Replacing Mercruiser Water Pick Up Hose

scottyt22

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Mercruiser 1998 V8 5.0 - I want to replace the water pick up hose on my mercruiser - can someone point me to a picture where this is located or tell me? Is this something that is easy to do - eg, I am not a mercruiser mechanic just a regular guy with basic mechanical skills.
 

Don S

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Re: Replacing Mercruiser Water Pick Up Hose

The OEM service manual for your particular drive details how to change it, but I really have to ask WHY you want to change it when you don't even know what it is or where it's located? Also, what kind of outdrive is it?
There are OEM service manuals for download at the link below
http://forums.iboats.com/showthread.php?t=251571
 

scottyt22

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Re: Replacing Mercruiser Water Pick Up Hose

I could not find the manual for the alpha one engine itself 1998, only one for the outdrive/transom. Do you have a specific link to the manual for me?

It was recommended on this forum that to correct a high temp problem at slow trolling speeds to replace the water pick up hose which tends to kink over time, and to replace the elbows/risers. Already replaced the impellor.
 

Don S

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Re: Replacing Mercruiser Water Pick Up Hose

It was recommended on this forum that to correct a high temp problem at slow trolling speeds to replace the water pick up hose which tends to kink over time, and to replace the elbows/risers. Already replaced the impellor.

You don't seem to quite understand the concept. This forum makes all kinds of suggestions, some are right some are wrong. What you have to do is find out exactly what is wrong with your engine and drive and not fix what is wrong with others. All that does is costs you a lot of money for replacing parts that aren't the problem.

As far as engine manual, well, that depends on what engine you have.
You might want to read this thread before you go any further.
http://forums.iboats.com/showthread.php?t=220416
 

ken_23434

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Re: Replacing Mercruiser Water Pick Up Hose

I could not find the manual for the alpha one engine itself 1998, only one for the outdrive/transom. Do you have a specific link to the manual for me?

Alpha-1 is the outdrive (part hanging off back of the boat)

You engine (part inside boat) can be various different models. 3.0 liter inline 4, 4.3 liter V-6, 5.0 or 5.7 liter V-8's.

There is a water hose in the transom assembly for the Apha-1 Outdrive. You will also have water hoses inside the boat, the locations and function depends on the engine you have and if it is freshwater cooled or raw water cooled.
 

scottyt22

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Re: Replacing Mercruiser Water Pick Up Hose

My engine is a 5.0. I called Mercruiser and here is the water pick up hose part number: 32-96246A4. Now friends, back to my question, does anyone have a picture of where this hose is located? It supposadly connects from the main engine to the transome.
 

bomar76

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Re: Replacing Mercruiser Water Pick Up Hose

Since you just want to throw parts at it instead of diagnosing, my suggestion would be to go out to the boat and look in the transom assebly.
 

NHGuy

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Re: Replacing Mercruiser Water Pick Up Hose

It is pictured in the alpha 1 documentation. It goes from the forward facing inside of the drive to a barbed fitting on the transom assembly. It is a huge pain in the derriere to do the 1st time. I know... I changed the one on my 89 last year due to cracks and kinks. I wrestled with that thing for a while. It might have been harder for me though because I have oversized hands. The hose length is very important to keep it the correct shape.
But even more important is the advice you already received.
If you go through the diagnostic process you may be able to save hours of time.
The hose is nothing more than good quality automotive heater hose, it is no high tech stuff. It's just a tough piece to install.

Your smart move is to go the the adults only section in "Mercruiser & other I/O engines and drives" where you can get a link to a free download of the alpha 1 manual from Mercruiser. It goes into every possible detail. Including a process you can follow pretty easily to confirm water flow using a clear hose.
 

dingdongs

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Re: Replacing Mercruiser Water Pick Up Hose

have a good look on you ;www.youtube.com ,mercruiser and most engines are shown in picture form and general maintenance procedures with video capture.will be helpful for most basic maintenance.
if your having trouble cooling engine unless your pipe has a gaping hole in it, the trouble probably lies at the impellor in lower leg hanging out the back of your boat. find your problem first then ask for further help.
 

scottyt22

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Re: Replacing Mercruiser Water Pick Up Hose

Well I just bought the various parts and here is what I'm going to do - I'll let everyone know how it turns out. I will replace all the water hoses because I don't think they have every been replaced since 1994. Going to replace the thermostadt. Going to replace the Riser gaskets.
 

betayv

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Re: Replacing Mercruiser Water Pick Up Hose

how was the impeller when you replaced it, was missing any parts, what about the thermostat housing and the termostat, like they say just dont trow parts, you probably will keep having the same problem...
 

jtmarten

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Re: Replacing Mercruiser Water Pick Up Hose

What issue are you having that points you to the pickup hose? Is it visually leaking/pouring water from it while running on the muffs? On an Alpha 1 Gen1 it runs around the left side of the gimbal ring, tight against the transom housing.
 

scottyt22

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Re: Replacing Mercruiser Water Pick Up Hose

Here are the results - I replaced the old thermostadt and all the water hoses. The risers and gaskets seemed fine - no leakage and no dirty discharge when the hoses were removed - so left them alone. Put the old thermostadt in hot water and it never opened up.

Anyway, took the boat out and at very slow trolling speeds it stayed cool most of the time. It did still heat up to 200 degrees every once in a while, but cooled down quicker and stayed cool longer, when I reved the engine up in neutral or went faster. So still not perfect.

So you can see that the engine still seems to be heating up more than it should. Someone mentioned that the radiator hot water sensor may be bad, so I'm going to replace that next and see what happens.
 

Bondo

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Re: Replacing Mercruiser Water Pick Up Hose

The risers and gaskets seemed fine - no leakage and no dirty discharge when the hoses were removed - so left them alone.

Ayuh,... If you don't pull the Risers, you can't see how Plugged up they are....
 

scottyt22

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Re: Replacing Mercruiser Water Pick Up Hose

I did pull one of the Risers, clean as a whistle.
 

jtmarten

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Re: Replacing Mercruiser Water Pick Up Hose

Was the old impeller shredded? Did you check the PS cooler to make sure it isn't clogged with old impeller pieces?
 

fyrfightr

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Re: Replacing Mercruiser Water Pick Up Hose

Was the old impeller shredded? Did you check the PS cooler to make sure it isn't clogged with old impeller pieces?

I don't see where he replaced the impeller?? Sounds like a good step to take. But it doesn't sound like he followed Don's advise either.
 

scottyt22

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Re: Replacing Mercruiser Water Pick Up Hose

The impeller was replaced by a mercruiser mechanic, the old impeller was not shredded and came out clean. I can only assume the marine yard mechanic did his job properly.

So we have an engine that still heats up when trolling on the slowest in gear speed for long periods of time. It cools down quickly when I rev it up or speed up. With the radiator replaced it seems to stay cooler longer and cools down quicker.

What's been done so far?

- Impeller replaced
- All water hoses replaced
- Radiator replaced (Note, the old radiator did not open at all in hot water)
- Pulled one of the Risers, all clean, replaced gasket and re-installed

Next I'm going to replace the Water Temp Sender and check the wire for corrosion.

Any other suggestions are appreciated!
 

scottyt22

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Re: Replacing Mercruiser Water Pick Up Hose

Sorry, yes correct, I replaced the Thermostate. That was a fun project, the toughest part was getting the old gasket off.
 
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