Cooked Crank

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Chashowlett

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This saw has bad crank bearings and the big end of the rod lost a needle bearing and lunched the piston. It looks like it never had oil, can anyone explain how this thing oils the crank? Look real close because I'll be damned if I can see how the crank gets oiled....
 

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I use fuel that is in a can and pre-mixed, this is a customer's saw and there was oil in the gas. I want to know how oil makes it to the crank. Unless I am missing something...there is no possible way for oil to get behind the rings.
 
IMG_0025.JPG I have nice saws; this is what I use. Look at the base gasket where the openings normally are for the intake charge . How does the intake charge get to the underside of the rings?
 
Like Sty57 diagram. If he didn't like it he could have piped it lol. Spark plugs are cheeper than engine parts. More oil
 
View attachment 585990 I have nice saws; this is what I use. Look at the base gasket where the openings normally are for the intake charge . How does the intake charge get to the underside of the rings?
The Fuel charge goes under the piston when the intake is open and into the crankcase first. Then gets pushed up through the transfers into the combustion chamber.
 
The Fuel charge goes under the piston when the intake is open and into the crankcase first. Then gets pushed up through the transfers into the combustion chamber.
Yeah they got the good fuel. 50.1. Mix. Last for years, if I'm going 50.1 I use amsoil Saber rated to lube at 100.1 mix. 50.1 is very oily in the Lil top handle saws tried 40.1 and Lil saws didn't like to clean out in a small cut.
 
Look at the base of the cylinder, see the gasket? Now where the cutout is for the transfer ports, it's solid= no opening! How the F... is oil going to get under the rings? Every cylinder I have ever seen has openings that the intake charge goes into the crankcase thus supplying oil to the crank. Now pay attention this time- please explain how oil gets to the crank in this motor. The diagram is great but does not apply to this motor because the intake is not connected with the crankcase.....
 
Look at the base of the cylinder, see the gasket? Now where the cutout is for the transfer ports, it's solid= no opening! How the F... is oil going to get under the rings? Every cylinder I have ever seen has openings that the intake charge goes into the crankcase thus supplying oil to the crank. Now pay attention this time- please explain how oil gets to the crank in this motor. The diagram is great but does not apply to this motor because the intake is not connected with the crankcase.....
What brand and model is the saw?
 
IMG_0026.JPG IMG_0027.JPG IMG_0028.JPG Sorry, Stihl , I can't find a model number but here's pictures of serial number and a part number of the cover that the air filter mounts. It's a old chop saw
 
Depending on the part number on the first picture starting with 4201 I think it`s a TS 350 or 360. The serial number of your picture is also "near the range" of TS 350, 360. That`s why I think it`s one of these models.
 
Look at the base of the cylinder, see the gasket? Now where the cutout is for the transfer ports, it's solid= no opening! How the F... is oil going to get under the rings? Every cylinder I have ever seen has openings that the intake charge goes into the crankcase thus supplying oil to the crank. Now pay attention this time- please explain how oil gets to the crank in this motor. The diagram is great but does not apply to this motor because the intake is not connected with the crankcase.....
You sir, need a better understanding of how a two-stroke functions
 
Look at the base of the cylinder, see the gasket? Now where the cutout is for the transfer ports, it's solid= no opening! How the F... is oil going to get under the rings? Every cylinder I have ever seen has openings that the intake charge goes into the crankcase thus supplying oil to the crank. Now pay attention this time- please explain how oil gets to the crank in this motor. The diagram is great but does not apply to this motor because the intake is not connected with the crankcase.....
The combustion chamber on this cylinder is side fed.
The gasket they used for an earlier bottom fed cylinder.
Absolutely nothing wrong with that as long as the gasket was doing its job.
 

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