Flushing Mariner 2.5hp 2 stroke outboard

Hypocacculus

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We've just acquired a 1996 Mariner 2.5hp 2 stroke outboard for our tender. It's our first outboard and in virtually new condition so we want to look after it proper, like . So we are making our first forays into flushing. Our experiments in our wheelie bin suggest that we will end up with water everywhere if we try to do it in our boat's cockpit with a bucket; we don't want to have to remove the prop every time, we've abused the split pin enough replacing the impellor. The outboard is too old (we think) to have the thread so that a flushing attachment can be used. Does anyone know of any sneaky diy or aftermarket method of flushing through with a hose that doesn't involve getting soaked? Can it be done without running the engine?
 
I have one. One boatyard (Evros in Leros) used to have metal bins which were just right for clamping the engine to. After they got fancy new plastic bins I took to running it on the pushpit with a bucket hung over the shaft, being fed with a hose. Extremely messy, but did the job.

I also use 'fogging oil' when laying up.
 
flushing

We've just acquired a 1996 Mariner 2.5hp 2 stroke outboard for our tender. It's our first outboard and in virtually new condition so we want to look after it proper, like . So we are making our first forays into flushing. Our experiments in our wheelie bin suggest that we will end up with water everywhere if we try to do it in our boat's cockpit with a bucket; we don't want to have to remove the prop every time, we've abused the split pin enough replacing the impellor. The outboard is too old (we think) to have the thread so that a flushing attachment can be used. Does anyone know of any sneaky diy or aftermarket method of flushing through with a hose that doesn't involve getting soaked? Can it be done without running the engine?

Try using an ordinary builders' bucket. Just hold the engine upright, resting on the bottom of the bucket. This sounds scarey, but it works quite well, for the short time you are likely to run the engine. The restriction of the water movement reduces the splashing - at low revs, naturally. Try to keep the prop away from the sides of the bucket!
 
The prop is so easy to remove and replace, I would advise never flushing it in a bucket or bin with the prop on. You may consistently get away with it but it remains an easily avoided risk.
Morgan
 
...we've abused the split pin enough replacing the impellor...

Get a (in fact several) new ones sooner rather than later, they cost pence and save the aggravation we had a few years back of snorkelling all around a fortunately shallow & clean Greek anchorage for two hours to find/recover the prop from a friends Mercury - we were quite amazed at just how far away from the dinghy's location it had 'spat' the propeller - whose split-pin had let go.

Re the original post; we too go for the hang outboard on the pushpit bracket, suspend a big bucket under/around the leg, fill with fresh and soapy water, then leave it running for half an hour, topping up the bucket as necessary; we don't put it in gear though, on the couple of occasions we've tried that, the buckets split - perhaps we need better quality buckets?
 
... we don't put it in gear though, on the couple of occasions we've tried that, the buckets split - perhaps we need better quality buckets?
Unfortunately, the Mariner/Mercury 2.5 2 stroke doesn't have gear lever :(
 
Unfortunately, the Mariner/Mercury 2.5 2 stroke doesn't have gear lever :(

Exactly. I was hoping we could get away from the whole spinning prop thing. Reading around, it seems that forcing water from a hose through the engine when it is off should swill things out nicely. As far as I can tell, newer engines have threaded the coolant outflow to allow an adaptor to screw on a hose directly; Examination of ours shows that the outflow has a hole that would be nicely blocked by something about the size of a wine cork so it seems that with a bit of ingenuity, something could be fixed to a hose and wedged in the hole. If somebody has actually done this, I'd love to hear about it. Otherwise I'm in the terrible position of having to invent something myself. :eek:
 
We had a hose attached to the threaded the coolant outflow, and had a 12 pump attached to the end of the hose. 12 v pump in a bucket of water, engine rinsed.

Not sure about the soap in the above post!
 
Well, you could just take it home whenever you can and flush it properly.

Every couple of years easy enough to remove the head and clean it out if it needs it.
 
Unfortunately no use to those with outboards without a gearbox but I have an interesting solution for those whose engines can run in neutral. Cut the top off an old fender large enough to fit over the prop and cavitation plate. Cut a couple of holes in the new rim, I found a large wad punch the best, about an inch diameter seems to work well. Tie a length of rope through each hole, tie that over the outboard or to the pushpit after slipping the fender over the outboard leg. Fill with fresh water and run the engine, preferably with a hose pipe running throughout.

The beauty of this is that there is sufficient depth of water to ensure that it is being pumped through the engine, exhaust noise is minimised and the fender can be stowed rolled up afterwards. Making the holes smaller lets the rope cut through the soft plastic.
 
Well, you could just take it home whenever you can and flush it properly.

Ah yes. drag engine to car and cram in with all the other boat $h!t. Drive home with petrol fumes because we didn't run the carb dry. Empty recycling out of wheelie bin. Fill wheelie bin with water via hose pipe. Install engine and flush, thus disturbing our neighbours quiet evening. Remove bit of shredded paper that blocks tell tale. Rearrange bicycles and motorbikes in overcrowded garage so engine can be installed to drain on wobbly, seatless chair because we haven't a bracket for it yet. Struggle with wheelie bin to end of drive, to tip up and empty in gutter; hope it survives impact. Change shoes and socks because I failed to jump the wave. Replace all recycling in bin. Next weekend, cram outboard in car with all our other boat $h!t and find that not all the petrol has evaporated yet. Drag down to pontoon from carpark...

Forgive me for being unreceptive to your suggestion which is a valid one but we think our (admittedly disorganised) Sunday nights, what with putting the boat to bed, driving two hours home, scavenging some sort of dinner from the back of the fridge, consoling the cat and ironing tomorrow's shirt contain enough joy already.
 
Ah yes. drag engine to car and cram in with all the other boat $h!t. Drive home with petrol fumes because we didn't run the carb dry. Empty recycling out of wheelie bin. Fill wheelie bin with water via hose pipe. Install engine and flush, thus disturbing our neighbours quiet evening. Remove bit of shredded paper that blocks tell tale. Rearrange bicycles and motorbikes in overcrowded garage so engine can be installed to drain on wobbly, seatless chair because we haven't a bracket for it yet. Struggle with wheelie bin to end of drive, to tip up and empty in gutter; hope it survives impact. Change shoes and socks because I failed to jump the wave. Replace all recycling in bin. Next weekend, cram outboard in car with all our other boat $h!t and find that not all the petrol has evaporated yet. Drag down to pontoon from carpark...

Forgive me for being unreceptive to your suggestion which is a valid one but we think our (admittedly disorganised) Sunday nights, what with putting the boat to bed, driving two hours home, scavenging some sort of dinner from the back of the fridge, consoling the cat and ironing tomorrow's shirt contain enough joy already.

Don't know how people cope with boating really.....:)
 
How about getting a fishermans bait bucket.
They can be got in bigger sizes than the normal 2 gallon household size, (some are rectangular) and they have a plastic lid which you could cut to fit around the OB leg to reduce the amount of water splashing out. Try an ebay search.

Bill
 
How about getting a fishermans bait bucket.
They can be got in bigger sizes than the normal 2 gallon household size, (some are rectangular) and they have a plastic lid which you could cut to fit around the OB leg to reduce the amount of water splashing out. Try an ebay search.

Bill

It's an idea... but I'm still hoping for a solution with the hose that doesn't involve running the engine though. Think of the convenience: Quick hose of boat, fill up water tank, whack on attachment, five minutes up the outboard 'ole in situ on the pushpit and we'd be done without all that faffing and whirling of blades. An impossible dream?
 
It's an idea... but I'm still hoping for a solution with the hose that doesn't involve running the engine though. Think of the convenience: Quick hose of boat, fill up water tank, whack on attachment, five minutes up the outboard 'ole in situ on the pushpit and we'd be done without all that faffing and whirling of blades. An impossible dream?

Modify it by drilling and tapping a hole into which a hose tail fitting can be screwed (or a plug when in use) like newer versions of the same engine have.

I think it may be possible although not 100% sure
 
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