Outboard Maintenance

[Airon]

Okay, I'm sure this has been reviewed before but couldn't find it.
I have two newer 4 stroke 115hp Yamaha's and they just passed 100hrs since last service, did leg and engine oil as well as oil filter and Racors, the manual says items such as impellers, spark plus and some other items should be done now too. What is really necessary at the 100hr interval servicing?

 

[searun]

Not unless you only put 100 hours a year on your engine. Most boat owners only put less than 100 per year. Impellers, spark plugs etc should be done each season and not at 100 hour intervals. I put about 300 per year on mine and only change up the impellers at the end of the season.

 

[Dave S]

You are supposed to change the impellers every year?

 

[scott craven]

That is overkill. As long as the water pump is working and you have a good stream of water at the telltale you are good.
All new motors have overheat alarms. If there is something wrong with the cooling system you will know.
I am going on 5 years on my last impellor change.

 

[spring fever]

That is overkill. As long as the water pump is working and you have a good stream of water at the telltale you are good.
All new motors have overheat alarms. If there is something wrong with the cooling system you will know.
I am going on 5 years on my last impellor change.

I agree with you-every 100 hours is nuts-I do mine every 3-4 years. If you followed everything on the manufacturers "to do list" you'd go broke!!!!

 

[rockdog]

Yup, I do mine every 3 years. The guys on iboats say every 2 years...but that would be for a heavily used boat.

 

[CIVANO]

for my 250 Yamaha 4 stroke the dealer said 500 hours or 5 years on the impeller

 

[JAC]

It really depends on the water you run. If I used a outboard in the Fraser all the time with dirty water I would change more often. I change mine every couple of years

 

[sly_karma]

Rebuild kits with gaskets and impeller are about $50 for most outboards. I reckon that's cheap insurance, same as clean new engine oil. Yes, modern engines have overheat alarms, but they also (mostly) have easy to access water pumps. I'd rather change an impeller before its time than have one fail when I'm out there somewhere. The alarm will sound and I can save my engine from major damage, but now I'm looking for a tow or taking a slow run home on kicker. New impellers every other year for me.

 

[Gypseas]

Don't change the impeller if it does not need it but pull the leg and clean/grease the splines at least every year

Oil on the other hand is cheap insurance

 

[searun]

Rebuild kits with gaskets and impeller are about $50 for most outboards. I reckon that's cheap insurance, same as clean new engine oil. Yes, modern engines have overheat alarms, but they also (mostly) have easy to access water pumps. I'd rather change an impeller before its time than have one fail when I'm out there somewhere. The alarm will sound and I can save my engine from major damage, but now I'm looking for a tow or taking a slow run home on kicker. New impellers every other year for me.

x 2, way cheaper to do preventive maintenance than pay the price when an impeller fin breaks loose and lodges in your power head. I also run off shore a lot. There is a lot of cavitation going over big waves. That lessens the service life of the impeller in my opinion, so I would rather change them than worry about the consequences of trying to cheap out.

 

[Aces]

x 2, way cheaper to do preventive maintenance than pay the price when an impeller fin breaks loose and lodges in your power head. I also run off shore a lot. There is a lot of cavitation going over big waves. That lessens the service life of the impeller in my opinion, so I would rather change them than worry about the consequences of trying to cheap out.

Every spring we pull the legs to grease the splines and change the impellers

 

[scott craven]

Running offshore in guide boat operations puts a lot of hours on those motors. I would guess approx 50-60 hours a week.
The average guy runs his motors 100 hours a year.
we are not really looking at a fair comparison.
keep in mind the question was not directed at commercial operation's