Proper shutdown at end of day

[Skidz]

Been reading several posts here where people say to run the OB out of fuel at the end of the day. On my 2 stroke, is this still advisable? M40C. After reading many posts on the subject in other forums, it seems the general consensus for 2 strokes at least is NOT to run them out of fuel. By doing so, you are subjecting the internals to a few revolutions without any lubrication. And I will say, that makes sense to me. I have been running my Johnson OB the past several years, and now my Tohatsu, and never running them dry. I do make sure to have a bit of Seafoam and Stabil in every tank. And I have had zero issues. I would like to see what the consensus is here.

If there is a reason why to run the fuel out, can you explain it? And, it is my understanding that even doing this, there is still fuel left in the bowl; is this assumtion correct?

Thanks!
Skidz

 

[CaptainKickback]

Re: Proper shutdown at end of day

I've seen some say not to run a 2 cycle empty but that's with a VRO that could keep pumping oil.

I have a 15 hp Evenrude for my dinghy. Before I take it off and lay it in the back of the SUV, i run it dry so there is no gas in the float chamber when I lay it down. Had a Johnson 225 with a VRO and never ran it dry. No problems with either motor.

 

[pvanv]

Re: Proper shutdown at end of day

Today's US fuels are so poor that they leave terrible varnish deposits as they evaporate. Because of that, you cannot leave fuel sitting in the carb for more than a couple of days. So, if not using the motor tomorrow, it is best to get the gas out. You can run it out, or you can open the drain screw and drain it out. It's a wives tale that running a 2-stroke out will result in no lubrication. The motor will stall long before the crankcase is completely devoid of fuel mix, and in any event, the oil in the mix will remain in the bearings for quite a while. If running dry, there will be maybe a half-teaspoon of gas in the bottom of the carb bowl, where evaporation will not leave varnish in a critical location. Additives such as stabilizers will help to keep the fuel from rotting prematurely, but do nothing to eliminate the deposits that remain when it evaporates.

When we winterize and store OB's, we run them out, and then blow out the fuel lines, and open the carb drains to get the vast majority of fuel out. We do seasonal storage of dozens of motors a year, both 2- and 4-strokes. Once upon a time, it was possible to store the motors with the carbs "wet", but that is no longer the case. The longer the motor sits, the worse the varnishing. The magic number is about 1 or 2 weeks. After that, expect varnishing to some extent if the carb was not empty.

 

[CaptainKickback]

Re: Proper shutdown at end of day

Pvanv, since you are talking about the gas and not the oil, it would seem your advice applies to any carburated engine, 2 or 4 stroke, I/O or OB. Am I reading that right?

 

[pvanv]

Re: Proper shutdown at end of day

Correct. Even your rototiller, lawn mower, pressure washer, and snow blower.

 

[Skidz]

Re: Proper shutdown at end of day

Paul,

Thanks much for the explanation. Since my boating days are pretty much over this year, I'll put the OB in a tank and run it out this weekend.

 

[KDAVID1]

Re: Proper shutdown at end of day

Today's US fuels are so poor that they leave terrible varnish deposits as they evaporate. Because of that, you cannot leave fuel sitting in the carb for more than a couple of days. So, if not using the motor tomorrow, it is best to get the gas out. You can run it out, or you can open the drain screw and drain it out. It's a wives tale that running a 2-stroke out will result in no lubrication. The motor will stall long before the crankcase is completely devoid of fuel mix, and in any event, the oil in the mix will remain in the bearings for quite a while. If running dry, there will be maybe a half-teaspoon of gas in the bottom of the carb bowl, where evaporation will not leave varnish in a critical location. Additives such as stabilizers will help to keep the fuel from rotting prematurely, but do nothing to eliminate the deposits that remain when it evaporates.

When we winterize and store OB's, we run them out, and then blow out the fuel lines, and open the carb drains to get the vast majority of fuel out. We do seasonal storage of dozens of motors a year, both 2- and 4-strokes. Once upon a time, it was possible to store the motors with the carbs "wet", but that is no longer the case. The longer the motor sits, the worse the varnishing. The magic number is about 1 or 2 weeks. After that, expect varnishing to some extent if the carb was not empty.

Does E fuel leave the varnish as well?

 

[oldman570]

Re: Proper shutdown at end of day

E fuel seams to be worse according to the following,
http://www.fuel-testers.com/e10_gas_not_safe_for_marine_engine.html
Read for yourself, and you deside.
Have fun and Be Safe

Oldman570

 

[pvanv]

Re: Proper shutdown at end of day

Does E fuel leave the varnish as well?

Yes. After all, it's still 90% regular gas. E-10 also has other problems, relating to how much the alcohol attracts water, how corrosive that mix can be, and the solvent action of the alcohol on plastic and rubber in the fuel systems.

 

[CaptainKickback]

Re: Proper shutdown at end of day

I've had 3 boats and none of them had fuel shut offs. Has this fuel issue just recently become a problem? Does running the engines clean the buildup? Any problem with fuel injection? Does the gas purchased on the water have the same problem?

Sorry for so many questions. But this issue seems a bit too much to ignore.

 

[pole position]

Re: Proper shutdown at end of day

I always run the fuel out of my outboards,1973 50 Evinrude,2005 Nissan 5,? 1.2 Tanaka and have 0 fuel problems with any of them.

 

[TOHATSU GURU]

Re: Proper shutdown at end of day

Fuel evaporation has always been an issue. However, it has become critical due to the smaller jets and orifices found in todays engines. It's a EPA caused problem

 

[pongy]

Re: Proper shutdown at end of day

What about motors like the TLDI, Often thought about this but not sure if to run it dry or not

 

[TOHATSU GURU]

Re: Proper shutdown at end of day

No carbs. Closed fuel system. But, if you plan to leave the engine for over a month without running it. Drain the fuel system.

 

[pvanv]

Re: Proper shutdown at end of day

I've had 3 boats and none of them had fuel shut offs. Has this fuel issue just recently become a problem? Does running the engines clean the buildup? Any problem with fuel injection? Does the gas purchased on the water have the same problem?

Sorry for so many questions. But this issue seems a bit too much to ignore.

All carbed 4-strokes should have the fuel line disconnected at the motor at the end of the day. This helps prevent fuel dilution of the oil, and possible damage to the fuel pump diaphragm due to pressurized fuel tanks due to solar heat-up. That's a good time to run it dry.

Gasoline is not an aggressive-enough solvent to clean the passages. Fuel injected motors have sealed systems, so they don't suffer as fast, but the gas will still rot after a month or so.

US Marina fuel is typically just pump gas, with a "value added" price for the convenience of fueling-up on the water. So it has the same issues.

 

[MH Hawker]

Re: Proper shutdown at end of day

I was under the impression that marina gas dose not have the alcohol and dosnt absorb water like E 10 and is a bit more stable before it breakes down.

 

[pvanv]

Re: Proper shutdown at end of day

I was under the impression that marina gas dose not have the alcohol and dosnt absorb water like E 10 and is a bit more stable before it breakes down.

Not necessarily. Check the pump. In the US, you will likely find a sticker that says something like "Contains up to 10% Ethanol". If so, it will be regular pump gas, just like from the gas stations where we fill our cars. If they have non-ethanol, they will usually advertise that fact, and proudly charge you extra accordingly.

 

[MH Hawker]

Re: Proper shutdown at end of day

Yes exactly, but I wasnt aware that marinas were now selling the E 10, the ones around here on the lakes and rivers have the non-Ethanol, and ooo yes it costs at least plus .75 more per gallon, but thats what I run in my boat its kept at a marina and for me its just simpler to fill up there and I use the 6 gal tanks so its not that much. Thier is only one local fuel company that has the non-Ethanol and its close enough that I could pick it up there at a savings but I dont. the lake I run is a limited HP lake and the fuel cost is low compaired to most. And it may be that non-Ethanol gas is getting harder to find and why the E 10 is showing up at marinas.

 

[Sea Rider]

Proper shutdown & Ethanol issues

Proper shutdown & Ethanol issues

Been a run carb dry after each use fan for many years, as I boat constantly never really needed a exhaustive carb clean because of oil gunk formation inside carb. Simply there was no gunk to clean. Thought that this was key to trouble free operation until recently my 2 stroke 18 horse started to missfire at wot, removed carb from engine and dismantled into pieces. What found at only 100 metered worked hours really shocked me, a heavily white stuff clog between gas pump outing and carb bowl passage. The carb interior and fuel check valves were impeccable, no need to clean, just the horrible clog itself.

Seems engines that has attached gas pumps to carb's bodies like 5, 9.8, 15, 18 Hp are more prone to suffer passages clogs than carbs that have separate fuel pumps as in bigger engines. What find strange is that the white powder like stuff by passed internal tank filter, carb filter and pump's check valves. No problem was found whatsoever with standard gasolines untill we switched to E8, so E is the direct cause to blame for.

Has anyone had similar problems ? Alwayrs run fresh fuel and consume mostly all at the end of our boating day and top with fresh fuel on next constant outing. Does anyone knows if a water separator fuel filter will get rid of the white stuff ? if so, will consider to place one to avoid future constant carb cleaning.

Happy Boating

 

[pvanv]

Re: Proper shutdown & Ethanol issues

Re: Proper shutdown & Ethanol issues

Been a run carb dry after each use fan for many years, as I boat constantly never really needed a exhaustive carb clean because of oil gunk formation inside carb. Simply there was no gunk to clean. Thought that this was key to trouble free operation until recently my 2 stroke 18 horse started to missfire at wot, removed carb from engine and dismantled into pieces. What found at only 100 metered worked hours really shocked me, a heavily white stuff clog between gas pump outting and carb bowl passage. The carb interior and fuel check valves were impeccable, no need to clean, just the horrible clog itself.

Seems engines that has attached gas pumps to carb's bodies like 5, 9.8, 15, 18 Hp are more prone to suffer passages clogs than carbs that have separate fuel pumps as in bigger engines. What find strange is that the white powder like stuff by passed internal tank filter, carb filter and pump's check valves. No problem was found whatsoever with standard gasolines untill we switched to E8, so E is the direct cause to blame for.

Has anyone had similar problems ? Alwayrs run fresh fuel and consume mostly all at the end of our boating day and top with fresh fuel on next constant outing. Does anyone knows if a water separator fuel filter will get rid of the white stuff ? if so, will consider to place one to avoid future constant carb cleaning.

Happy Boating

Luis,

That looks a lot like a gunk that we see when E gas and water combine. Because the pump on that style of carb doesn't have a lot of turbulence or velocity in it, the stuff can accumulate there, instead of passing into the carb bowl. If the stuff is due to dissolved water (instead of free water), a water-separating filter will capture some, but not all of it. OTOH, a water separator is never a bad idea. E is an aggressive solvent, which dissolves water and other things in the storage and delivery systems. Odds are that once the fuel stations, your tanks, and your motors have flushed all the dissolved stuff out, your problems will get somewhat better. Meanwhile, expect to clean that stuff periodically. Welcome to E gas