELP needed

ok so my dad and i just bought the boat and we are replacing the water pump on a 1994 150 johnson outboard. first of all bought the waterpump kit 18-3392 we put everything in bolted the lower unit back up and the water is coming out in places im not sure it should. within a minute of the engine running (while on ears) temp continued to rise fast it doesn't seem the water is making it up to keep engine cool. im not sure if we missed something when we reassembled the water pump housing and impeller. we did have to o-rings left we thought maybe they were extra. when we took of the old water pump we used that to guide us on the the parts for the new water pump. we have put the lower unit on and off 4 times now with no luck. any ideas suggestions on what to look for? we doubled checked gasket around the housing it seemed to be fine (not pinched).

Re: Water pump HELP needed

Is your tell-tale squirting a strong stream? The tell-tale is an indicator of pump pressure. You might have thermostat problems.

Re: Water pump HELP needed

Things to check if overheating after pump is rebuilt:
a) pump not assembled correctly
b) you missed the pump outlet with the water tube
c) the grommet in the pump outlet got folded over during final assembly
d) incorrect parts used
e) pump body not well sealed to wear plate
f) pump housing or wear plate scored (if complete kit not installed)
g) pump air bleed hole plugged
h) water not deep enough for the pump to do its thing
i) debris stuck in water passages
j) stuck thermostat or vernitherm
k) key missing or incorrect
l) you went cheap and installed only an impeller, rather than a complete OEM kit
m) diverters missing or incorrectly installed
n) pump rotates clockwise looking from the top

The vanes make no difference ... if you install them incorrectly oriented, they will flip to the correct position upon rotation.

There's likely on O ring on the top end of the drive shaft to keep water out of the splined joint. The splines on the driveshaft need to be coated with grease, but NOT the top of the drive shaft.

Water will be coming out of all the drain holes holes in the LU and midsection. Completely normal.

Re: Water pump HELP needed

form wilde1j's post, "b" is a very common error. (did it once.....and only once!:facepalm: ....ruining a motor at 14 years old, and having to row to fish.....sticks with ya! lol)

Re: Water pump HELP needed

well we fixed it finally ... missed an o ring on the top inside the housing...it was a complete oem kit that we bought took the boat out for the first time tonight and it won't plane. full throttle runs at 2400 rpms????? is it possible we didn't put the shift rod and linkage back together correctly? it seems as though the engine doens't really engage til the throttle is 3/4 of the way down before the boat starts to move. i'm not sure how to explain it but almost like theres alot of play in the shifter but the engine seems to go? also is there a cap on rpms while in reverse? going in forward rpms were topped at 2400 while in the water but reverse seemed to rev alot higher like 3800 rpms?

Re: Water pump HELP needed

If the throttle plates open all the way, you may need to clean and rebuild the carbs following OEM shop manual procedures.

Re: Water pump HELP needed

that crossed our minds as well.... going to fiddle with it now, we will be checking the throttle plates for sure....thank you!!!!!!


renee

Re: Water pump HELP needed

motors tend to cavitate in reverse, which will let the motor rev a bit more. ( cavitation is hard on equipment)