Chainsaw and 2 stroke maintence

[JOEPRO]

Since this is a chainsaw thread, I bought this saw a few weeks back as good used from ebay:



It's the most powerful chainsaw I have ever used and very easy to start etc. Seller sent it with spare new chains and the one on it was razor sharp anyway. Really pleased with it.

I also bought an Oregon electric chainsaw sharpener from screwfix will try it out soon. And a depth gauge of correct size to enable proper chain maintenance.

 

[DAPPH]

Nice buy , it's very very unusual to buy a decent second hand chainsaw from auction sites most have barrel & piston score or excessive wear ...... that's why they were sold to unsuspecting buyers .

 

[JOEPRO]

Nice buy , it's very very unusual to buy a decent second hand chainsaw from auction sites most have barrel & piston score or excessive wear ...... that's why they were sold to unsuspecting buyers .

It was an auction which I won at £340

This was the add:

STIHL MS391 CHAINSAW


I bought this chainsaw new from a Stihl main dealer a fewyears ago and it has only ever been used for cutting firewood for my own fire soit has not had a great deal of use. It has years of use left in it.

It has been very well cared for and only ever been used bymyself. After every use it was dismantled, thoroughly cleaned, tanks drained,carb run dry and the chain sharpened. Nothing but genuine Stihl chain oil hasbeen used.

It has a genuine Stihl chain and bar fitted, and alsoincludes 2 brand new chains (not Stihl). The original owners manual is alsoincluded.

I assembled it today after a period of storage, oiled andgassed it and it started up straight away and ran perfectly. (See video)

See it running here

Came with original tools and handbook etc, and very clean saw seller had it spotless. It runs amazing, very noticable torque to the engine. Made in Germany saw, for me worth the £ even for occasional use and if I don't use it I can sell it on after I get a number of mature trees dropped at the rear of my house.

I did buy the genuine chain oil etc as it has always been run on that and I don't use much anyway.

 

[Migmac]

Nice buy , it's very very unusual to buy a decent second hand chainsaw from auction sites most have barrel & piston score or excessive wear ...... that's why they were sold to unsuspecting buyers .

Even the knackered ones go for stupid money. Makes the majority of them not worth it for me,

 

[8ob]

Since this is a chainsaw thread, I bought this saw a few weeks back as good used from ebay:

View attachment 443217View attachment 443218View attachment 443219View attachment 443220

It's the most powerful chainsaw I have ever used and very easy to start etc. Seller sent it with spare new chains and the one on it was razor sharp anyway. Really pleased with it.

I also bought an Oregon electric chainsaw sharpener from screwfix will try it out soon. And a depth gauge of correct size to enable proper chain maintenance.

They are a really nice saw, only thing to watch on those is the bearing in the clutch/sprocket hub. For some reason they tend to knob/wear the end of the crank. Got three of them in bits waiting for me to come up with a lightbulb moment on an easy fix.

Bob

 

[Kram]

@8ob looks like they could be turned down for a hardened shrink fit sleeve? Crank is a £200 part otherwise

 

[paradipiro]

Checked the primer and it has a one way valve. The short/upper carb connection being the inlet and the long leg is outlet return to tank. The lower carb connection is inlet from tank - so it is supposed to suck fuel through the carb.

A bit more complicated than I imagined! A bit more to it than a motorcycle carb float bowl! All looked quite clean inside as I expected - its had little use and generally drain it if its not being used often.

The bottom peice seems to have a chamber and next filter to diaphram that seems to activate the valve? Im not sure what this does..

View attachment 443195

View attachment 443196

Any ideas, please?
I suspect as the primer is sucking through the carb, perhaps there is an air leak into the carb that prevents any suction reaching the tank, and also pressurising the tank..

On these "membrane" carbs, one side does the pumping action with the motors1s vacuum moving a membrane. (pulsing vacuum on one side, the other is fuel with one way valve) the other side is the membrane what replaces the floating bowl: the regulated pressure through a needle valve comes in: the needle is operated by the membrane, whitch is actuated by atmospheric pressure.
Simple as it is: through the fuel holes (low & high) the fuel disappears from the chamber, the membrane gets sucked in: opens the needle valve -> the fuel pump side pumps up the chamber-> needle closes.

 

[Kram]

Checked the primer and it has a one way valve. The short/upper carb connection being the inlet and the long leg is outlet return to tank. The lower carb connection is inlet from tank - so it is supposed to suck fuel through the carb.

A bit more complicated than I imagined! A bit more to it than a motorcycle carb float bowl! All looked quite clean inside as I expected - its had little use and generally drain it if its not being used often.

The bottom peice seems to have a chamber and next filter to diaphram that seems to activate the valve? Im not sure what this does..

View attachment 443195

View attachment 443196

Any ideas, please?
I suspect as the primer is sucking through the carb, perhaps there is an air leak into the carb that prevents any suction reaching the tank, and also pressurising the tank..

My Cs380 is still in bits It would be really useful to get fixed for abuse jobs like hedge trimming and stumps.

Using the 020T yesterday, at one point in the tree it wasnt starting and I could see the pull cord was worn. I got a couple more starts out of it before it let go.

Before I buy cheap cord off amazon I wanted to ask if any is particually good or long lasting? Whats recommended?
Perhaps kevlar or dyneema braid are more abraison resistant?

Also got to use the g372xp in a tree yesterday, it has loads of power! Great saw. I found when its under half tank it prefers running on its side. I guess because the tank is huge and where the pickup hose must be, I'll see if I can move it.

 

[DAPPH]

I always used Sthil or Oregon original cords off the bulk reels , make sure you put the right knot in the cord or they tend come undone at the most inconvenient moments

 

[Kram]

Starter cord done. Theres only one starter pawl, is this nornal? I dont think the other could have fallen out as its a single R clip, two would need a double R clip for both.

 

[JOEPRO]

Starter cord done. Theres only one starter pawl, is this nornal? I dont think the other could have fallen out as its a single R clip, two would need a double R clip for both.

View attachment 458771

Yes I'm no expert by any means but having taken apart about 20x Stihls the last year or so all of them only have 1no pawl so that's normal. My MS201T is very similar to that saw and it also has 1x pawl.

 

[Kram]

I am trying to find a .325 sprocket for the G372XP, it would allow me to use cheaper chains. I measure the sprocket shaft as 22mm diameter. They all appear to be 7 splines but variable diameter from 17mm, 19mm, 20mm, 25mm and 30mm. I cant find a single listing of a .325 in 22mm. 7 or 8 teeth shouldnt matter too much.

Ordered a bar and chain for £21 and a load of these for £2.70

https://www.amazon.co.uk/Trueshopping-Chainsaw-Standard-Chain-models/dp/B00FL8YZMU/

I may have to get a 30mm bore sprocket and sleeve it down to 22mm.

 

[Kram]

Also I got these last week, can never have too many combi spanners.

https://www.amazon.co.uk/dp/B0BXMZBFMF

 

[Kram]

I gave up looking. Theres probably a reason it does not exist, anyway I ordered this
www.amazon.co.uk/dp/B0CW2ZFV78

19mm bore, I need 22mm, lucky I have a lathe. Now I know 325" chain have 6mm deep driver links so 36.5mm OD -12mm drivers -22mm bore gives me 1.25mm each side for the splines, I suspect they are deeper!

Ofcourse being an 8 tooth on a 7 spline sprocket they are going to interfere.

So it may be that I buy a spare clutch drum, turn the splines off and braze the sprocket for this to work.

 

[roblane65]

I once converted my 550xp to run 3/8's chain ( full chisel ) on an 8 tooth sprocket and soon wished I hadn't . It turned it into a real grabby machine , the 8 tooth also caused issues with the correct chain length for the bar which was a pain so it went back to .325 on a 7 tooth
I still have the sprocket kicking around somewhere .

 

[Migmac]

I once converted my 550xp to run 3/8's chain ( full chisel ) on an 8 tooth sprocket and soon wished I hadn't . It turned it into a real grabby machine , the 8 tooth also caused issues with the correct chain length for the bar which was a pain so it went back to .325 on a 7 tooth
I still have the sprocket kicking around somewhere .

I use both chain sizes, prefer the 325 though. Feels like it cuts quicker

 

[Kram]

Using the G372XP and the fuel tank problem remains, which leaks a small amount into the air box. You can smell the excess fuel and becomes a real pain to start and keep running until the air box has cleared. Particually annoying when in the tree. When running it cuts perfectly, great power.

If I keep it running rather than stop between cuts, its less of an issue. The pickup seems to be in a bad place so gets starved when used on one side. Need to poke my fingers in there and move it.

I'll probably swap the new tank instead.

So instead my buddie passed up his 500i. Similar power, same bar length, fels much heavier and bloody aweful trying to start it. Its a fancy one with electronics and no choke but bloody hell does it hurt the wrists trying to start it, and thats using the decompression valve. I dont have the strength to pull the cord without doing a drop start!

 

[Kram]

I am thinking I should buy this to take it from 70.7cc to 76.8cc and gain a spare cylinder

Husqvarna 362 365 371 372 372xp 52MM Big Bore Cylinder Piston WT Ring Pin Circlip OEM# 503 93 93 72 from China manufacturer - Farmertec

Husqvarna 362 365 371 372 372xp 52MM Big Bore Cylinder Piston WT Ring Pin Circlip OEM# 503 93 93 72 offered by China manufacturer Farmertec. Buy Husqvarna 362 365 371 372 372xp 52MM Big Bore Cylinder Piston WT Ring Pin Circlip OEM# 503 93 93 72 directly with low price and high quality.

www.farmertec.com

Good idea? I assume the carb might need adjustment but wont need replacing?

 

[Kram]

Help needed please This has taken ages today mostly working out how to properly do the throttle cable.
I swapped the petrol tank and no leaks into airbox in any position.
Its back together, wont idle. It will fire on choke as is normal, turn choke off and it will start and run on fast idle. Any touch of throttle will bog and stall unless its full throttle that will run.

 

[dan.taylor.1]

Help needed please This has taken ages today mostly working out how to properly do the throttle cable.
I swapped the petrol tank and no leaks into airbox in any position.
Its back together, wont idle. It will fire on choke as is normal, turn choke off and it will start and run on fast idle. Any touch of throttle will bog and stall unless its full throttle that will run.

If you crack the fuel cap does it hiss or suck like it's pressurised?

Could have sucked some muck up in the swap and blocked a bit of the carb.

Running on fast idle but not at idle is definitely fuel starvation, maybe try turn the L screw out half a turn and see what happens