SteveIOW
Member
Can anyone please advise me on the torque for the four cylinder head bolts on a Yamaha 2B outboard.
Yamaha 2B Outboard
- Thread starter SteveIOW
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Poignard
Well-known member
SteveIOW
Member
Thank you Poignard.
Have just noticed that the torque and tightening sequence is embossed on the cylinder head casting!
Have just noticed that the torque and tightening sequence is embossed on the cylinder head casting!
Poignard
Well-known member
If you want it, I have a PDF of the workshop manual. If you want it I could send you a copy.
SteveIOW
Member
Thank you Poignard. Sorry for a very slow response to your kind offer but a workshop manual for the Yamaha 2B would be most useful. My email address is SteveCurtisIOW@hotmail.co.uk
Mark-1
Well-known member
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SteveIOW
Member
Having cleared all waterways at the power head end and checked that the pipe from the pump to the block is clear have found that cooling water still not circulating.
Have now removed gearbox section below leg to gain access to water pump. As you see drive shaft and tube came away with it.
My question is, do I have to remove the prop shaft cover and “circlip?”on the drive shaft in order to remove water pump and replace impeller? Any advice welcome.
Have now removed gearbox section below leg to gain access to water pump. As you see drive shaft and tube came away with it.
My question is, do I have to remove the prop shaft cover and “circlip?”on the drive shaft in order to remove water pump and replace impeller? Any advice welcome.
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Mark-1
Well-known member
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Steve65
Active member
Yes you do...
Are you sure the issue is the impeller?
A 3/8 hex drive fits the driveshaft...put a drill on the hex drive and a piece of pipe into the pump housing where the water pipe usually located, remove the prop, put the gearbox in a bucket and spin the driveshaft with a drill. If it's pumping water well you either still have a blockage or a water seal gone.
If it's not pumping you need an impeller
SteveIOW
Member
Thank you Steve65 for suggesting use of electric drill, bucket of water and pipe at pump discharge to check impeller. That is exactly what I had already done (great minds think……) Unfortunately no water came out of the pipe.
When I first ran the outboard in a bucket of water before taking it to pieces I did notice water coming out of a hole on the forward side of the bottom the leg just above the anti cavitation plate. Just above arrow on photo. Had never noticed this before. Any suggestions why this happened? Could seal on pump body have failed?
Have ordered pump repair kit and started dismantling ready for reassembly. Any suggestions please on how to remove stainless “cup” in which the impeller fits. There’s nothing to get hold of to pull it out of the casting. See photo 2.
Help required please.
When I first ran the outboard in a bucket of water before taking it to pieces I did notice water coming out of a hole on the forward side of the bottom the leg just above the anti cavitation plate. Just above arrow on photo. Had never noticed this before. Any suggestions why this happened? Could seal on pump body have failed?
Have ordered pump repair kit and started dismantling ready for reassembly. Any suggestions please on how to remove stainless “cup” in which the impeller fits. There’s nothing to get hold of to pull it out of the casting. See photo 2.
Help required please.
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alahol2
Well-known member
If I remember correctly it was a case of having to more or less destroy the inner, stainless, cup to remove it. Tap the edges of the cup away from the aluminium seating using a small screwdriver and a hammer
I think the small hole you mention is the drain hole for the leg when the engine is tilted after use.
I think the small hole you mention is the drain hole for the leg when the engine is tilted after use.
SteveIOW
Member
1.Think you are right about hole being a drain when outboard is tilted but can’t understand how or why water is being piped out of there when engine is running.
2.Have tried to free stainless steel “cup” by punching it inwards as suggested above but it still doesn’t want to come out. Currently have recesses created soaking in WD40. Surprised it’s so tight as cup sits in nylon liner just visible in photo.
Any suggestions welcome for both paras 1 and 2.
2.Have tried to free stainless steel “cup” by punching it inwards as suggested above but it still doesn’t want to come out. Currently have recesses created soaking in WD40. Surprised it’s so tight as cup sits in nylon liner just visible in photo.
Any suggestions welcome for both paras 1 and 2.
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VicS
Well-known member
The cooling water is discharged from the power head into the exhaust housing, as are the exhaust gases, most will leave via the exhaust outlet but some will exit via any other openings such as this drain.
You are only able to see this because you have not submerged the lower unit deeply enough. Find a deeper container for the water.
SteveIOW
Member
I not sure any water was getting to head. The exhaust noise was different than normal and not a drip of water was coming out of the tell tale holes half way up the leg (the holes covered by the black plastic cowling which diverts the discharge downwards.)
alahol2
Well-known member
You will only get spits of water from the tell-tale holes if there is pressure in the leg of the engine. If the leg of the engine is not deep enough in the water there will be no pressure. You will also get the 'hollow' exhaust sound.
As Vic said submerge the lower unit more deeply.
SteveIOW
Member
You were right about having to destroy the stainless cup to remove it. Having hammered inwards to form the star shape in photo above and having soaked the recesses created in WD40 I still had to cut slits in the cup with Dremmel type tool and apply heat before it wood come out. The heat didn’t do the water seal under the cup any good but think there is new one in repair kit. My question is: Is there a drive shaft oil seal directly below the water seal and can it be replaced from above. Or, if there is an oil seal there is it necessary to remove the vertical shaft bearing tube?(I hope not)
I presume this tube is in two parts as it looks to be too long to come out of the gearbox housing in one piece. How would one remove and replace this tube if it had to be disturbed?
An exploded view with part numbers of the lower part of this outboard (Yamaha 2B) would be a great help.
I presume this tube is in two parts as it looks to be too long to come out of the gearbox housing in one piece. How would one remove and replace this tube if it had to be disturbed?
An exploded view with part numbers of the lower part of this outboard (Yamaha 2B) would be a great help.
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alahol2
Well-known member
I haven't got part numbers but I have got a diagram...
VicS
Well-known member
The part numbers can be found here:- https://www.boats.net/catalog/yamaha/outboard
The year of the outboard in question has not been stated so select the year and then navigate to 2 hp and to the relevant parts list. There are some small changes over time.
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SteveIOW
Member
Thank you for info. Outboard serial number is 6A1 050363 but don’t how that ties down the year of manufacture.
