Mariner 4 service manual or service info needed

[ProDave]

I have a Mariner 4 2 stroke outboard motor, a fairly recent one.

Last year I downloaded what I thought was the correct service manual, but apparently not.

The two things I want to check out are the sheer pin, and water impeller. Mainly so I know where they are for when I need to change them (which might be at sea)

Firstly the sheer pin. My manual shows this as being the "drive element" between the shaft and the propeller. So I remove my propeller only to find the prop fits onto a splined shaft on my motor.

So does my motor not have a sheer pin, or if it does, where is it?

And that all important impeller. Not mentioned at all in the manual I have. So where is it?

Ideally I need a more up to date, or more correct manual for the motor I have.

 

[Steve Clayton]

This any good? It's the 4 stroke model.

http://www.mercurymarine.com/media/mercury/documents/maintenance-4to6FS.pdf

 

[electrosys]

http://www.youtube.com/watch?v=ZB0ztSvLqig

 

[ProDave]

Thanks for those.

Wow, that's a lot more complicated than I expected. Cetainly not something you would do at sea is it?

I was under the impression it was a simple job to change the impeller and people carried spare, but I don't see the point in that as it's a fiddly job to change it.

My impeller is working just fine, and the motor is peeing nicely, so I think I will just leave it alone.

And I take it the later ones didn't have a sheer pin on the drive either. Although mine is a 2003 2 stroke model, the foot assembly does look identical to the one in the 4 stroke manual above.

 

[electrosys]

Thanks for those.

Wow, that's a lot more complicated than I expected. Cetainly not something you would do at sea is it?

Certainly not - it's recommended that the impellor be checked/replaced during an annual service, but DIY-servicing people tend to change 'em far less often.
Unless you've been running the outboard commercially, it's unlikely that you'll need the full impellor repair kit. But having just a spare impellor handy is useful, then, during a routine check if there is even the faintest trace of cracked or otherwise damaged rubber, you can replace that impellor immediately ... as Sod's Law says the suppliers will be out of stock exactly when you need one.

My impeller is working just fine, and the motor is peeing nicely, so I think I will just leave it alone.

When was it last changed ? It's highly desirable to know the engine's service history ... as the impellor will work 'just fine', until one day it falls apart, maybe at a most inconvenient moment.

And I take it the later ones didn't have a sheer pin on the drive either. Although mine is a 2003 2 stroke model, the foot assembly does look identical to the one in the 4 stroke manual above.

There's a shear-pin list at:
http://www.seamarknunn.co.uk/download/shearpins/shearpinlist.pdf

Mine's a 5HP 4-stroke, 1990(ish) - with no shear-pin. Can't say I'm too thrilled abaout that, but what do you do ... ?

 

[ProDave]

Thanks again for the repies.

I had obviously got the wrong end of the stick somewhere. I'm sure I have read threads about impellors, and the need to change them regularly, and had formed the opinion they were a simple 5 minute job to change, and looked a bit like a long thin screw (cartesian screw) type of thing. Obviously that certainly wasn't for this particular motor.

While I still accept the wisdom of checking it, and if there's the slightest doubt replace, it's allas too late as we launch on Wednesday. I'll keep an eye on it, and as long as the motor pees okay, I'll leave alone. If it stops peeing, then I'll have to bring the motor home to fix it, otherwise I'll be better prepared to give it a more thorough overhaul next winter. The motor came with the boat that we only bought last September so service history unknown.

As to the (lack of ) shear pin, well that's only an issue if we hit anything with the prop, which I will try very hard not to.

I started the thread to help me do these simple things! only to find they are not so simple. At least now I know.

 

[VicS]

It is correct that a 2003 4 hp 2 stroke Mariner does not have a shear pin.

The prop has a rubber hub. that will absorb minor shacks but is designed to slip in the event of a major impact event.

Keep bashing it and making it slip and you will find that it will tend to slip every time you pile on the power.

Tell us the model number and it might be possible to locate some diagrams .

Water pump impellers are rubber multi-vane impellers. It is advisable to change them periodically. Some fixed drive models have the pump behind the prop. They are relatively easy to service.

All ( water cooled) outboards with a neutral gear position have the water pump located on top of the gearcase necessitating removal of the gear case to access it

 

[ProDave]

Thanks again.

I can't find a model number. The only plate on the motor confirms it's a 4HP made in 2003 my Marine Power Equipment Inc Verviers and made in Belgium. There's a serial number, but no model number.

 

[VicS]

Thanks again.

I can't find a model number. The only plate on the motor confirms it's a 4HP made in 2003 my Marine Power Equipment Inc Verviers and made in Belgium. There's a serial number, but no model number.

I should have said serial number. Sorry.

A 2003 model should be in the range OP210982 to OP270558 but I dont need to know it after all

All the exploded diagrams and parts lists are HERE

 

[ProDave]

Many thanks, that's now bookmarked, and later I'll print a hard copy of those diagrams.

 

[SAMYL]

PBO did an article about servicing that very engine about a year ago so have a search through their old copies.
The article was about servicing 'your outboard' but didn't mention the Mariner by name but that was the engine they used.
I sent my copy to someone who had posted on here looking for advice, so sorry, it has gone now.