new water pump not working

I

ibanezrg

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help please! 1979 johnson stinger 75hp. I changed the impeller and housing out and i just cant get to pump out the tell tale or into the block. i have tried both ways with ears and in the lake and nothing. i did notice that when i was putting the LU back on the copper pipe the pump connects to seems loose and also if I blow air into the tell tale it sounds like it is leaking about where the copper pipe hooks to the motor. Is there a seal i might need to change at the top of the pipe? and if so is there any advice i could get on this? thanks in advance
 
Texasmark

Texasmark

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Re: new water pump not working

Haven't been in there lately, but you must have that interface sealed because the water pump has to force the water through the powerhead and if the joint leaks you can loose your pressure and have the problem you are having.

So how they do it on that engine I don't know. Might go to a dealer and tell him that you need a seal for the joint where the copper tube joins the powerhead. See what he brings out.

Mark
 
Texasmark

Texasmark

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Re: new water pump not working

One more thing. While you are at your dealers, get another thermostat. I had a serious problem with a '75 70 hp with a frozen shut stat. That engine must not have a (high speed) bypass valve. If it had, I wouldn't have had the problem I had.

Mark
 
1946Zephyr

1946Zephyr

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Re: new water pump not working

Yep, I inherited a motor that had a siezed thermostat once. Unfortunately, as a result, the motor got hot and discolored the head, but at least it ran good when I fixed it.

If you want to check for water leaks in your pick up tube, then you can attach a small rubber hose to it and your water hose. With the water on low, shine a flashlight up inside the leg and see if anything squirts out at any of the joints. You can also remove the thermostat and see if water gets up there without any problem.:cool:
 
I

ibanezrg

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Re: new water pump not working

thanks guys i really appreciate the advice. Is the clymers a good manual or is there a better one out there
 
cougar1985

cougar1985

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Re: new water pump not working

ibanezrg said:
thanks guys i really appreciate the advice. Is the clymers a good manual or is there a better one out there
Click to expand...
proably the worst.factory manual and then seloc.
 
kenmyfam

kenmyfam

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Re: new water pump not working

ibanezrg said:
thanks guys i really appreciate the advice. Is the clymers a good manual or is there a better one out there
Click to expand...

Clymers are only good if you run out of toilet tissue in my opinion.
 
I

ibanezrg

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Re: new water pump not working

ok i did the water hose trick and it is good. i put the hose on the pipe turned it on and water came out the pee spout. so what i am thinking is that i must have a seal missing or messed up somewhere in the pump housing allowing it to lose pressure? does anyone have a diagram on how the pump and housing go to together so I can visually see what i have done wrong?
 
I

ibanezrg

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Re: new water pump not working

ok guys i think i got it please tell me if i am wrong i am very new to this. i think that for whatever reason the o ring on the topof the drive shaft is not the right one and it isnt sealing the drive shaft tube. With the lower unit in i can blow through the tell tale and hear air coming out around the drive shaft. The pump kit i got had 2 different size o rings in it. I used the smaller of the 2 o rings. The problem i am having now is that the larger o ring seems to have a bit larger inner diameter than the smaller one is too big to sit tight on the top of the shaft just below the gear. how can i find out what o ring i need? and thanks again guys
 
bktheking

bktheking

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Re: new water pump not working

Here is a diagram for you, pulled it off the shop.evinrude.com site in case you didn't know about it.


75pump.jpg
 
bktheking

bktheking

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Re: new water pump not working

This may help. Based on my experience, take it or leave it, I've put water pump tubes back into the pump with folded rubber gaskets in the pump housing, like on the 9.9's and they work just fine and I know for a fact it wasn't a "tight" seal. Sure it leaked but it worked, they don't require a 100 PSI of water pressure to travel into the head and out the tell tail. Remove the lower unit again and re examine your work, something here has been missed and sometimes simply removing and reassembling can fix the problem or lead you to discover the problem. I know it sounds stupid and your going to say it can't be anything like that but trust me, been there and done it on multiple motors and there is no rhyme or reason on why it happens. Even if it's not a tight seal you should still get something, getting nothing means something is wrong, tube didn't go back in, keyway for the pump missing even though you think it's there- it may have fallen out and you are spinning nothing instead of the impeller. As I say, if it worked before you changed it then something is missing in the equation, what changed????
 
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ibanezrg

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Re: new water pump not working

well from the looks of this diagram the old drunk guy at the marine shop gave me the wrong pump kit, except this one looks the same as the pump and housing that I took off. What I am guessing is that the kit i got is interchangable but I think I have the wrong O ring for the top of the drive shaft. This boat has been a nightmare since the second time I had it out. I also cant figure out how to use the shop.evinrude site. I go through the prompts but it always seems to go striaght back to the starting page. Thank you that diagram helped alot.
 
I

ibanezrg

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Re: new water pump not working

it looks like kit 18-3389 except with a white pump housing. And also the guy didnt have the O ring set in it he pulled it from a different pump kit and I am betting it wasnt the same kit as the one he sold me.

Thanks you have been a huge help. I found this site looking for a mechanic to take it to. You guys have been a life saver
 
bktheking

bktheking

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Re: new water pump not working

Right part number, sounds like it was an open box affair, i'd be returning it and getting the right parts or getting at least the correct o-ring.
 
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ibanezrg

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Re: new water pump not working

Well no thanks to the guys I fish tournaments with but apparently they have all had problems with the guy I got the pump kit from so I guess I am not going to back out there again. I bought an O ring kit at the parts store a bit ago so Im going to try that. Thanks again and I will let you know the outcome
 
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mikesea

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Re: new water pump not working

FYI,the oring on driveshaft top has nothing to do with the pump.Make sure you have number 59 in your kit,and it seals around the water tube,
 
bktheking

bktheking

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Re: new water pump not working

I think he means the o-ring at the top of the pump , not where it goes into the crank. If he is referring to the o-ring at the top of the shaft where it goes into the powerhead it won't come with the pump kit and has nothing to do with water flow, agreed.


I'm trying not to ask too many questions these days :D
 
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