Tips to starting up an old outboard boat engine that has been sitting?

Blaze

Blaze

The Jeeper Reaper
Joined
Aug 9, 2005
Location
Wake Forest, NC
So my son found an old boat in my neighbors yard. It's an old 13ft DuraNautic. All aluminum and in really good shape but disgusting. Guy said it has been sitting for 3 years but I feel like it has been longer. Trailer tags say 2018 so he might be right. It has a Yamaha 6 outboard that surely hasn't run since then. I know it is a 2-stoke, so from what I am seeing people are saying 50:1. I know the usual, oil the cylinders, turn it over a couple times, clean the plugs and let it rip.

But this is the first boat we've ever had. I know someone said to replace the impeller before starting it so you don't get dried rubber in the cooling system. I remember someone telling me once about starting a boat motor in a bucket or tub of water or something.

Any advice here? In less than one day my boys have cleaned it up to the point of a pressure wash and I ordered new carpet and all for it today.

Pic of him dragging it home. Check out the trees growing out of it. :lol:

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google: outboard earmuffs

that is all you need with a water hose.

but yes check everything for dry rot
 
Yes, definitely replace the impeller. You don't know the condition of it, and if it's of any age then it can harden and take a "set" and then won't pump water properly. Also, if it's been dry for a while the rubber can get stuck to the housing and tear chunks off when it gets rotated again. Either way, you might not have cooling water flow. An impeller and housing kit is cheap.

Not a bad idea to replace the fuel filter either. Check that the primer bulb is not dry rotted. Also check for signs that the hose between the bulb and engine is not collapsing (when engine running), which can mean a problem with the check valve in the bulb. And cause fuel problems. Again, cheap to replace if needed.

It's probably going to be 50:1, but if it's a Yamaha then it may be 100:1. No harm in doing 50:1 though, and make sure you use a proper Outboard/Marine TCW3 oil.
 
BRUISER said:
google: outboard earmuffs

that is all you need with a water hose.

but yes check everything for dry rot
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Well hot damn, that's what that thing was we found in the boat. Guess we already have the earmuffs!

Fabrik8 said:
Yes, definitely replace the impeller. You don't know the condition of it, and if it's of any age then it can harden and take a "set" and then won't pump water properly. Also, if it's been dry for a while the rubber can get stuck to the housing and tear chunks off when it gets rotated again. Either way, you might not have cooling water flow. An impeller and housing kit is cheap.

Not a bad idea to replace the fuel filter either. Check that the primer bulb is not dry rotted. Also check for signs that the hose between the bulb and engine is not collapsing (when engine running), which can mean a problem with the check valve in the bulb. And cause fuel problems. Again, cheap to replace if needed.

It's probably going to be 50:1, but if it's a Yamaha then it may be 100:1. No harm in doing 50:1 though, and make sure you use a proper Outboard/Marine TCW3 oil.
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The line and bulb don't look great. I'll probably go ahead and replace the lines and bulb along with the filter and impeller and housing kit. The boat came with extra oars but rather not have to use them. :lol:
 
either m
Blaze said:
Well hot damn, that's what that thing was we found in the boat. Guess we already have the earmuffs!



The line and bulb don't look great. I'll probably go ahead and replace the lines and bulb along with the filter and impeller and housing kit. The boat came with extra oars but rather not have to use them. :lol:
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dont use the cheap atwood/walmart fuel bulbs.
 
Also, FYI places like West Marine are very expensive and usually only stock aftermarket equivalent parts (not OEM). If you don't need it today, try Crowley Marine, iBoats, and Boats.net for OEM parts, I think they all have parts blowups. There are many others too. I far prefer buying something OEM (the fuel bulb/line is a very good example) at online prices instead of getting a generic equivalent at West Marine, etc.
I mostly buy Evinrude parts, so I'm not as versed in the Yamaha suppliers, but I'm pretty sure all the places I've listed above also stock OEM Yamaha.
Crowley shipping is cheap and fast, even though they're in Colorado.
 
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Water pump impeller has already been covered, but remember water flowing when using muffs does not equal water flowing when in the water. Your hose pressure flows water with muffs even if the water pump is not functioning properly. That's why its a good idea to run it in a bucket anyway, or make sure to check that it's "peeing" when put in the water.

Made that mistake once as a teenager...
 
LBarr2002 said:
Water pump impeller has already been covered, but remember water flowing when using muffs does not equal water flowing when in the water. Your hose pressure flows water with muffs even if the water pump is not functioning properly. That's why its a good idea to run it in a bucket anyway, or make sure to check that it's "peeing" when put in the water.

Made that mistake once as a teenager...
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Yep, that's why the "pee" stream water outlet is called a telltale.
 
The impeller piece is the only part that is different that any other two stroke motor.

I've done the barrel and the muffs. Both work for starting it in the yard.

Do not put it in gear or rev it up. It should start without either of those two things. I only put it in gear or rev the motor when it is in the water.
 
That's a cool looking little boat. SIM Yamaha is a great site for finding parts off of the part diagrams. ABSOLUTELY change the water pump assembly out before starting it. I just got to rebuild my 250HP Yamaha due to a failed impeller. Change out the lower unit oil before running it too. Go with OEM yamaha for the fuel bulb and filters. Carry spares. Yamaha should be 50:1 on the oil mix and use TC3W or whatever it is. Depending on how old the outboard is, it may have a flushing hose on the bottom side of the cowling. You can run it with the hose hooked to that instead of muffs.
 
Do NOT use starting fluid (Ether) on a 2stroke, it’s too violent and can break the rings or worse (just so you’re aren’t tempted)

mix the gas a little heavy the first tank (40:1) just so you know you have enough oil, it’ll smoke a little, but once you get the right mix in it it will clean up.
Those quart cans of TruFuel may be the better thing to go with, you don’t have to mess with mixing right away and it’s better fuel than what you’re getting from the pump and should help with the start up process and help clean things out.
 
Well, we replaced the impeller and did the usual things and it fired up. Only ran for a few seconds and then died. Going to play around with it a little more, but the guy we got it from said "it needed a new pump" which I am wondering if he meant fuel pump now.

I think I am also going to have to clean out the cooling system. Maybe we didn't run it for long enough to get it to pump water, but there was no water out the weep hole. The old impeller housing was full of junk and I had to clean it out pretty good. I might get a new one to replace it because it was rough.
 
Blaze said:
I think I am also going to have to clean out the cooling system. Maybe we didn't run it for long enough to get it to pump water, but there was no water out the weep hole. The old impeller housing was full of junk and I had to clean it out pretty good. I might get a new one to replace it because it was rough.
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It will need to run for more than a few seconds to get it pissing, but definitely check the piss hole ... notorious for getting dirt daubers/spider nests in them
 
Blaze said:
Well, we replaced the impeller and did the usual things and it fired up. Only ran for a few seconds and then died. Going to play around with it a little more, but the guy we got it from said "it needed a new pump" which I am wondering if he meant fuel pump now.

I think I am also going to have to clean out the cooling system. Maybe we didn't run it for long enough to get it to pump water, but there was no water out the weep hole. The old impeller housing was full of junk and I had to clean it out pretty good. I might get a new one to replace it because it was rough.
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next time you fire it up stick a coil wrapped guitar string up the tell tale and fish it in and out, the water will flush it out.I have to put tape over mine or some bug plugs it up w mud.
 
Blaze said:
Well, we replaced the impeller and did the usual things and it fired up. Only ran for a few seconds and then died. Going to play around with it a little more, but the guy we got it from said "it needed a new pump" which I am wondering if he meant fuel pump now.

I think I am also going to have to clean out the cooling system. Maybe we didn't run it for long enough to get it to pump water, but there was no water out the weep hole. The old impeller housing was full of junk and I had to clean it out pretty good. I might get a new one to replace it because it was rough.
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There's so little cost difference between the impeller itself and the kit with the impeller cup, impeller, shaft key, gaskets, etc, that I always replace the cup (housing) at the same time. Depends on where the outboard is used though; if it's in river or saltwater the silt/sand/debris will scar up the cup. It's one of those many things that you might as well replace while you're in there, because you're already doing 90% of the work just to access and replace the impeller. Get the OEM kit, not aftermarket.
 
Fabrik8 said:
There's so little cost difference between the impeller itself and the kit with the impeller cup, impeller, shaft key, gaskets, etc, that I always replace the cup (housing) at the same time. Depends on where the outboard is used though; if it's in river or saltwater the silt/sand/debris will scar up the cup. It's one of those many things that you might as well replace while you're in there, because you're already doing 90% of the work just to access and replace the impeller. Get the OEM kit, not aftermarket.
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Yeah, I should have just done that. I'll probably get the whole kit and just replace it all again just to be sure. It was only used in freshwater, but it was nasty still.
 
So I got the engine running again and kept it running with a bottle of gas. The water started pumping out of the weep hole just fine. I think it must be the fuel pump. I guess that's what the old guy meant by "it needs a pump"
 
Blaze said:
For anyone who knows these things, it is a 6MSHT.
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Tiny! 6HP of 1995 fury, according to Google.

Blaze said:
So I got the engine running again and kept it running with a bottle of gas. The water started pumping out of the weep hole just fine. I think it must be the fuel pump. I guess that's what the old guy meant by "it needs a pump"
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It's a pulse-diaphragm pump (so says the exploded parts view), so the common problems are deteriorated diaphragms and rusted/broken check valve plates. If they got old, or if it backfired, the diaphragms are torn.
Should be cheap and easy to rebuild, if the pump is actually the problem.

Yamaha Outboard Parts by Year 1995 OEM Parts Diagram for CARBURETOR | Boats.net

All the parts on the bottom right (#26-35) are the fuel pump assembly. Should only need a few of those parts to rebuild. Really the only moving parts are the two check valves and the two diaphragms; the rest is just gaskets and hardware.

Don't forget the fuel strainer if it's not already replaced.
 
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Fabrik8 said:
Tiny! 6HP of 1995 fury, according to Google.



It's a pulse-diaphragm pump (so says the exploded parts view), so the common problems are deteriorated diaphragms and rusted/broken check valve plates. If they got old, or if it backfired, the diaphragms are torn.
Should be cheap and easy to rebuild, if the pump is actually the problem.

Yamaha Outboard Parts by Year 1995 OEM Parts Diagram for CARBURETOR | Boats.net

All the parts on the bottom right (#26-35) are the fuel pump assembly. Should only need a few of those parts to rebuild. Really the only moving parts are the two check valves and the two diaphragms; the rest is just gaskets and hardware.

Don't forget the fuel strainer if it's not already replaced.
Click to expand...

Thanks, just ordered the parts. I am betting that it is the problem, if I keep the engine running by squirting gas down its throat it runs fantastic. I guess technically it could be the float or something, but considering how it is acting and what the guy told me I figured it is worth a shot. With it being a 1995 it probably can't hurt anyway.
 
So I am at a standstill here. I replaced the fuel pump plates and diaphragm and took the carb apart and cleaned it. I put it back together and it started and idled but then as soon as it started pushing water out if the weep hole it bogged and died. Now it won't run for more than a couple seconds again if I pour gas down its throat. It also looks like a bunch of oil leaked out of the prop shaft, too. When I lifted the prop out of the water it puked all kinds of oily water out into my bucket.

Trying to figure out if it is worth putting much more time and money into a 6hp engine or just start looking for a bigger engine.
 
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