2 stoke generator

[Just Primer]

Hello. It’s been a while. Love this sight more than any other. I have an old Harbor freight storm cat 800. I just now got it running again after a long time sitting. I had to install a new carburetor. Now it smokes a lot as it runs. Sometimes it clears a little, but it’s obviously not using the recommended 50 to 1 efficiently. Even throws out some oil out the muffler. I’m sure that a better spark would help, or it is just worn out and the rings are not sealing. However I just like to use because it’s easy to drag out and I can set it far from my tiny cabin and I barely hear it in the enclosure I built. Also 800 watts is normally more than enough to camp. Do you think it would be ok to try 40 to 1 and see if I can get it to smoke less? Or is there a hotter spark plug for a small motor? Thanks Steve

 

[micromind]

Running it hard for a while would help.

2 stroke gas engines are a lot like diesels, they don't like to run with low load, they like to work. It keeps them cleaner.

 

[ericm]

Hello. It’s been a while. Love this sight more than any other. I have an old Harbor freight storm cat 800. I just now got it running again after a long time sitting. I had to install a new carburetor. Now it smokes a lot as it runs. Sometimes it clears a little, but it’s obviously not using the recommended 50 to 1 efficiently. Even throws out some oil out the muffler. I’m sure that a better spark would help, or it is just worn out and the rings are not sealing. However I just like to use because it’s easy to drag out and I can set it far from my tiny cabin and I barely hear it in the enclosure I built. Also 800 watts is normally more than enough to camp. Do you think it would be ok to try 40 to 1 and see if I can get it to smoke less? Or is there a hotter spark plug for a small motor? Thanks Steve

Worn out rings won't make a two stroke smoke more. There's no oil in the bottom end to blow past the rings like in a four stroke.

The smoking is because the new carb is adjusted too rich. You need to adjust or rejet it. I have had new carbs that fit perfectly but needed quite a bit of tuning to make the engine run properly.

 

[PCustoms]

How are you mixing your fuel?

 

[The Cobbler]

it’s obviously not using the recommended 50 to 1 efficiently. Even throws out some oil out the muffler. I’m sure that a better spark would help, or it is just worn out and the rings are not sealing. However I just like to use because it’s easy to drag out and I can set it far from my tiny cabin and I barely hear it in the enclosure I built. Also 800 watts is normally more than enough to camp. Do you think it would be ok to try 40 to 1 and see if I can get it to smoke less?

40:1 is even richer mix, so it would smoke more .
rings won't cause 2 stroke to smoke more.
spitting oil out the exhaust is pointing to really rich mix.
are you sure you got the mix right?
have you given it a good run to get it good & hot?

 

[theoldwizard1]

The original spark plug (Torch?) is ****. Replace it with an NGK or other quality brand.

 

[larry_g]

After sitting for a time the fuel in the tank can spreate and the gas evaporate and leave oil in the tank. Did you flush and clean the fuel tank before adding fresh fuel and starting? If not, the new fuel can mix with the old oil and give you an oil rich mixture.

lg
no neat sig line

 

[Just Primer]

Yes I realized 40 to 1 was the wrong direction shortly after I posted. The spark plug was changed but just some kind of Ace hardware equivalent. I was thinking there must be a higher quality plug. It is flushed. That tank is very small and I have run it a few cycles. The carb may be the problem. It was just an eBay or Amazon replacement. I was amazed it fit and the thing finally started. But I still have to shoot carb cleaner into the carb to start it from a cold start.

 

[Just Primer]

I use 91 octane and mostly Stihl chainsaw bottles of two stoke oil

 

[Just Primer]

It may have old oil residue in the tank. That tank is not a very direct reservoir. I was thinking of just plumbing a bigger tank to the gas shut off valve anyway. It only runs about two hours or less on a load.

 

[mike93lx]

Small inverter generators are so cheap and quiet that I can't imagine messing around with an old 2 stroke. I bet there would be a payback on just gas and oil consumption, besides that longer run time

 

[American Locomotive]

Just put a load on it and see if it cleans up

 

[Chuckster in NJ]

Hello. It’s been a while. Love this sight more than any other. I have an old Harbor freight storm cat 800. Now it smokes a lot as it runs.

Generators are so cheap nowadays and I wouldn’t spend more than $20 on trying to fix it.
NOT a cheap genny but I suggest to get a Honda and you will thank me later!

BTW! That 2 cycle genny is old enough to smoke!

 

[Just Primer]

Messing around with it because I like to restore junk I quess. I have a 4000 watt Champion that I love. But it’s pretty heavy. I have a 12 volt separate wire to the tiny cabin that I recharge a lithium battery fan , movie player and lights. USB plugs and cig plugs. And I have 10 solar panels that I have yet to install.

 

[Just Primer]

My boys like to play video games on the large AC tv and I like to run the AC ceiling fan. And this small generator is the easiest quieter way to do that. But it’s not mandatory. It’s normally 74 this time of year and 50 in the morning or 47 and I have a wood stove. But my tiny cabin is super efficient. I have 6 inches of foam in the walls and 4 in the ceiling

 

[Just Primer]

I also insulated the floor and sealed it up tight with skirting. There are a lot of mice in the area

 

[Just Primer]

And my boys have a Nintendo switch which I also like because it’s 12 volt rechargeable and it can be stand alone

 

[Just Primer]

But one does like his Xbox

 

[AA/FC]

Generators are so cheap nowadays and I wouldn’t spend more than $20 on trying to fix it.
NOT a cheap genny but I suggest to get a Honda and you will thank me later!

BTW! That 2 cycle genny is old enough to smoke!

Hondas have never been cheap.... Especially these days. lolol.

 

[The Cobbler]

The carb may be the problem

I think it's probably running the engine too rich . are there any adjustments on it?

 

[Chuckster in NJ]

Hondas have never been cheap.... Especially these days. lolol.

VERY TRUE!^
I purchased a Honda 6500 genny ($2300) in 2010 and used it during Super Storm Sandy for 3 weeks and again for some long power outages and it served me well, however two years ago I installed a KOHLER 20k. whole house unit and decided to let it go this year and got $2800 for it……… The guy who bought it was very happy to get it and was impressed with how I keep all my vehicles and power equipment because the generator looked like new.

BTW! Proper maintenance along with synthetic oil and ethanol free gas is key for machines that sit idle for long times.

 

[ericm]

But I still have to shoot carb cleaner into the carb to start it from a cold start.

The carb is not tuned correctly. Carb cleaner will wash the oil off the cylinder walls, so it's not great for starting fluid.

 

[Just Primer]

That’s smart. I will use another primer. I’m not to interested in tuning a cheap carb . I think the varnish in the tank is the key. We will see. It was sitting for years. I poured out the gas. But the tank has a way if not letting it all out.

 

[chris142]

I have several of those generators. one saved us during a power outage as It kept my mothers breathing machine running .

First get a quality name brand plug. Stihl oil is junk FB rated oil! Throw it away. Echo makes a much better oil as does Lucas. Both are FD rated for less smoke.

Lucas is $10 @ orileys too. They only spin 3600 rpm so even 50-1 is a little too much oil. I recommend 64-1 in them to slow down the ******.

Thats 2oz of good quality oil per gallon of gas.

 

[ericm]

I’m not to interested in tuning a cheap carb .

Then it's probably going to run poorly.

Small equipment two stroke carbs don't come pre-tuned. If they work right for a particular application out of the box it's by dumb luck. You need to adjust them. For small equipment two stroke carbs there are usually low and high speed screws on the outside of the carb body. It's a minute job if you know what you're doing.

I think the varnish in the tank is the key. We will see. It was sitting for years. I poured out the gas. But the tank has a way if not letting it all out.

Old gas could make it run poorly. I assumed that you got rid of the old gas and replaced it with fresh premix.

Are you sure there's no air leaks in the intake system? That will make it hard to start and make it run lean, which can cause it to seize.

 

[Just Primer]

I’ve never found the adjustment screws on any carburetor affect anything other than the start up and idle. I’ve been hearing this idea for twenty years and I don’t understand where it comes from. It doesn’t change the jet size. Good info for sure tho. I will try a different oil. Draining this particular gas tank was like trying to get the rain water out of an old tire. So yes I did not purge all the old gas years ago. I may just install a larger new tank anyway.

 

[Just Primer]

I will adjust the air fuel if it cleans up the idle. But right now it idles great and the smoke comes and goes. It seems to clear up. I need to verify that I have a good quality plug. When I did test for spark before buying the carb it seemed weak to me.

 

[PCustoms]

I've never heard of a plug making an engine run rich

 

[Firebrick43]

I’ve never found the adjustment screws on any carburetor affect anything other than the start up and idle. I’ve been hearing this idea for twenty years and I don’t understand where it comes from. It doesn’t change the jet size. Good info for sure tho. I will try a different oil. Draining this particular gas tank was like trying to get the rain water out of an old tire. So yes I did not purge all the old gas years ago. I may just install a larger new tank anyway.

The idea came from engineers that design carburators.

High speed needles do affect high speed load. While it doesn't do as much as changing the main jet, it does affect how much fuel goes through it do to the taper of the screw and where it is in relation to the set/jet depending on model. I have no idea how you think that it doesn't affect high speed fuel. Every carburator I have ever adjusted with one has an effect if its not plugged

 

[Just Primer]

Ok thanks.

 

[dcg9381]

Then it's probably going to run poorly.

How do you tune a 2 stroke H side on a generator that is set for 3.6K RPM? I always tune my 2-stokes at WOT on the H side... Been doing that since model airplanes.

 

[jar944]

40:1 is even richer mix, so it would smoke more .
rings won't cause 2 stroke to smoke more.
spitting oil out the exhaust is pointing to really rich mix.
are you sure you got the mix right?
have you given it a good run to get it good & hot?

No, its more oil not more fuel. It's actually leaner.

Tune a carb to run 32:1, then run 50:1 you will foul plugs like it's a tic-toc craze.

 

[jar944]

I’ve never found the adjustment screws on any carburetor affect anything other than the start up and idle. I’ve been hearing this idea for twenty years and I don’t understand where it comes from. It doesn’t change the jet size.

You are confusing carburetor types. This isn't a keihn or mikuni pwk. The screws adjust the entire range.

 

[The Cobbler]

No, its more oil not more fuel. It's actually leaner.

ok, richer on the oil then. will smoke more

 

[ericm]

I’ve never found the adjustment screws on any carburetor affect anything other than the start up and idle. I’ve been hearing this idea for twenty years and I don’t understand where it comes from.

Because it's actually true in many cases on two stroke small equipment carbs. Some only have a throttle stop and a low speed mixture adjustment. Many also have a high speed adjustment. There are also some jets but unless you make radical changes the screws are plenty.

I've tuned many saw carbs and the high speed adjustment makes a pretty profound difference. You can adjust it from slobbering and struggling to get 8k rpms to screaming at 14k rpms.

Motorcycle carbs only have screws for the throttle stop and idle mixture. For any other changes you need to adjust needle position or needles or main jets (or slide cutaway or pilot jet or ....) depending on what part of the operation you need to change. Small equipment is either idling or running full throttle so their carbs are less sophisticated.

I put a chinese carb on my old Stihl FS85 string trimmer and it's adjustment was all messed up. It would barely start and wouldn't rev. Once I figured out that the low and high speed screws were in the opposite place from the OE carb, it only took a short time to get it to start and idle perfectly and run well at full throttle.