8.1 Horizons Replacing Water Pumps and Manifolds

Nice Work!
How did you start? did you remove the exhausthoses first then the risers and the manifolds?

/ Kim
 
M Prod said:
Great advice will do! That looks familiar. :) I'm still dreading the day when I need to replace shaft seals. Not sure how I'm going to get down between those engines and still be able to move.
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Just replaced shaft seals on my 2002 a real pain. The Tides (blue bellow hose) is a real bad design metal on metal. Wore the shaft a bit. Went with the PSS carbon seals and was able to get by the grove in the shaft. Pretty tough job, consider taking the engines out if the old seals show any drips...
 
tides SS.JPG
 
Did you have any problems with bolts breaking on the manifolds? Did u use the pb blaster before trying to remove?
 
liv2ryde100 said:
Did you have any problems with bolts breaking on the manifolds? Did u use the pb blaster before trying to remove?
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I didn’t have any issues with them breaking, but did have issues with them getting stripped (why I had to get new ones) as I unscrewed the bolts. Might have not happened had I lubed, but oh well. I think the manifolds had been replaced within the last 5 years or so, so the bolts likely weren’t that old.

Kimpa said:
Nice Work!
How did you start? did you remove the exhausthoses first then the risers and the manifolds?

/ Kim
Click to expand...

Yes, removing exhaust tubing and then mufflers was the first step as we tackled water pumps first. No way to get at water pumps without removing mufflers.
 
Ok thanks, I’m trying to decide if this job is for me or I should have mechanic do it
 
liv2ryde100 said:
Ok thanks, I’m trying to decide if this job is for me or I should have mechanic do it
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It’s a really difficult job ...much moreso than it looks on paper. What I planned as a one day job became 3 days. If you haven’t done something like this before and don’t have a very handy ‘mechanic’ friend you can call on if needed (which I did), then I don’t recommend tackling this alone.
 
Well i started last weekend with my boat, first manifold 3 bolts snapped... other side 3 bolt heads where stripped after that i went home to calm down :) one beer later and in now looking forward to next weekend challanges.
Im now equipped with torches, dremel tools, ect to fight back
 
Kinda late now but in the future or for others. Squirt penetrating oil on the bolts and let sit for 24 hours. Helps not to break or strip the bolts.

What you'l need now is a reverse drill bit that bites the head of the broken bolt and extracts it out. Go slow! But squirt some penetrating oil in there first and let it soak.

You may need to retap the bolt hole. No big deal just move up one size.
 
Going back to the water pump situation I did mine this weekend. I spent more time trying to figure out how to remove the pump without pulling the exhaust hose. In the end, I pulled the hose (port side exhaust off riser) and set it aside. I had to remove the fuel/water separators - I have the spin on kind. That gave me some access to the clamps. From there I just pulled the pump after removing all the other stuff (belts, idler pulleys, etc etc). I did the same thing for both motors. Stbd side was a little easier just because you didn't have to hang upside down to get to the clamps for the hoses.
 
DaleM said:
Going back to the water pump situation I did mine this weekend. I spent more time trying to figure out how to remove the pump without pulling the exhaust hose. In the end, I pulled the hose (port side exhaust off riser) and set it aside. I had to remove the fuel/water separators - I have the spin on kind. That gave me some access to the clamps. From there I just pulled the pump after removing all the other stuff (belts, idler pulleys, etc etc). I did the same thing for both motors. Stbd side was a little easier just because you didn't have to hang upside down to get to the clamps for the hoses.
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Yeah no real way to get at them unless you remove exhaust hoses/mufflers ...especially on port side. Those water pumps are major pains.
 
Well now i did my second day and all the manifolds are finally off..

The key for success was not force, to bad I learned that after one engine :) as LG111 sad, a lot of oil and pressure on the bolt, oil and pressure then the will come out.

Now to the snapped bolts. I had 15mm of the bolt sticking out from the block, oil and bang with the hammer and wait one hour oil some Moore and when the oil penetrated the rust they almost came loose by hand.

The stripped bolts i used the dremel tool and cut the heads off the bolts and then the same procedure as above.

With a total of 32 bolts one snapped second time close to the block after i tryed the torch.. and thats the last one i have left!

I am also thinking of changing the waterpumps but from the back they look brand new, no rust at the screws what so ever, so maybe the back and the impeller was changed before...


image_1.jpeg
 
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LG111 said:
Kinda late now but in the future or for others. Squirt penetrating oil on the bolts and let sit for 24 hours. Helps not to break or strip the bolts.

What you'l need now is a reverse drill bit that bites the head of the broken bolt and extracts it out. Go slow! But squirt some penetrating oil in there first and let it soak.

You may need to retap the bolt hole. No big deal just move up one size.
Click to expand...

I totaly agree, second engine worked out fine. Yeah i bought a PRO set i got tipped from a mecanic there you start with drillning a deep center hole into the bolt and then you hammer in a pin with long threads in the hole and on the pin you add a nut that you grab on to unscrew the bolt. They say that this way will not expand the threads..

I hope this is going to work.

IMG_5448.jpg
 
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P B Blaster is a good product to spray onto bolts, I think its a lot better than penetrating oil seems to soak in better and work faster.
 
Wow. Feel bad for you. Mine were in service 10 years - 5 in salty LI sound, 5 in brackish river water here in NJ. All 32 came out with a good old socket.

But I know your pain...broke off 6 of 32 bolts on my previous boat ('89 with 7.4s). Had the marina get a few of them off with a torch, the others required removing the head and taking it to a machine shop to pop out the super corroded ones.

Merc used stainless fasteners on the 8.1s so the seizure isn't as severe. 7.4s don't.
 
What is that method for drilling into the bolt head and putting a pin in there with a nut? I’m lost on that part. I’m going to try the Kroil penetrating oil, supposed to be a good product. And I guess I should invest in an extractor set before I go down there just in case
 
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