Running your carb Dry - Not sure it is a good idea

[smallribber]

My Yamaha 15 hp 2 stroke and Tohatsu 9.8 hp 2 stroke have always given next to no problems and I have done very little to them.

Recently I decided (as some do) to run the carbs dry after use because of the so celled fuel situation. I then started to have issues with blocked jets on both engines. I have never had this before and I never used to run the carbs dry.

I took the little carb off the 9.8 today and inside were some hardish small bits that were blue in colour exactly the same colour of my Quicksilver 2 stroke oil.

When you run the carb dry you absolutely cant get it all out and what little petrol remains I think evaporates and leaves dried out oil. I sprayed carb cleaner through the jets and all is good now.

Another very relivent point is that carb cleaner expands rubber O rings and the float bowl would not go back on easily.

To shrink the O ring just boil it in water for 10 mins then leave in the oven at about 230 C for about 10 mins and then it should fit. Test it during the oven period as you can if not carefull shrink it too much.

I know others use Aspen but this would not suite me.

As I said this has never happened in the past using E10 and E5 so I am not runnign my engines dry again. Well certainly not the 2 Strokes

[smallribber]

In the pic below you can see how the carb cleaner made the O ring expand.

[smallribber]

In this pic if you look carefully you can see the little blue bits. They are quite solid

[Fenlander]

I tend to agree and I know it doesn't suit your multiple outboard/boat scenario but I'm pleased to have the Aspen in so I have no need to run dry or drain for the winter.

[smallribber]

Originally Posted by Fenlander

I tend to agree and I know it doesn't suit your multiple outboard/boat scenario but I'm pleased to have the Aspen in so I have no need to run dry or drain for the winter.

I can understand in your situation it can be good but rather expensive. Apart from several engines I will some times just decide to go out on a nice day in the winter so I dont 'Put the boats away' as such.

The thing is I never had issues with the normal (E5 and E10) Petrol until I ran the engines with the fuel line disconnected until they stopped. Why did I do this you might ask....,........ Cos of various threads on here and other sites

[Matt73]

When you disconnect the fuel line the engine will run untill it cannot overcome the vacuum in the system and will stop. Some fuel is always left in the carb bowl, you can clip a spare fuel connector onto the engine whilst its running down or open the drain screw on the bowl to get rid of the remaining.

Matt

[smallribber]

Originally Posted by Matt73

When you disconnect the fuel line the engine will run untill it cannot overcome the vacuum in the system and will stop. Some fuel is always left in the carb bowl, you can clip a spare fuel connector onto the engine whilst its running down or open the drain screw on the bowl to get rid of the remaining.

Matt

Mnnnnn I think I will just stick to not doing it as I did not ever seem to have problems leaving the carb full.

Remember this happend on 2 outboards. What advantage do you think running then dry which will never be dry brings. I think it just makes any issues worse

[Wave Rider]

I don't run outboard dry. I run new E5 after 1 month. I don't have a built in fuel tank.

[jeffstevens763@g]

I tend to agree in the old days maybe a must but I never run dry gardening stuff now days do have the Mercury 2 st but aspen in that so no probs for 5 years maybe more.

[smallribber]

Originally Posted by Wave Rider

I don't run outboard dry. I run new E5 after 1 month. I don't have a built in fuel tank.

Where we live Tesco still sells E5 so I use that all the time

[Wave Rider]

Originally Posted by Easedalenovice

Where we live Tesco still sells E5 so I use that all the time

I use momentum as well. After boating I fill car up.

[smallribber]

Originally Posted by Wave Rider

I use momentum as well. After boating I fill car up.

My Car is Diesel

[smallribber]

I left the petrol that I drained from the carb to evaporate for a couple of days and the picture below is what is left. It is to the best I can establish small pieces of dried out 2 stroke oil. Some are soft but some are hard and they would certainly block jets in this carb.

My conclusion is that if you run your engine with the fuel line disconnected until it stops in an attempt to run the carb dry and prevent carb problems you are actually bringing on that which you do not want to happen and causing issues.

This might be different with a 4 strokes and perhaps different with other 2 stroke oil but this oil was quicksilver premium and used my many.

[beamishken]

Originally Posted by Easedalenovice

I left the petrol that I drained from the carb to evaporate for a couple of days and the picture below is what is left. It is to the best I can establish small pieces of dried out 2 stroke oil. Some are soft but some are hard and they would certainly block jets in this carb.

My conclusion is that if you run your engine with the fuel line disconnected until it stops in an attempt to run the carb dry and prevent carb problems you are actually bringing on that which you do not want to happen and causing issues.

This might be different with a 4 strokes and perhaps different with other 2 stroke oil but this oil was quicksilver premium and used my many.

Surely even you can work out from what you posted here that a larger volume of fuel sat in the carbs is going to result in more dried up fuel & oil residue. I dont drain carbs myself but surely even you should be able to work out from your post that the wisom of less fuel in the carb to dry up & congeal is a sound practice. Draining via the drain bolt is the best option as that gets rid of the water that sits below the fuel.
Another post designed purely to cause an argument however fortunately this time no one bit until you showed the futility of what your saying with your last observation.

[User name]

Originally Posted by Easedalenovice

I left the petrol that I drained from the carb to evaporate for a couple of days and the picture below is what is left. It is to the best I can establish small pieces of dried out 2 stroke oil. Some are soft but some are hard and they would certainly block jets in this carb.

My conclusion is that if you run your engine with the fuel line disconnected until it stops in an attempt to run the carb dry and prevent carb problems you are actually bringing on that which you do not want to happen and causing issues.

This might be different with a 4 strokes and perhaps different with other 2 stroke oil but this oil was quicksilver premium and used my many.

I'd agree with leaving it fuelled, unless it's going into long-term storage. Even drained, the pickup won't reach the pool in the base of the bowl. I just make peace with the fact that I'll have to do a carb service every year or two regardless of whether fuel is drained or not. That's just the nature running 2-stroke.

[beamishken]

Originally Posted by User name

I'd agree with leaving it fuelled, unless it's going into long-term storage. Even drained, the pickup won't reach the pool in the base of the bowl. I just make peace with the fact that I'll have to do a carb service every year or two regardless of whether fuel is drained or not. That's just the nature running 2-stroke.

If your laying up for extended periods draining the carb via the drain plug is the way to go, that way you get rid of any accumulated water & debris in the float bowl. Its worth squeezing the primer bulb a few times to flush out the bowl. Pulling the hose & running dry is only good for reducing fuel spills in the car when you lay the engine down.

[User name]

Originally Posted by beamishken

If your laying up for extended periods draining the carb via the drain plug is the way to go, that way you get rid of any accumulated water & debris in the float bowl. Its worth squeezing the primer bulb a few times to flush out the bowl. Pulling the hose & running dry is only good for reducing fuel spills in the car when you lay the engine down.

Originally Posted by User name

...unless it's going into long-term storage.

That's what I meant by the above. I wouldn't bother to drain it unless I was storing it longer-term.
Draining the carb can also cause issues with corrosion forming inside the bowl, especially when left in colder/more humid environments.

[A1an]

It’s a funny old world, I drain all my carb’d engines and never have a problem.

[69cmw]

I’ve never drained any of my outboards, motorbikes or garden machinery and never yet had any issues, sometimes leaving them for 8 months plus 🤷🏼

[smallribber]

Originally Posted by beamishken

Surely even you can work out from what you posted here that a larger volume of fuel sat in the carbs is going to result in more dried up fuel & oil residue. I dont drain carbs myself but surely even you should be able to work out from your post that the wisom of less fuel in the carb to dry up & congeal is a sound practice. Draining via the drain bolt is the best option as that gets rid of the water that sits below the fuel.
Another post designed purely to cause an argument however fortunately this time no one bit until you showed the futility of what your saying with your last observation.

I posted this thread as always to help others. Several people have replied in a respectful manner. One person has not. You can lead a horse to water