Ms290 burnt up!

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Mud man

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I have a ms290 it stopped running so I took it to the shop they said the motor was burnt up. They wanted 375$ to repaire. But I can get a complete engine for 100$ on eBay ... I'm new on the site plus I'm not a mechanic either. But I think I can repair it. Are there any particular parts that need to be torqued?? I don't want to trash a new engine....
 
I did not mix the gas properly. I poured the oil in the gas jug and did not shake it.
 
It's the line that goes from the base of the jug to the carburetor, just a molded piece of rubber.

The crankcase pressure creates a vacuum which allows the carburetor to pump fuel no matter what direction it's angled in.

If you are going to put a new cylinder on that saw it is highly advisable to replace all soft parts. Cheap insurance.
 
I'll be back in Ohio next week I may just bring the saw and let you take a look at it.
 
If I rella the piston and honed out the cylinder, what mm will it be. Ms290 is a 46 mm from factory. If I put the long block in that's a 49mm I could run a 24" bar. As of now I can only run a 20" bar
 
I had a 1 gallon wine jug I saved to use for something nothing really in mind just thought I should save it. Well I needed some mix the other day and my saw gas is a 1/4 mile out in the woods so I said well I will just mix up a gallon in this glass jug. I put the oil in the jug first then 1 gallon of regular gas. I was amazed how poorly it blended with the gas.
I bet I shook that jug,.." violently I might add" at least 50 times and there was still some un-mixed oil on the bottom of the jug. This is the stihl orange 2.6 oz ? bottle. You may have never ever have had an issue with you gas/oil mixture but I bet you don't shake it 50 good shakes ...do you ? If you could see what I saw it would give you a real education it did me.
 
that is why when you mix gas, you should only add a small portion of the fuel to the oil. Shake well and then add the rest of the fuel. (most mix oil bottles have these instructions right on the label) If the container is "full" it does make it difficult to get it mixed up properly. But hey, who reads instructions anyway. lol.
 
that is why when you mix gas, you should only add a small portion of the fuel to the oil. Shake well and then add the rest of the fuel. (most mix oil bottles have these instructions right on the label) If the container is "full" it does make it difficult to get it mixed up properly. But hey, who reads instructions anyway. lol.
That's a good idea. I'm going to try this from now on.

I normally only mix a gallon at a time in a 1 gallon can. The can will hold 1.2 or 1.3 so there is a lot of room to shake it around, but you can't see in to see when it's mixed. I'm going to try your method for sure.
 
If I rella the piston and honed out the cylinder, what mm will it be. Ms290 is a 46 mm from factory. If I put the long block in that's a 49mm I could run a 24" bar. As of now I can only run a 20" bar

cylinders are not honed. they have a nicosil coating. if you do repair this saw it's best to install the larger bore cylinder and piston. the 290 is 56cc and the larger bored 390 is 64cc, significant. except for the size of the hole and a decomp valve the saws are the same.
 
I was using 2 cyl oil from tractor supply. Honestly is it better to rebuild it vs. replace with a long block?
 
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