Waterpump seal

pdqford

Cadet
Joined
Oct 28, 2010
Messages
21
I’m installing a new waterpump impeller and seal on my 1981 Chrysler 75 HP triple.
The replacement waterpump to driveshaft seal doesn’t look exactly like the old one.
The new seal has a “garter” spring in the rubber part of the seal.

Should this seal be installed in the waterpump housing with the “garter” spring UP (toward the motor), or DOWN (toward the impeller)?

Thanks in advance for any assistance.
 

pdqford

Cadet
Joined
Oct 28, 2010
Messages
21
If I can ask a follow up question?

When I pulled the lower gear case, a ring and a rubber sleeve fell out of the upper unit.
I think this ring slides over the driveshaft splines and rest on the little ridge just below the splines.
And the rubber sleeve then slides down over the splines and into the ring.

My question is - which way does the rubber sleeve go on?
Should the bulge in the sleeve go toward the splines? Or toward the waterpump?

And the sleeve seems to have some grease inside the bulge.
Should I fill the bulge with a waterpump type grease?

Thanks again for any advice.
 

jerryjerry05

Supreme Mariner
Joined
May 7, 2008
Messages
17,923
It's designed to keep the splines lubed and water out.
The rubber has a ridge, that goes down.
The bulge is so it can flex down as the splines go in the bottom of the crank.
Then marine grease on the splines and then slide the cover over.

A touch of marine grease on the impeller, it's not really needed,
but helps when the cover goes over the vanes.
 

Nordin

Commander
Joined
Jun 12, 2010
Messages
2,428
The rubber boot is not necessary.
Grease the spline and pull the LU every second or third year and grease again.
 

pdqford

Cadet
Joined
Oct 28, 2010
Messages
21
Thanks again for the help. This site is really helpful

Can I ask one more (final?) question?

I ran a tap through the seven holes where the lower unit bolts on to clean them up.
It kind of looks like there was maybe some black silicone or maybe a seal in those threads.
(I assume the lower unit has NEVER been removed before as I have owned the boat for 34 years!)
What is the recommended method for reinstalling the lower unit bolts?
Just slather them up with a thin coat of anti Seize?
Or coat them with RTV when I install them?

Thanks again for your advice.
 

jerryjerry05

Supreme Mariner
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May 7, 2008
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17,923
34 YEARS!!! and using the same impeller!!! WOW!!!

I use marine grease on the bolts and screws that hold the lower unit on.

In salt water Anti-seize becomes Permanent Seize.
 

pdqford

Cadet
Joined
Oct 28, 2010
Messages
21
Just wanted to thank all for their responses. I got this Chrysler back together, finally.
Just don’t have the strength to lift that lower unit up into the motor and get the driveshaft splines lined up.
So here’s how I got it back in: (apparently my iPad takes to big of a picture to upload to this site.) I put the pallet forks on my bucket tractor and strapped the lower unit to the pallet forks and eased the lower unit up into the motor. It still was not easy to get the shift linkage, the driveshaft splines and the water pipe all lined up at the same time!

But we got it back together. Even though the shift shaft seemed to have excessive resistance, it feels fine with it all hooked back up. and ran it on the ear muff and it pumps water!

After reading about proper shifting technique on another thread on here, it made me think maybe something is amiss with my shifting adjustments. I mean, the dog clutch seems to fully engaged, weather in forward or reverse gear.

But when it shifts to the forward gear, I get the “thud” mentioned by others, but then the control handle moves about 2 inches before the RPMs start to come up. But when it shifts into reverse, as the dog clutch engages the, The RPMs jump up instantly ! How do I adjust it so that some of that free play of the lever in forward can be moved over to the lever as it goes into reverse? Is there any adjustment in the control lever box that would remedy this issue?
 
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jerryjerry05

Supreme Mariner
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May 7, 2008
Messages
17,923
Top 3 posts have some great info.
One contains a post by FrankA, called a linc and sinc.
This should help.

You can also try to unhook the end of the shift cable.
Shift into N
Then make sure the drive is in N moving the shifter.
Then adjust the linkage so they match and rehook the connector.

BUT!!! if you have the dreaded thump?? then the dog might be past adjustment
and need a new dog or machine the edges of the old.
 
Joined
Aug 1, 2017
Messages
16
Hey guys, I am about to replace the water pump housing, gasket and impeller on my 70hp (no clue what year it is, early 80s I'd say) It's the first time I do that on a Chrysler (had Yamahas and Mercurys before) but Chryslers have no telltale... Where does the water squirt from? Is it under the gearbox?
I did the following test just to understand where the water outlet is - I removed the lower leg (and checked my water pump. Hhousing is all ruined even though the impeller seems pretty new. Previous owner must have the impeller replaced but not the housing :( so took the gearbox off, put the hose running a bit of water on directly on the intake pipe and the water seems to return from some place right under the block (like a parallel whole with the intake pipe), I also removed the plug on top of the top cylinder and the water flows fine from there (makes me think if I could install a T connector there and send one side to a telltale and the other install my temperature sender for my gauge). But... Is this the normal place where the water comes out? from under the block through to the gearbox? I'm confused. Not having a telltale seems confusing ahahhaah Thanks in advance.
 

jerryjerry05

Supreme Mariner
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May 7, 2008
Messages
17,923
You should start your own thread.

The 70 Chrysler, probably a 79/80

The exhaust/water comes out 2 places.
The snout under the cavitation plate and the hole in the back of the mid section.

The idea about the T is what a lot of people do.
But hooking both to the same spot won't work.
The sending unit for a gauge won't work in flowing water.




The impeller/pump housing is made with pot metal and even in bad shape should work.
It gets holes but seems to still work.
 
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