Mariner 2HP

[Johnjo]

Impellor is knackered, so undone the bolts above the gearbox and removed the bottom of the leg complete with the drive shaft, then undid the bolts on the impellor housing and separated the cover from the housing.
Now for the problem, the cover complete with the drive shaft will only separate about a inch, can see the impellor or whats left of it, but cannot get to it !...
Bit early days to take a hammer to it, so what am i missing ?

regards mike

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[jerryat]

Hi Mike,

You have done most of the work you'll be delighted to know! Here I will have to assume things. The drive shaft passes through the impeller, and turns it via a tiny s/s pin that passes through the drive shaft and locates in the impeller slots. You'll see what I mean later. In order to remove the drive shaft, you need to remove the propeller, then remove the two bolts exposed and remove the plate (there is an 'o' ring here that it is worth replacing on reassembling) AFTER having drained the gearbox oil!

Remove the prop drive shaft and the two gear wheels. The horizontal gearwheel is held to the bottom of the main drive shaft by a circlip and and (usually) a spacer washer or two and this lot must be removed. You will then find that this shaft can be withdrawn vertically and the pump housing/impeller exposed. You HAVE to go this route as the main drive shaft reduces section just above the gearbox which is why you can't drag it down further.

Make sure you don't lose the little s/s pin mentioned above. Reassemble in reverse order well greasing all bolts as you go, so that future dissembly is made easier. NOTE! Be care to exactly align the brass water cooling tube that runs down the inside of the leg alongside the drive shaft. It has to locate in the rubber grommet in the pump housing exit AS YOU bring the two parts together! Not too easy.

Sorry this is such a long post, but I couldn't make it shorter!! Anyway, if you run into problems either post it here or PM me and I'll do what I can to help. I've stripped and repaired loads of these little engines (got one myself!) and once you've done the stripdown once you'll wonder why you ever went near a 'service agent'!!

Final thought! I don't know how old your engine is, but I'd be inclined to take to opportunity to clear out as many of the waterways as you can get to while it's all open.

I'm sure it'll all go well.

regards

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[jerryat]

Hi!

'two' gear wheels is, on reflection, not an exact description. The horizontal gear is 'loose' once it's removed from the main shaft, but the other forms part of the prop drive shaft and meshes with it in operation. Just thought I'd clarify in case you thought they were both 'free' wheels.

Cheers

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[Johnjo]

Hi Jerry, suspected this was the way to go via removing the prop, have already done it and had a look inside the gearbox, but decided it was better to ask, than to proceed blind !..
Good advice about cleaning out the waterways, im just wondering where all the broken off bits of the impellor are gone !
Many thanks for your very clear and easy to follow response to my post.

All the best, mike

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[steve_cronin]

Just one point on greasing screws

It is certainly a good idea to lubricate (& galvanically isolate) stainless screws from aluminium castings but put too much on and you'll be trying to compress grease into a blind hole as you tighten up. This WILL (& I've done it in the past) crack the casting around the screw holes to a very expensive degree. Just a smear is enough and preferrably on one side of the screw only (it'll work it's way around) to allow air to escape during tightening.

Steve Cronin



<hr width=100% size=1>The above is, like any other post here, only a personal opinion

 

[jerryat]

Hi Mike
You're very welcome. The 'where have the impeller bits gone' is what prompted my comment re clearing the waterways. If the engine is a few years old, I would definitely remove the head and the intermediate plate (between the block and the leg) and clear out around the cylinder 'liner' and the adjacent waterways. This is where 90% of blockages occur. Incidentally, it is much easier to fit the brass water tube from the top than the bottom (as I mentioned in the previous post) so that's an additional incentive to clear the waterways throughout.

You will need one of the 'bubble' pack service kits but these are pretty reasonably priced but do not, as a rule, include the impeller. However, all gaskets, 'o'rings etc are included, though DO check the contents list before buying as they seem to vary and you may need to get one or two bits separately! Don't ask me why they do that 'cos I haven't a clue!! Either Yamaha or Mariner packs will do as they are (except for the paint system I'm told) the same motor.

Good luck, I'm sure it'll purr like a kitten when you've finished!

Jerry

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[Johnjo]

Jerry missed your last post, was out the shed reassembling the motor after blowing out the airways with a air line. "rightly or wrongly "
Most of the broken pieces seemed to be in the bottom half, choked solid.
Anyway the good news is iv had it running in a tank and there is loads of water coming through, so all seems okay !...

All the best, mike

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[homerj]

Speaking of clearing out waterways is there any method for dissolving caked on salt. I am trying to clear some out of my outboard with very little success.

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[jerryat]

Hi!

Wish to heavens I knew of some 'additive' that would do that without damaging the interior too!! There was a thread here a week or so ago where someone suggested that one of those heavy duty radiator cleaner potions worked well. Although the context was that of diesel engines, it sounds like a very good idea to me, and I will try some through my outboard at the next lay-up and see how it works.

You may care to check the other suggestions made on the thread.

Mike, delighted your o/b is flushing copiously!! Great job!

Good sailing!

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