I believe, due to the lack of chainbrake and rear handle style, that you have either a 2500, 2600 or 2700.
Mike
Yes, I missed the different rear handle.
Also, if that's the original 33SL chain, it is hopeless unless you remove the shark fin bumpers - get a loop of 20BPX
Here is something I wrote up on these saws at one time:
<blockquote>Poulan 2500
Models include the 2500, 2550, 2600, 2700, 2750, 2775, 3050, PP255, PP295, PP4620, PP310, PP315, as well as the Jonsered 2036 and 2040. Displacements run from 36cc to 49cc. There is no primer bulb, and the Jonsered versions have a different shaped recoil and top cover just for decoration. The engines in this family are different from those in the Wild Thing family saws. For one, the crank is about 1/2” narrower, and the flywheel has shallower fins, allowing the whole saw to be lighter and much narrower as well. They are about 10lbs.
The connecting rod has an I-beam cross section. They use a chromed bore. The exhaust port shape is very similar to the Wild Thing, but the intake is a bit different. These saws respond very well to opening up the muffler and make a surprising amount of power for their displacement. They use Walbro WT carbs and a flocked air filter.
There is an external handle frame with a spring-type suspension for isolation, which tends to be rather soft.
Some of these are labeled “Turbo” and some are “Super Clean” - the Turbo versions use the small scoop by the flywheel fan to keep debris out of the airbox, while the Super Clean ones just have a pickup in the air stream between the cylinder and the carb. Only the Super Clean type parts are available any more, but they mostly interchange – there are some differences between early and later saws regarding the intake boot and impulse line.
Chain brakes are on most later saws. Most of these use 0.325” chain.
I have found three design weaknesses on these saws. First, the muffler heat shield on earlier Type I saws fatigue fails in the area around the muffler outlet. If you have a chain brake it can melt when the deflector falls off, and heat damage around the muffler is common. Second, the engine mount screws often back out. There is no locking hardware and they sit in a floating shoulder bushing that can spin so it would not work well anyway. Locktite will not work well with the thread type on the original screws. Many saws have been damaged by lost or broken screws. Last, the A/V mounts are easily damaged if the saw gets pinched and a gorilla tries to yank it out. </blockquote>