impeller replacement

[Rizzo]

So after some advice from members here...I purchased a 2 stroke 8 hp engine (nissan) Conveniently the guy selling it had forgotten the gas tank at the marina so we could not test the motor. I trust him and buy it anyways. Now with gas tank in hand and engine in my garage I decide to fire it up with the muffs on. After a few seconds it shuts off and I notice no water peeing out. This happens a few times. Runs a few seconds (five?) then shuts down. I imagine this is a safety feature? Motor shuts off after a few seconds to prevent overheating? Anyways, not wanting to push my luck...I decide changing the impeller might be my best option. Been watching some youtube videos and feel I could probably do this myself if I can find the parts. Having said that, would prefer a "pro" to do it if price is reasonable. Anyone know what an impeller would cost (just the part), and then what it would cost (parts included) to have a marina do the work? The reason I am debating getting a marina is in case I am wrong...perhaps no water peeing is not due to faulty impeller. Any thoughts?

Edited April 20, 2017 by Rizzo

[buick14]

Hey

That is a very solid motor. Check for blockages in the pee-hole first. Junk can get caught up and cause issues.

Impellers are not expensive to purchase (think I paid $25 for a 60hp Nissan) and should be changed every so often depending on environment etc. It's not a difficult task either if you decide to do it yourself.

You have a nice motor there, don't feel soured just yet...

Also 4-5 seconds might not be enough for the water to travel in and out of the telltale ...so maybe there is some switch or cut-off you need to disengage or adjust once the motor is turned over..

Edited April 20, 2017 by buick14

[DRIFTER_016]

Any time you buy a used OB it's best to do an impeller replacement.

As for it stalling it sounds like you may have an air leak in the fuel line, bulb or connectors.

[Rizzo]

Buick - did see that on youtube too...I may try again tomorrow but disconnect the rubber hose up in the motor and see if I can get water out that hole...then I know problem is a blockage not impeller.

 

Drifter...after I decided I didn't want to ruin the motor...I did notice a hole in gas line...I had gas peeing out of the line but no water peeing from motor! Could this be enough to stall the motor? It is a pin hole but there was a stream of gas shooting out.

[OhioFisherman]

https://www.nissanoutboardparts.com/Parts-Books.html

 

 

https://www.amazon.com/3B2-65021-1-18-8920-Impeller-Tohatsu-Outboard/dp/B016U42W5K

 

 

The impellers are pretty cheap?

[chris.brock]

 

I don't think it's stalling because of the impeller/ cooling system not functioning properly. If there was an overheating safety feature (I don't think there is anyways) it wouldn't kick in that quick. Like Buick said, there is a few seconds delay before it starts peeing out water. It sounds like it's starving for fuel.

 

I wouldn't worry about the cooling system right now, just try to get it running first. JMO

[Rizzo]

so sounds like deal with the stalling first...maybe the pinhole in fuel line is enough of a problem? sucking air? Think maybe I can just cut a segment off the fuel line, the leak is near the end anyways. As long as I can re-attach the fuel connector thingy to the exposed cut hose. I imagine it just slides into the hose and then tighten some clamp around it.

[OhioFisherman]

I had to replace the hoses on my 35 hp merc because of a pin hole in them, it doesn't take much.

[DRIFTER_016]

Drifter...after I decided I didn't want to ruin the motor...I did notice a hole in gas line...I had gas peeing out of the line but no water peeing from motor! Could this be enough to stall the motor? It is a pin hole but there was a stream of gas shooting out.

 

Definitely!!!!!

[chris.brock]

 

May as well fix it first for sure, easy fix, but there should be enough gas in the line and carburetor bowl to run for more than 5 seconds. That's probably not the big problem. Tightly wrap some electrical tape around the hole if you feel like tinkering around tonight to test that.

[ecmilley]

Use s pin or small pick nail ect to clean.out the hole.

Hole in line will cause issues. While running continue to squeeze primer bulb see if it stays runnin check.vent blockage in tank possible fuel pump diaphram.

About 1hr labor to change.an impellor

[chris.brock]

 

When it does run for the initial 5 seconds does it idle nicely or are you blipping the throttle and fighting to keep it running?

[Old Ironmaker]

I strongly suggest anyone that owns a boat join iboats.com. There is a good group of experts there that I have learned a lot from. You have been given all good info here.

 

I would run a weed whacker line up the overflow tube, all sorts of things can get lodged in there from algae to insects.

 

Don't forget the water to the outboard needs to get up in temp before it opens. 5 seconds isn't long enough, especially with cold water from the hose this time of year.

 

A leak in the fuel line will stop the engine, as suggested pump the bulb while it is running then cut the end off and put a new hose clamp on as you were going to do.

 

I know of guys here that have never changed the impellor after 20 years or more. Mine was 30 bucks for my 115HP Mariner. I would expect an hours labour from a Marina mechanic. It should take a pro less than an hour. Call and ask.

 

You may have a bad primer bulb, happened to me last year, the one I had only lasted 3 years.

 

Make sure the arrow from the fuel line bulb is pointing to the engine, yes I did just last year when I changed a cracked bulb and that cost me 90 bucks for a marina to tell me. I had a new line and it was too long so I looped it and thought the bulb was pointing in the right direction, wrong. The engine actually started by pumping the bulb and ran well then stalled at 2000 RPM. Being in a rush cost me 100 bucks.

 

Change the fuel filter while you are at it. It can be plugged too.

 

Join iboats.com

 

Best of luck, buy a new to you motor and it won't run sucks big time. A lesson to us all about buying without running it, at least with the muffs on. Even the thing may idle great in the driveway and won't run under load. Found that out last year when buddy swapped out his 350HP Mercruiser only to find it stalled at 3000 RPM.

 

To anyone, what is the proper name for muffs? Sometimers moment.

Edited April 20, 2017 by Old Ironmaker

[OhioFisherman]

It seems to be motor or engine flusher Old.

[Freshtrax]

Location? If near kitchener You could bring it here or I could pop buy and look at it. I don't think the motor is stalling due to impeller. Likely a fuel issue. Impeller can me done in an hour or less.

Edited April 20, 2017 by Freshtrax

[wallyboss]

I had an issue with a borrowed motor one year. 20 hp Merc 2 stroke. I tried it at home in a barrel before heading out for a fishing trip and it wouldn't pee water out and it got pretty warm. So i gave the guy a call and he said to make sure to give it some throttle to bring up the RPM's. So I went back out and tried that and as soon as I did that the water started peeing out. Might want to try that if you can get to idle long enough. But sure doesn't sound like it's a cooling issue that shuts it down.

Edited April 20, 2017 by wallyboss

[Fisherman]

Another point, sometimes the water muffs don't seal tight enough on the intake to get the water up to the impeller. If you have a clean garbage can, (or put a plastic bag in dirty garbage can) and fill it above the cavitation plate as a minimum. There's no way it will auto shut off after five seconds from lack of cooling on start up.

[misfish]

Could also be a sticky needle valve in the carb.

[Old Ironmaker]

You can 50 buck yourself to death trying to self diagnose a problem, plugs, wires, fuel line, bulb, fuel filter, power pack, and, and. I might spend the $100.00 and take I into a marine mechanic and get a definitive cause and a quote then DIY.

[Sinker]

Pull the choke when it starts to stall and see what happens.

 

S.

[wkrp]

fresh gas and seafoam

[Rizzo]

well gonna get some fresh gas, seafoam, cut the gas line where the leak is and reattach...then see what happens! I did speak to former owner today...he claims this motor has an internal thermostat (I know some engines do) so don't be surprised that it doesn't pee right away.

[chris.brock]

I thought outboards with thermostats pee right away but the water doesn't flow through the power head until it's up to temp? Did Nissan do things differently?

 

good luck though, keep us posted

Edited April 20, 2017 by chris.brock

[DRIFTER_016]

I thought outboards with thermostats pee right away but the water doesn't flow through the power head until it's up to temp? Did Nissan do things differently?

 

good luck though, keep us posted

 

Most but not all.

Have seen some that don't pee until they are warm.

My little 4hp Merc 2 stroke is like that.

[Rizzo]

oh man my wife is ticked....and I am not happy either. Got the fresh gas, got the seafoam, cut the piece of hose out that had a pinhole leak, reattached gas fitting....very excited....NOTHING. couldn't even get a sputter tonight. Now I am stumped. Forget the impeller, I can't even get this thing to turn over. I did pull the plugs...how wet should they look? I couldnt tell if they were even wet at all. They certainly didn't look soaking wet...should they?