Water Pump Won't Prime 1991 90 HP Evinrude

[pdmoney]

I have a question maybe someone could answer. I've been working on Evinrudes for 30 years.. Never had this issue. its a 1991 90HP.. Did T-stats, water pump, and head gaskets. I cannot figure out for the life of me why this water pump wont prime and pump water. It runs and pumps a little bit on a hose but if you put it in a barrel, covered all the way up past the split, it will not pump! It pumps fine if you run it in the barrel and earmuffs on, even if you take the muffs off while its running in the barrel but not on restart when taking earmuffs off in the barrel... What could possibly cause this? Checked the pump 2 times now.. I'm 99.9999% sure its in correctly. It aint my first rodeo... If you take the hoses off to the T-Stats and run a hose up the water tube it flows freely. Deflectors are OK in the heads/Block. Dont see any cracks anywhere I can see.. Only thought was a cracked water tube.. Going to check that with an inspection cam tomorrow... I'm baffled...

 

[tphoyt]

As you say it’s not your first rodeo so sorry for the questions but.
As you say cracked or rotten water tube, worn out cup, bad grommet, missing key, wrong impeller? Just some thoughts.
Best

 

[pdmoney]

As you say it’s not your first rodeo so sorry for the questions but.
As you say cracked or rotten water tube, worn out cup, bad grommet, missing key, wrong impeller? Just some thoughts.
Best

Thanks for the feedback.. It's an all new (Aftermarket) Pump kit. Complete with housing, etc. Checked it was installed properly twice now. Key is good. Doesnt look like it's just spinning the impeller housing or something stupid like that. I keep thinking its GOT TO BE a simple fix I am overlooking somehow.. Will get to it this weekend again. Curious to see what I can find with the inspection camera.. It's so baffling because I have done hundreds of these pumps and never seen anything like this....

 

[racerone]

I like to use factory kits.-----I don't trust stuff made by the ----hooflungdung -----Aftermarket people.-----So install factory kit and test run.

 

[tphoyt]

Heard a story once about a new housing that was installed that only had a small hole in the outlet portion of it. It was either a bad casting or milling job which ever they did but there wasn’t a big enough port for water to flow. Not saying thats your problem but if you have it apart agin take a peek.

 

[pdmoney]

I like to use factory kits.-----I don't trust stuff made by the ----hooflungdung -----Aftermarket people.-----So install factory kit and test run.

Yes, I have heard that too.. I've never had an issue with aftermarket stuff.. But I am going to check everything again when it comes apart

 

[pdmoney]

Heard a story once about a new housing that was installed that only had a small hole in the outlet portion of it. It was either a bad casting or milling job which ever they did but there wasn’t a big enough port for water to flow. Not saying thats your problem but if you have it apart agin take a peek.

Anything is possible.. I really need to take the ENTIRE thing apart and start from scratch.. The first time it was put in was by a friend who has experience doing them BUT I didnt strip it down to bare bones and start over so I know its a good install. Its gotta be something simple!!

 

[racerone]

Left the water tube seal out of the pump housing ?----Buckled the water tube on install , too short now ?

 

[pdmoney]

Left the water tube seal out of the pump housing ?----Buckled the water tube on install , too short now ?

The seal is in there.. Last time I put the LU on I am 100% sure the water tube went in to the pump housing.. BUT, the friend who put it on earlier this year by himself says he may have heard a "bad noise" when he installed the LU the first time this year. I'm dying to get the camera up there this weekend... Maybe we'll find something with that damn water tube.. (I'm hoping)

 

[v35pilot]

Heard a story once about a new housing that was installed that only had a small hole in the outlet portion of it. It was either a bad casting or milling job which ever they did but there wasn’t a big enough port for water to flow. Not saying thats your problem but if you have it apart agin take a peek.

Inside the water pump housing there is a small groove that connects the impeller area with the outlet hole. If that get clogged with sealant while assembling the steel parts inside the housing, the pump will not prime while in a non-pressurized water environment.

 

[tphoyt]

I’m curious what you found out?