my ryobi chainsaw does not use the recommended amount of oil. very little is coming out of the supply hole. could the pump be a problem, how do check the oil pump is working

blundell, January 2009

I live in far north Queensland Australia and have had no trouble with the oil pump on my 7 year old 4450C. It has done massive amounts of work cleaning up after cyclones but very little in between. Perished fuel lines is all I have replaced.
And I'm pretty sure this is because of the climate.
Oils made for bar and chain are sticky so the oil doesn't fling. And when it's cold and you haven't used the saw the worm drive sticks.
There are two solutions I can think of. 1. Use ordinary motor oil. The RCS-4450C is actually a Komatsu Zenoah GZ4500 (now Husqvarna) the Zenoah GZ4500 manual recommends SAE 10w-30 all year round or SAE 20 in winter and SAE 30-40 in summer. It makes no mention of oils made for bar and chain. Yes, it will probably fling more oil using motor oil.
2. Before storing the saw run some kerosene through the oiling system. Be sure to run it until oil is coming out before using it again.

Arthur, April 2016

This is obviously a few years down the line from the original posts, but wanted to add something that may help others and save you going too deep and possibly causing more damage. After normal checks of accessible oil ports, if you are still not getting oil to bar and chain, the chances are that the worm drive is stripped. HOWEVER, it will be the pump gear that has caused this by seizing up, specially if the saw has been stored for a while. For some reason the oil gets sticky and gums it up. So while you have the clutch etc off, spray in some WD40 or similar, and using a small screw driver ensure the little drive gear (that the worm mates to) turns freely. Not sure how this gets lubed so would suggest some grease prior to fitting new worm gear. As previously posted, the gear will cost more than stated on 'Shoulders of Shoreham' site but they are about £11.00 + P&P on ebay. You can test oil is being pumped by running engine prior to refitting chain and bar.
Hope this helps you avoid some very un-necessary strip downs!

John, April 2012

Thanks Folks for the valuable input..ive followed the suggestions and have managed to dismantle the machine. The worm drive certainly looks to be at fault although its not possible to test the oil pump without a working worm drive - have i missed something - so i will replace that first and see what happens...trouble is I am in France

ryobiboy, February 2012

Fixing depends on model. I had the same problem with a RCS4450c chainsaw. It took a little working out but you do not have to dismantle the whole saw. The whole job takes less than an hour

For many petrol models:
Remove the clutch/chain drive cover by removing the two nuts. Remove the chain and bar by sliding the bar towards the clutch to provide slack.
Remove the starter cord pull (4 torx screws on my model).
Lock or brace the nut on the centre of the starter clutch with an appropriate spanner or socket.
Undo the drive clutch; it is the centre of the clutch assembly with an arrow and 'UNDO' stamped on it. I managed this by grasping it firmly with vice grips but see other answer for other methods to undo it.
Once undone, remove it and the small roller bearing race.
You should now have access to a nylon worm drive which turns the oil pump. On my saw the nylon drive had stripped. It appears to be sacrificial as the oil pump drive itself is steel. If this nylon part is at all damaged, replace with new. These are available from http://www.ryobispares.co.uk/html/chainsaws.html
Part number 518458001 but do check against your model. be prepared to pay somewhat more than the price quoted on the spares list. The part is listed as about £3. I had to pay £21 for two including postage.

Rebuild in reverse order. The worm drive needs to be gently screwed in to engage with the oil pump. If you push it you will undo all your good work by knackering the thread.
Replace the roller bearings. Engage the tangs on the outer part of the clutch with the cut-outs on the worm drive.
Replace the washer then screw the centre of the drive clutch back on - left hand thread so anti-clockwise. It does not need to be massively tight as the rotation of the clutch acts to tighten it.
Replace the starter pull cord mechanism. Ensure any wires are correctly routed.

At this point it is worth starting the saw to ensure that the oil feed is indeed working. Within a few seconds of start-up, oil should feed out of the oiler hole. If not then you have a different problem (has it got oil in it?)

Replace bar and chain. Replace clutch cover and adjust chain tension. Again start the saw and ensure that a small amount of oil is being flung off the chain at the end of the bar.

Job done.

Nanook of the north, January 2011

there is a small worm drive in these chainsaws and 9 times out of ten its that rather than the pump.it has happened to me several times

daradec, January 2011

I have the same problem , no oil coming out at all. Initialy I tried cleaning the oil way etc , this made no improvment.I striped the machine, and removed the engine. I sugest cleaning the machine with engine degreaser first, when you have removed the covers. Cleanliness is essetial because the engine crankcase splits in two when you remove it from the chassis. For the sake of a few small screws to hold the case halves together , a lot of bother could of been saved here.To remove the engine you will have to take off the cetifugal clutch. Start by removing the circlip and remove the chain drive cog. On the clutch mechanism you will notice an arrow with the legend "off" stamped this is the direction to unscrew the assembly from the crankshaft. I jammed the finned flywheel and used a piece of wood as a drift /punch . with a few smart taps the clutch unscrewed. Remove the handel and dissconect the throtel cable. The on/off switch and primer bulb assembly will all slide up and out in one unit. Remove the four bolts from the underside chassis, and the silencer. The engine will tilt out of the chassis , its a fiddle and the crankcase will seperate. The oil pump is on the clutch side ,fixed on by two machine screws. The pump will come appart by removing the end cap and withdrawing the worm-drive. A spare pump can be orderd from http://www.shouldersofshoreham.co.uk/sos_17Bamp.mvc?P=pcn-4040
click on the part number you require. pumps are about £7 + £5 postage.
Note all screws are of the torx type and you will need a good quality driver to remove some of them. Thay have been treated with thread locking compound.
You will need some gasket sealing compound , to lightly coat the mating surfaces of the crankcase halve's. Clenliness is essential here.

I havent orderd from shoulders of shorham yet, I wonder if at this point it is worth spending £40 on a new bar £25 on a chain £7 on the pump . A new ryobi chaisaw 4040 from B&Q is £134.

Steve Ward, March 2009

Start the chainsaw up, rev it up for 5-10 seconds with the bar pointing at a piece of clean cut wood, card or paper, the chainsaw chain should throw a light mist of oil on to the surface and the chain should be covered with a light covering of oil but make sure you have stopped the engine before inspecting.
If this isnt happening, check the oil way is clear with a small twist drill and if it is then check the filter.

The other thing to do is to take the side cover off, remove the chain and bar, start the saw up and rev the engine, the oil should come out of the oiler hole freely a teaspoon full every 5-10 seconds.

Lastly - check the oiler hole in the bar and make sure that is clear of debris.

DO NOT CUT LOGS WITH THE OILER NOT WORKING - at best it will destroy your bar and chain, if the chain snaps it will really hurt!!

Hope this helps

Steve, February 2009