'94 Mariner 25HP water pump replacement

[fish56]

Yeah, I know, buy a manual, but your help would be greatly appreciated! Bought a used boat, trailor, motor this past fall. Didn't use it yet, just winterized it but found when I did run it to get some stabil in the gas and fog it, that the water pump barely dribbled.
So now before running it, I want to install a new waterpump kit and I need to know, how do you disconnect the shift rod? And when I do, should it be in forward, neutral, or reverse? Otherwise, I suppose all there is to it, is drop the lower end by removing the four bolts just above the anti-cavitation plate.
Thanks in advance!

 

[Laddies]

Re: '94 Mariner 25HP water pump replacement

Look underneath the carb from the port side and you will see the connector remove the bolt or pin which ever your motor has. The gear don't matter on a 25

 

[fish56]

Re: '94 Mariner 25HP water pump replacement

Thanks Laddies,
I looked in that area earlier today and think I saw what you' re talking about. I thought maybe there was a coupling somewhere below that where I'd only be removing a shorter part of the rod.
I'll give it a shot tomorrow. Thanks again.
Bill

 

[fish56]

Re: '94 Mariner 25HP water pump replacement

Laddies,
I installed the new water pump today. As you said, the shift rod was connected by a pin that was part of a locking plastic clip. Had a hard time getting to it, since my outboard is electric start and the starter and starter solenoid were in the way.
When I removed the pump, I found the impeller was indeed bad. It had partially separated from the metal hub. Then when I went to reassemble everything, I found the kit I bought was missing one of the white plastic washers that protect the impeller from rubbing inside the housing. Had to reuse one old one, in OK shape.
After all this, I started the motor and it still isn't getting flow. Very little dripping out. I removed the rubber telltale line where it exits the cowl and rodded it with a short piece of wire, seemed clear. I blew into the hose and could hear the air coming out inside the lower end housing. When the motor was running and no water was coming out the telltale hose, I did see some exhaust from it.
So what'a'ya think? Maybe the grommet that the water tube goes up into failed? I read some posts about thermostats, but because I could blow air through, it would seem if there is a thermostat, it was open and water should have made it's way through.

Thanks again. I hope I can get this problem solved. I'd like to use the boat in about two weeks.

 

[fish56]

Re: '94 Mariner 25HP water pump replacement

Oh yeah, there were two flat gaskets in the kit, even though the original pump had one. They were almost identical. I just installed the one where it had been, under the flat stainless plate. The housing just had an o-ring sealing it to the flat plate.

 

[Laddies]

Re: '94 Mariner 25HP water pump replacement

Bill, it could be the grommet but I doubt it. Were there pieces gone from the imp? the most common problem is imp parts pluging things up. The next problem is gaskets burned out if the thing got really hot. If I were you I would drop the unit again and hook a hose to the tube and see if you have good flow then don't use a lot of pressure the pump developes 6 to 8# If that gets you a good flow the ck the w/pump work and if not your going to ck the w/system in the engine itself gaskets, grommet, etc

 

[Laddies]

Re: '94 Mariner 25HP water pump replacement

Sorry to have forgotten to tell you to ck the gasket under the w/pump plate if it's the wrong one or not sealing well it will let the w/pump suck exhaust gases and give a problem

 

[fish56]

Re: '94 Mariner 25HP water pump replacement

Laddies,
No, impeller didn't seem to have anything missing, just was disconnected around the hub and had the rubber vanes twisted.
I will try your suggestions. Thanks again for the help.

 

[fish56]

Re: '94 Mariner 25HP water pump replacement

Well, finally got back to working on the Mariner water pump. Dropped the lower end. Connected a hose to the water tube going up inside the the housing. Could tell that the rubber grommet up inside felt decent when inserting the water tube. Seemed like I wasn't getting too much flow back through the telltale, and that the water started to spray pretty good from up inside the housing, like the pressure from the hose wasn't making it up through the tube into the motor and was coming back down, blowing out around the rubber grommet inside the housing.
I tried water going back the other way, hooked up to the telltale hose. It seemed all the water being put in was making it's way through properly.
I did check the waterpump. Seemed good, no restrictions, gaskets not torn or out of place, key in place. Would it be good to use some permatex on the gaskets, too, to help with sealing?
Anyway, what do you think? Maybe a gasket or something that's acting like a one-way check valve, up inside somewhere? Also, can you tell me if this model would have a thermostat? If it does, it must be really small to fit inside the housing where the telltale hose is connected to.
I'll probably take off that small housing and take a look. Maybe something in there that's restricting water flow.
When I had run the motor last time, I was getting a lot of water coming from a small hole at the top of the lower end, right behind the shift rod. I can see inside there are passages that allow some water to flow here, though, but probably not at the rate I was seeing it.

Thanks

 

[fish56]

Re: '94 Mariner 25HP water pump replacement

I got this pm from Laddies, after I posted.
"Bill, I have not run into a 25 thats been plugged up like your seems to be, but if I were in your position I think I would start by removing the powerhead from the torque tube as theres 2 gaskets and a adapter plate that could be plugged or leak, when it's apart you can ck the upper grommet and above it there is a spacer some were made of plastic and the holes could melt shut if over heated. If you don't find a problem in this area then there are 2 gaskets under the exhaust water jacket that could be leaking."

Looks like I'll be taking the powerhead off. I tried again to get water to flow up through to the telltale hose. No luck. I blew air through the telltale hose and felt if the air was coming back through the copper water tube below.....nothing. The air seemed to be coming out the exhaust ports just below the head and elsewhere inside the drive shaft housing.

 

[fish56]

Re: '94 Mariner 25HP water pump replacement

Now, earlier I had said I didn't have a manual/book. I do have one, a Clymers, that covers up to 1989. Now with my motor being a 1994, hopefully I can use the book.
I was looking at the description for removing the powerhead. There are a few steps that seem unnecessary, but please correct me if I'm wrong. the steps I'm talking about say that I need to remove the flywheel, stator/triggers assemblies, switchbox, and coils.
Also to remove the rewind starter assembly. And remove the carburetor.
Is all this necessary? Some of the other things make sense, but I would think these could stay on the powerhead?
Thanks

 

[Don S]

Re: '94 Mariner 25HP water pump replacement

Now, earlier I had said I didn't have a manual/book. I do have one, a Clymers, that covers up to 1989. Now with my motor being a 1994,

Nope, that book isn't like the 94, not only that it's the worst of the worst as far as service manuals go.
The Clymers manuals are easy on the wallet, but short on correct information.(aka missprints, wrong information etc. )
If you want to do your own maintenance, and you can't afford the proper manual and tools to do the job, then you really can't afford a boat.

 

[fish56]

Re: '94 Mariner 25HP water pump replacement

OUCH! :^ Don, that hurts! :%

Now, if you can give me some advice about the powerhead removal..............

..........I'll be able to see what's necessary as I remove the six bolts holding the powerhead to the drive shaft housing, just thought I may avoid some grief by asking first.

 

[fish56]

Re: '94 Mariner 25HP water pump replacement

If you want to do your own maintenance, and you can't afford the proper manual and tools to do the job, then you really can't afford a boat.

Correct me if I'm wrong, but I thought this site was here to help boat owners get some answers to their questions. I wouldn't expect the 90,000 people registered here, to have a factory repair manual, for every outboard they owned. As far as the correct tools, I have a good and varied selection, but of course, wouldn't own a lot of outboard manufacturer special tools. Many times, you can make do without the specialty tools, with a little innovation.
And also, as far as tools, the internet has proven itself to be one the most valuable tools there is. Where else can you go, and talk to so many people, to gain knowledge from their experiences, to avoid the mistakes they've made, and maybe to offer your own experiences and knowledge, to help them. This site proves that.
I've learned a lot on the internet, from how to repair my kitchen's gas range to improving my skills performing autobody work, to now, disassembling and repairing one of my outboards.

My sincere thanks to Laddies. I know he's laid up right now. Hope he's feeling better. I definately owe him a beer.

 

[Don S]

Re: '94 Mariner 25HP water pump replacement

The internet is a tool, not a cure all for everything.
Sorry you got your feelings hurt.
We marine techs use service manuals all the time. It's just something pros do if they want to do the job right the first time, DIYers are usually against the idea. Have no idea why. The manuals saves time and money if used.
The manuals are a tool in your tool box, nothing else.

Trust me, Laddies also recommend you get the real service manual.

 

[fish56]

Re: '94 Mariner 25HP water pump replacement

No problem, Don. But as much as the real shop manuals help, you can usually find what you need on the net, nowadays. After I posted, I did another search, and found a site that had the exploded views of my specific motor. Very helpful. Still trying to troubleshoot the problem, getting closer.