Wiped out water pump

**KIRCHNER** · 03-25-2021, 03:30 PM

NEED an educated guess. how long will a v6 merc impeller last at 1500rpm if run dry? ALSO, how deep must the lower be submerged to pump? think its my fault, not happy. pumped fine on the hose when i put it away.

**25two.stroke** · 03-25-2021, 03:37 PM

Do you have pics of how much it got damaged? I assume someone damaged one... and Im assuming its a 2.0/2.4/2.5 impeller not a 3.0/3.2 impeller.
1 min and it would have the tips melted into the housing for sure. Like the point where you need a new housing. 5 min + and the wear plate is starting to melt into the base. 15 seconds is probably the max a 2.0/2.4/2.5 impeller can hold up and still pump fine after.

As far as how deep...well that depends on what kind of lower unit you have!

**KIRCHNER** · 03-25-2021, 04:13 PM

Originally Posted by 25two.stroke

Do you have pics of how much it got damaged? I assume someone damaged one... and Im assuming its a 2.0/2.4/2.5 impeller not a 3.0/3.2 impeller.
1 min and it would have the tips melted into the housing for sure. Like the point where you need a new housing. 5 min + and the wear plate is starting to melt into the base. 15 seconds is probably the max a 2.0/2.4/2.5 impeller can hold up and still pump fine after.

As far as how deep...well that depends on what kind of lower unit you have!

A 2.4 with a bobs. i couldnt up to the cav plate, thats where i went wrong, im thinkin... yeah, what was i thinkin??

**XstreamVking** · 03-25-2021, 04:25 PM

Gotta be over the water pump to prime. It was too hi to do that if at the cav plate. It's prob toast, pull it and see.

**KIRCHNER** · 03-25-2021, 04:42 PM

it was 2'' below plate. ii just started it to see if my hand-me-down tach worked. it worked allright. what a deal! NOT...

**25two.stroke** · 03-25-2021, 05:06 PM

no flusher? you put it in a bucket but it didn't get up to the wp area? You shouldn't ever need water all the way up to the pump but it is ideal...it ads to the life of the impeller. If I could figure out how to post a vid on here I could show you a video of my 2.4 when I first started it after sitting without starting for 5 years. A 5 yr old impeller picked water from1" above the propshaft. It sounds like you had yours deeper than that.

**25two.stroke** · 03-25-2021, 05:08 PM

**KIRCHNER** · 03-25-2021, 06:02 PM

Your saying the pump pulled the water[dead lift] from the bullet up to the pump? no help from hose? i was up to where the side intakes used to be.

**25two.stroke** · 03-25-2021, 06:04 PM

Yeah in that vid it hadn't been primed or anything. Water level was below where the pickups originally were. I didn't think it would pump thats why I didn't really care the water level, but to my surprise the motor started, sucked the water up and pumped fine!

**KIRCHNER** · 03-25-2021, 08:10 PM

Something happened, got to pull it apart. so much for the fresh perfect paint. it had a new impeller also. better luck than i had...

**KIRCHNER** · 03-30-2021, 03:35 PM

i have a new impeller, but it seems i cant just buy a housing? in the kit will there be a seal shaft seal already in housing, or will that be a separate o ring. kit shows a lot of items. why do they show so many gaskets? my wear plate is fine, and gaskets also. lastly. shaft seal under wear plate, should i replace and will kit include that seal.?

**25two.stroke** · 03-30-2021, 04:14 PM

Can't really understand what you are asking. WP kit that had housing comes with the wear plate and gaskets and every oring for I/Os and outboards. Doesn't come with and seals for WP base or shift shaft. No point in buyin all the parts separate so you don't get a wear plate...that will be more than the whole kit.
The WP base comes with the seal in it, I replace the whole thing rather than poppin the seals out. Did it melt the WP base or did that seal fail?

**25two.stroke** · 03-30-2021, 04:38 PM

Yeah the housing shows as just the kit. if you don't need any of the parts I'd send you a housing so you don't have to spend the $50. Did you figure out why it wasn't pumping? If you can't find the problem then its best to change the wear plate and all the gaskets. If you see the problem then just change that piece.

I got a drawer with probably 50 wear plates and hundreds of gaskets, and more in a box at my house just cause they always have that stuff and I rarely use it. I got spare housings too cause I ALWAYS put a whole housing kit in on WP services for hipo customer stuff (unless they request not to have one) whether it looks like you need a housing or not. So I have a few housings that look real essentially brand new but I swapped them out cause the kit came with a new one. WP bases are a different story...

**KIRCHNER** · 03-30-2021, 06:09 PM

i didnt know there was a [base] piece behind wear plate. would that be plastic? seems like all damage, heat was upper area housing,seal liner damage. i better look at base seal closer. i it rare to have to replace base? ive only done impellers, the cause> lack of water, gotta be. located a pump base, but says for non-pre-load driveshafts. will not fit pre-load pin models. 2.0,2.4,2.5. 1986-up. what i have is a hot rod 15'' 2.4 on early ridgeback. non-rachet lower; im assuming this pin would be up under pump base??

**25two.stroke** · 03-30-2021, 06:19 PM

Nah, its common when water pumps overheat they melt the wear plate down into the base around the shaft. Then no matter how many times you change the impeller, wear plates and gaskets the impeller will never seal right around the wear plate cause it can just push it down. Not as big a deal on the fourstrokes and 3.0s that use displacement pumps, but the pressure pumps on I6 / 2.0 / 2.4 / 2.5 are more temperamental.