Running gas out of your four stroke outboard.

cubsfan · 09-23-2009, 10:15 PM

I always burn out the gas on my Honda kicker, is this necessary on a four stroke? I have heard both.

Also, I have a new Zuke 140 and it can't burn fuel out of it as it is connected to all kinds of things and the fuel line is non removable. Why wouldn't we want to burn the fuel out of our big motors?

Thanks guys.

MattPark · 09-23-2009, 10:30 PM

The fuel in a fuel injected 4 stroke doesn't have anywhere to sit and varnish/dry out like it does in a carbureted engine. Most fuel systems will hold pressure in the fuel rail for a long time, not allowing air in and bad things to happen. Fuel in the system also keeps fuel system seals happy. Some high pressure fuel pumps can be damaged by lack of fuel as well.

These engines are, for all intensive purposes, a modern automotive engine. I cant think of a single vehicle manufacturer that recommends running the fuel systems dry, ever.

bvs · 09-24-2009, 05:01 AM

Honda says you should pop the cowling off and drain the carb bowl. There's a screw for this and the gas drains out of a hose that runs outside the cowling. The directions are in the owners manual downloadable on Honda's site. I always do this if it's going to be more than a couple weeks before I use my motor again. When I bought my boat the mechanic warned me that Honda kickers have frequent carb fouling problems and stressed that the carbs can't be drained too often.

Your Suzuki, being fuel injected, won't have evaporation and varnishing issues, but you should probably drain the vapor separator tube a couple times per year.

KingSalmonBoy · 09-24-2009, 05:11 AM

I just put a new 90hp Suzuki on my boat and the dealer told me ensure the tank is full and the fuel in the tank as well as that in the engine has stabil in it when storing. My Yamaha dealer for my T8 (carb.) told me emphatically to run the fuel out of my engine left for more than a few days.

tedg · 09-24-2009, 01:52 PM

I was told that running the fuel out will ruin the injecter pump. I wouldn't want to run an injected motor dry.
Ted

cubsfan · 09-24-2009, 08:22 PM

Good info, but I am still confused. I'll look at my Honda manual and the bit about the new car comparison makes sense. Anyone else?

Thanks

Okie · 09-24-2009, 09:00 PM

For many years there has been the widespread belief that simply shutting off the fuel at the tank and then running the engine until it stops is the proper procedure before storing the engine for any length of time. Right?Wrong!
It is not possible to remove all of the fuel in the carburetor by operating the engine until it stops. Some fuel is trapped in the float chamber and other passages and in the line leading to the carburetor. the only guaranteed method of removing ALL of the fuel is to take the time to remove the carburetor and drain the fuel.

For short periods of storage, simply running the carburetor dry may help prevent severe gum and varnish from forming in the carburetor. This is specially true duriing hot weather.

This is from a repair manuel for 1978-99 Honda Outboards.

"Some of the latter engines are equiped with a drain valve you can open that will drain the carburetor."

Fuel enjection engines are treated differently.

fishkisser · 09-25-2009, 02:30 PM

I never run my carburated motors dry , but I always treat my fuel ...
I have no idea why you would want to run an injected motor dry ...
We treat all the fuel going into the Harleys and it sits for
6-8 months or more sometimes with no problems ...

bluehewes · 09-25-2009, 04:40 PM

Quote:

Originally Posted by Okie

For many years there has been the widespread belief that simply shutting off the fuel at the tank and then running the engine until it stops is the proper procedure before storing the engine for any length of time. Right?Wrong!
It is not possible to remove all of the fuel in the carburetor by operating the engine until it stops. Some fuel is trapped in the float chamber and other passages and in the line leading to the carburetor. the only guaranteed method of removing ALL of the fuel is to take the time to remove the carburetor and drain the fuel.

For short periods of storage, simply running the carburetor dry may help prevent severe gum and varnish from forming in the carburetor. This is specially true duriing hot weather.

This is from a repair manuel for 1978-99 Honda Outboards.

"Some of the latter engines are equiped with a drain valve you can open that will drain the carburetor."

Fuel enjection engines are treated differently.

My 200hp yami has a drain plug for each of the bowls, simply unscrew and your good. That's good advice if planing on storing your boat for the winter. Also fogging the carbs will keep your seals nice and soft.

If you have a carb on your four stroke yes you should run it out of fuel.

Lepper · 09-26-2009, 10:08 AM

I believe if you look in the zukie manual, it tells you how to set the motor up for long periods of storage. To fog the engine till she dies, squirt some in each cylinder, and then there is a bolt you remove to drain the fuel out of the rails. I do this every winter and have never had a problem with it starting up in the spring. I also drain the gas out of my tank completely. Started doing that when e-10 came around.

Dave

sonofacamel · 09-27-2009, 08:33 PM

I have a 2006 9.9 mercury 4 stroke outboard. What would be the proper thing to do for winter storage?

Lepper · 09-27-2009, 11:21 PM

Quote:

Originally Posted by sonofacamel

I have a 2006 9.9 mercury 4 stroke outboard. What would be the proper thing to do for winter storage?

I don't know about the proper thing to do, but what I do, is run the motor on some good stabil treated non-e-10 gas then fog the motor till she dies. Unplug everything, and drain the bowl on the carb. I also take out each spark plug and squirt some more fog stuff on each cylinder. So far everything seems to start every spring just fine. Been doing things this way since 2000.

OB1 · 09-28-2009, 12:10 PM

With my 07 Seahawk I don't run my Honda kicker dry as I use stabil at every fillup. Thought I read somewhere that the float really gets banged around with no fluid in the bowl.

Lepper · 09-28-2009, 09:18 PM

Quote:

Originally Posted by OB1

With my 07 Seahawk I don't run my Honda kicker dry as I use stabil at every fillup. Thought I read somewhere that the float really gets banged around with no fluid in the bowl.

That does seem like a really good possibility. I'll add to my above post, that this is pretty much the last thing I do before I park it for the winter.

smalldog · 09-30-2009, 12:08 PM

Carburated...run out and then pull the plugs on the bottom of the bowl.
Injected motors you do NOT run dry unless you like to pay big bucks for repairs.

Richter · 09-30-2009, 02:40 PM

Quote:

Originally Posted by smalldog

Carburated...run out and then pull the plugs on the bottom of the bowl.
Injected motors you do NOT run dry unless you like to pay big bucks for repairs.

FishRCutBait · 10-03-2009, 10:36 AM

It's very important to remember that if you ask a general question your going to get a general answer. We all have motors of different makes and month/year of production on this site and we all answer to the best of our knowledge.

To cut through the confusion go straight to your owners manual and do exactly what they say for winterizing your motors. If you don't have an owners manual you can almost always get one on the manufactures web site if you have the month and year of manufacture of your specific motor. Short of that, ask an authorized service provider with the exact year and make of your motor.

Ken Drifter · 10-06-2009, 11:41 AM

[QUOTE=fishkisser;2743618]I never run my carburated motors dry , but I always treat my fuel ...
I have no idea why you would want to run an injected motor dry ...

I have 2 Hondas (main n kicker). I have never ran them dry. I always use stabill,
they sometimes sit for 3 months and are fine.