Mariner/Yamaha 2hp (1984) Informatiopn?

[Larsen B]

Hi


I have just acquired an old Mariner (yamaha built) outboard. It is one of the small 2hp versions. Considering its age it runs really well and is a fiesty little motor at only 10kg.

The model number is Mariner 2M 6A1 and the serial is 076465. I think this makes it about 1984. I managed to get a service manual for Yamaha 2B/2C/2U models and my motor looks almost identical. Mine appears to be a slightly older version and looking at it I assume it has points rather than CDI ignition.

Is anyone able to offer any advice on this version. I am not too sure what the ideal spark plug is or the plug gap. I havent had a look at the points yet, but any advice on setting them also if I need to would be great. I am assuming it i8s best to run this on 50:1?



Here is a photo of it minus the cowl and the tank.



Thanks

 

[sailorman]

Hi


I have just acquired an old Mariner (yamaha built) outboard. It is one of the small 2hp versions. Considering its age it runs really well and is a fiesty little motor at only 10kg.

The model number is Mariner 2M 6A1 and the serial is 076465. I think this makes it about 1984. I managed to get a service manual for Yamaha 2B/2C/2U models and my motor looks almost identical. Mine appears to be a slightly older version and looking at it I assume it has points rather than CDI ignition.

Is anyone able to offer any advice on this version. I am not too sure what the ideal spark plug is or the plug gap. I havent had a look at the points yet, but any advice on setting them also if I need to would be great. I am assuming it i8s best to run this on 50:1?

View attachment 29985

Here is a photo of it minus the cowl and the tank.

View attachment 29984

Thanks

Hi a superb o/b, i would run on 50>1 ( Tohatsu built they made Yams as well).
it might be worth checking the impeller but i have an older one with original one

 

[VicS]

Yes nice little motors ... the person I sailed with for many years had the Yamaha one.

Yes the serial number makes it a 1984 model

I agree 50:1 for the fuel ... thats what Mariner say anyway !

I agree also to change the pump impeller if you dont know when it was last done. You dont want to run it until it does not pump and overheats. BUT be very careful with bolts that have not been undone for years

You can down load the Mariner owners manual from http://download.brunswick-marine.com/download/preparesearch?mod=4&lang=EN but dont specify the year etc .. pick it from the whole list of outboard manuals

Listed under Mariner 2-4-5


Parts lists and diagrams http://www.boats.net/parts/search/Merc2/Mariner/2B/6A1-000101 AND UP/parts.html

 

[awol]

If it runs well and there is a tell-tale of water leave it alone 'cos it ain't broke. Mine has a label saying 100:1 but I usually add more.

 

[Larsen B]

Thanks for the replies! Thanks for the links too, very useful. Even though it is almost 30 years old I think it might have had a relatively easy life. The paintwork and cowl cover are tatty, but underneath it is nice and corrosion free. So far I have just been tidying it up. Cleaned the fuel tank and pipes, but not tackled the carb (they look a lot more fiddly than my old seagull carb!).

It was pumping some water when I ran it is a test tank, especially with a few revs, but hardly any when I dropped the revs to near tick over. I dont know if this is normal. There are one or two videos of these running on youtube and some seemed to be chucking out more water than mine. I also dropped the leg to check the impellor, fortunately no bolts seized and it came off quite easily. The impellor look in good condition to me, but not being familiar I wouldn't really know, here it is:


Not sure if I should be adding some instant gasket to that seal or not when I re-assemble it? I also squirted some limescale cleaner through the head while I had it in bits and it seemed to flow through quite well afterwards with a few bits of gunk coming out in the water. Hopefully this will help.

Any ideas on spark plugs and plug gaps for this points version?

I have decided to paint the thing to smarten it up a bit, so am in the process. It is getting ford metallic sea grey paint, and some clear lacquer(because thats what colour my car is and I had some paint handy) you can see the colour in the photo. It isn't a pro job but it is looking a lot more presentable !

 

[VicS]

Thanks for the replies! Thanks for the links too, very useful. Even though it is almost 30 years old I think it might have had a relatively easy life. The paintwork and cowl cover are tatty, but underneath it is nice and corrosion free. So far I have just been tidying it up. Cleaned the fuel tank and pipes, but not tackled the carb (they look a lot more fiddly than my old seagull carb!).

It was pumping some water when I ran it is a test tank, especially with a few revs, but hardly any when I dropped the revs to near tick over. I dont know if this is normal. There are one or two videos of these running on youtube and some seemed to be chucking out more water than mine. I also dropped the leg to check the impellor, fortunately no bolts seized and it came off quite easily. The impellor look in good condition to me, but not being familiar I wouldn't really know, here it is:


Not sure if I should be adding some instant gasket to that seal or not when I re-assemble it? I also squirted some limescale cleaner through the head while I had it in bits and it seemed to flow through quite well afterwards with a few bits of gunk coming out in the water. Hopefully this will help.

Any ideas on spark plugs and plug gaps for this points version?

I have decided to paint the thing to smarten it up a bit, so am in the process. It is getting ford metallic sea grey paint, and some clear lacquer(because thats what colour my car is and I had some paint handy) you can see the colour in the photo. It isn't a pro job but it is looking a lot more presentable !

Cannot tell much about the impeller without taking it out. If old you'll find the vanes permanently bent over with no springiness. May also be cracked at the roots.
Having opened it it change it. Not worth putting an old one back.

There are no gaskets in the water pump. Dont get liquid gasket in it!. There are seals above and below and an O ring. Parts diagram shows which way up the seals go

While you are fettling it up change the gear case oil. Hopefully old oil will be water free and "clear and bright" other wise you may have to renew seals. Only a single seal on the prop shaft I notice so a little water ingress may be inevitable.... good reason to change the oil regularly

Plug listed in the manual is NGK B5HS gapped at 0.55mm ( 0.021")

 

[longjohnsilver]

I have one and the Yamaha manual states 100:1 although I'd probably run it a little richer than that. There seems to be a wide choice of spark plugs NGK B4H,B5HS B6HS B7HS B8HS10 B9HS. Going down in scale from hot to cold. However I've never had cause to change the plug in any of the engines I've owned.

Great little engines, have had a few of them. Last one I kept in a locker for a few years, still started second pull. Treasure it, there's nothing modern to touch it.

Have just pulled out an earlier owners manual from 1978 for a Yam 2 and the plug recommended is an NGK B-6HS with a gap of 0.020 - 0.025"

 

[VicS]

I have one and the Yamaha manual states 100:1 although I'd probably run it a little richer than that. There seems to be a wide choice of spark plugs NGK B4H,B5HS B6HS B7HS B8HS10 B9HS. Going down in scale from hot to cold. However I've never had cause to change the plug in any of the engines I've owned.

Great little engines, have had a few of them. Last one I kept in a locker for a few years, still started second pull. Treasure it, there's nothing modern to touch it.

Mariner manual states 50:1 fuel mix. Also gives B5HS as the plug type

 

[alahol2]

It was pumping some water when I ran it is a test tank, especially with a few revs, but hardly any when I dropped the revs to near tick over. I dont know if this is normal. There are one or two videos of these running on youtube and some seemed to be chucking out more water than mine. I also dropped the leg to check the impellor, fortunately no bolts seized and it came off quite easily. The impellor look in good condition to me, but not being familiar I wouldn't really know, here it is:

That looks almost unused, lucky you. The impeller on mine is, so far as I know, original and still working fine. No point in replacing it. The water flow out of the tell-tale on the leg is only a mist that gets blown through by the exhaust gasses so you don't get a constant flow, especially at tickover.
My plug is a B5HS and I run it at 50:1.

 

[Larsen B]

Thanks, great advice as usual.

The motor came with a B9HS plug and it ran fine in the tank. I have a new B5HS as a spare so when I get it out on the water I can try both. So the B9 is the colder plug, what difference should I expect when running each type?

Does anybody know the procedure for actually removing the impellor from this model. As you can see in the photo in my earlier post I have removed the leg and undone the water housing, so I can see the impellor, but I can only slide the housing up an inch or two as shown. The tubing over the drive shaft wont move up any further than this, is it supposed to, or do I have to release the drive shaft by dismantling the gear box first? Once I figure how to change it I will have a look at the old one and if its ok carry a new one as a spare.

I changed the gear oil for some new EP90, the old stuff was not exactly totally clear, but not milky either, just a bit dull and slightly dirty looking.

Thanks

 

[VicS]

Thanks, great advice as usual.

The motor came with a B9HS plug and it ran fine in the tank. I have a new B5HS as a spare so when I get it out on the water I can try both. So the B9 is the colder plug, what difference should I expect when running each type?

Does anybody know the procedure for actually removing the impellor from this model. As you can see in the photo in my earlier post I have removed the leg and undone the water housing, so I can see the impellor, but I can only slide the housing up an inch or two as shown. The tubing over the drive shaft wont move up any further than this, is it supposed to, or do I have to release the drive shaft by dismantling the gear box first? Once I figure how to change it I will have a look at the old one and if its ok carry a new one as a spare.

I changed the gear oil for some new EP90, the old stuff was not exactly totally clear, but not milky either, just a bit dull and slightly dirty looking.

Thanks

The B9 plug might foul .

Looking at the parts diagram in my earlier link, I think you have to release the vertical drive shaft by removing the snap ring from the bottom and pulling it from the gearcase.

More usually the shaft pulls from the crank shaft and the water pump components slide up the shaft but in this one the shaft appears to be larger in diameter above the pump!

Bit of a pain if you have already changed the oil ... but I guess its not many gallons to waste!


Maybe a manual that covers it at http://boatinfo.no/lib/library.html

 

[alahol2]

VicS is right, you have to open the gearbox and remove the snap ring from the end of the drive shaft (watch it doesn't spring into oblivion). The drive shaft will detach at the engine end as will the stainless drive shaft cover. The cooling water pipe will pull out from the pump. I tried to remove the drive shaft cover from the pump and now have mole grip shaped dents and scores all round it, don't bother trying.
Here's my take on the process... http://www.troppo.co.uk/odds/Mariner%202M%20Impeller%20replacement.pdf

 

[SteveIOW]

I too have acquired one of these recently. It's a Yamaha (not Mariner) 2B. In good condition and runs very well. Would like to know how old it is. The Serial Number is 6A1 162904. Can anyone out there match the year to the serial number please?

The 2B is basic compared with what I had before with no neutral gear, twist grip throttle, shallow drive...but the big plus is its light weight. My old outboard was air cooled - noisey but no water pump to worry about. I've been bringing the 2B home to flush through with fresh water after each use on the dinghy. A lot of owners leave similar water cooled outboards permanent locked to their dinghies afloat at pontoons. How do the get away with never flushing?

 

[VicS]

I too have acquired one of these recently. It's a Yamaha (not Mariner) 2B. In good condition and runs very well. Would like to know how old it is. The Serial Number is 6A1 162904. Can anyone out there match the year to the serial number please?

The 2B is basic compared with what I had before with no neutral gear, twist grip throttle, shallow drive...but the big plus is its light weight. My old outboard was air cooled - noisey but no water pump to worry about. I've been bringing the 2B home to flush through with fresh water after each use on the dinghy. A lot of owners leave similar water cooled outboards permanent locked to their dinghies afloat at pontoons. How do the get away with never flushing?

That serial number corresponds to a 1990 Mariner ! Yamahas have a "year letter" in one of the bottom corners of the ID plate

http://www.storesonline.com/site/573683/page/599222 .


.

 

[VicMallows]

VicS is right, you have to open the gearbox and remove the snap ring from the end of the drive shaft.

Here's my take on the process... http://www.troppo.co.uk/odds/Mariner%202M%20Impeller%20replacement.pdf

Superb pics. Just wish I'd had them 10 years ago instead of having to work it out the hard way!. (and take care of that circlip or it will cost you a fortune!).

It's usual when replacing the impeller to also replace the housing, which will probably be nicely corroded into the ally casting and messy to remove.

 

[Larsen B]

Excellent. those photos were just what I need, now saved in my folder of pdf files on Mariner / Yamaha. Getting the front cap off the gear box took a bit more effort than I expected and that e-clip holding the pinion gear was a bit tricky! The impeller wasnt too bad, one of the fins was starting to split very slightly and it had lost a little bit of "spring" I have ordered a new one anyway.

Everything else looks in good condition down there, the gears look like new. I did find a damaged oil seal though, the one which sits in the top of the water housing and butts up against the stainless tube surrounding the drive shaft. I managed to get it out and the rubber is split and one of the garter springs damaged. Looking around there are a few companies that do oil seals off the shelf.

http://simplybearings.co.uk/shop/index.php?cPath=19_4463

Would one of these suit for that seal? Measuring mine I make it a 10mm bore, 20mm outside diameter and 8mm thick. Or can anyone give me a specification for a replacement seal?

Thanks again for all the help.

 

[VicS]

I did find a damaged oil seal though, the one which sits in the top of the water housing and butts up against the stainless tube surrounding the drive shaft. I managed to get it out and the rubber is split and one of the garter springs damaged. Looking around there are a few companies that do oil seals off the shelf.

http://simplybearings.co.uk/shop/index.php?cPath=19_4463

Would one of these suit for that seal? Measuring mine I make it a 10mm bore, 20mm outside diameter and 8mm thick. Or can anyone give me a specification for a replacement seal?

Thanks again for all the help.

Where they will come into contact with salt water the springs must be stainless steel or they will rust!

 

[Larsen B]

Ok thanks Vic. I looked again at the spec for one which should fit (its a 20mmx10mmx 7mm thick) and it does say suitable for marine use? I have noticed though that they only have one garter spring whereas the original had two?

 

[VicS]

Ok thanks Vic. I looked again at the spec for one which should fit (its a 20mmx10mmx 7mm thick) and it does say suitable for marine use? I have noticed though that they only have one garter spring whereas the original had two?

The one at the top of the pump maybe not so critical as the one at the bottom. I think it only seals the top of the pump wheres the one underneath is the seal between the pump and the gearcase, a place where larger engines would most likely have two seals back to back

I dont know where you are going for spares but i believe Oakley Marine, aka Outboards-direct, in Brighton are Mariner agents. A good reputation I believe and I've had good service from them for an Evinrude part I wanted.

 

[Gnjoutside]

Evening All,

After rescuing exactly this engine from a loft I've just stripped and serviced it - fortunately following VicMallows route - by luck rather than judgement!

Tried to run it up yesterday - outside in this weather and for the first time this century - no firing...

Is that inevitable at the temperatures we have had? Or could there be something more fundamentally wrong? I am simply getting no spark at all despite clean and well made connections, the original (cleaned) plug and good fuel flow with the correct mix.

New to mechanics I'm afraid - any thoughts welcome.

Larsen B - apologies for the slight hijack!