My Poulan Pro chain saw (model # PP4620 AVHD) doesot move B&C oil from the oil reservoir to the chain. How can I repair this?

fill the oil reservoir to the top, each time you fill gas reservoir, a quart of oil usually should last you the use of a gallon of gas.

Run it at 25-1 fuel oil mix, always use a good quaility two stroke oil designed for chainsaw use.

If the ports where the oil comes out aren't clogged, you will have to order a oil pump and then take apart the saw from right underneath the bar. The oil pump is run by a worm gear that strips easily.

The filter can usually be caught with a hooked wire and drawn up far enough to deal with the filter. Oil filters are not prone to plugging unless the oil used is contaminated. If you run the engine without the bar and chain attached, oil should ooze out of the engine side port. If nothing, suspect problems with the oil pump. Some saws use a plastic gear in the pump and can strip the teeth of the gear. You should find it located behind the clutch assembly. Once you have oil flowing from the engine, clean the bar drive-end oil ports that go from the large holes out to the chain groove on each side. Finally, run the bar tip near some cardboard--it should throw off a thin line of oil. I have no idea what the plastic tube might be (a manual pumper perhaps?). Hope this helps!

the adjustment screw near the end of the bar( next to the engine) needs to be turned in to tighten the chain just don't tighten it to much

The easy fix is to drain the oil tank when not in use. Many saws will leak some oil initially, but should not continue to do so. If it is making a large puddle, oil is getting past the oil pump which may be worn from long use. Make sure the tank vent is not plugged as heat from the engine can increase pressure in the tank thus forcing oil out. Hope this helps!

That part number does not cross. If the original or equivelant 20" bar find it here (all 0.325 pitch with 78 drive links; AV, AVX or AVHD):
Oregon Bar & Chain Selector
http://www.oregonchain.com/pro/lookups/selguide.aspx?BusId=OCS&SellReg=USA&LangId=ENG

If you have more questions or need additional help please reply below and I will get back to you. Thank you for using FixYa and Good Luck. HTH
Lou

It is a Poulan PP4620(dependent on clutch adjuster - AV, AVHD, AVL or AVX)
Poulan.com/CurrentModels (Check in Illustrated Parts List (IPL) box)
http://www.poulanpro.com/node4043.aspx
Type just the model numbers (choose the suffix after the list is provided).

All 4 of these display an outboard clutch, use this as a removal guide:
R² Drive Link Outboard Clutch by Drivelink.blogspot.com
http://www.youtube.com/watch?v=cdqkIuVNUQc

1. Check the IPL for your saw to see if any special tools are needed. Poulan (Craftsman, Jonsered, Husky) clutch removal tool part number 530031112 if needed, is under $5 from many sources (look at the visible area between the weights if 2 small round sockets are visible you need the tool).
2. There are metal piston stops available, when square (almost never) with the piston top these work well, if not square they have been known to punch through the piston. I suggest a length of nylon rope (nothing left behind) be used instead of the piston stop (retain 6" ± so you can remove it). Make sure the piston is near the top of the cylinder before feeding the cord or it can fall through the exhaust port and damage the piston as it rises.
3. Everyone I have ever removed had a left handed thread (tighten it to loosen it).

If you have more questions or need additional help please reply below and I will get back to you. Thank you for using FixYa and Good Luck. HTH
Lou

If you entered the 42CC 18" it is a PP4218(AV, AVHD or AVL) Gas Saw Type 2. The letters after the 18 correspond to the type of chain tensioning system.
Poulan.com
http://www.ordertree.com/modelinfo/POULAN-WEED-EATER/75.59.html
The dash number of your serial number is the type. Match the "Handle, Chassis and Bar Assembly" with your saw to complete the IPL.
An OM and less detailed IPL for your saw can be found here:
CurrentModels
http://www.poulanpro.com/node4043.aspx
Type just the model numbers (choose the suffix after the list is provided).

If you have more questions or need additional help please reply below and I will get back to you. Thank you for using FixYa and Good Luck. HTH
Lou

There is an illustration on the link that should provide what you ask.
http://www.fixya.com/support/r3706813-2_cycle_fuel_system_repair

The IPL for your saw can be here:
The IPL (exploded parts list) for your saw is the only detail for fuel line routing and it is sketchy at best; components are listed but on multiple illustrations.
Poulan.com
http://www.ordertree.com/modelinfo/POULAN-WEED-EATER/75.59.html
The dash number of your serial number is the type.
Try PP4620 AV Gas Saw. HTH
Lou