Jonsered 625 52mm conversion

[Stephen 92]

I just rebuilt an jonsered 625 with a 52mm big bore cylinder. I kept the same carburetor just switched the lids and intake to match impulse. The saw cranks with just a couple pulls, idles and runs great until it warms up then it shuts off. It will crank up for a second if I choke it but shuts right back off until it cools down. I need some ideas on what it could be before I throw it in a dumpster

 

[jacob j.]

@Johnmn

 

[67L36Driver]

I’ll pick the obvious: Coil.

 

[Johnmn]

The 625/670 carbs have an external impulse so the port on the carb is not drilled there is just a detent there. In order to use that carb with a 272 cylinder as you did you must drill the impulse port in the carburetor or drill an external port in the cylinder.

 

[67L36Driver]

@Johnmn

User name don’t show up right. Spelling?