Hunter

When massaged seller he said saw runs fine.

I have offered to visit to see saw running but he said he is not free, the following day I messaged again and he said sold subjected to collection but advert still out so not sure what is going on.

18 hours ago, peatff said:

 

The purge is hidden behind the pull start handle 😉 

Does purge make it likely to be newish?, what year roughly was it added

3 hours ago, Stubby said:

Do you need it ?

No need really. I am occasional chainsaw user so no need but want it 😂😂

This came up for sale local to me. Guy said it has been in garage for sometime but has been running. He wants £175 for it.

from picture it seems has been neglected.

would you buy such thing. Not sure from picture if it is the oldest of the newest 353 so it could be 10-20 years old saw.

All sorted now. Used but genuine  carb arrived from eBay, as expected it needed new carb kit. Fitted and saw up and running.

just got carb toned.
again thank you all for your help. 

On 28/02/2022 at 12:13, bmp01 said:

Tested both check valve with silicon tube. Problem seems to be the idle check valve, I can blow and suck air easily in both direction with no resistant at all. 
I compare itwith my other working carb where I can only blow air in but when try to suck air I can hear valve click and close. 

I have ordered genuine second hand carb from eBay.

thank you all for your help. I have learned a lot from all of you.

2 hours ago, bmp01 said:

So you've got 2 fuel circuits in the carb, a low speed and a high speed.

Low speed circuit is fed via the bung in your blue circle and there is a little flap check valve on t'side. 

High speed circuit is fed via the small hole below the main jet / check valve assy.

If you have a piece of small dia hose, preferably soft silicone, you can hold one end over the entry hole and blow / suck to confirm the check valve operation. Adjustment screws need to be NOT bottomed out. Low speed circuit will flow a lot less than the high circuit.... 

 

Will check and report back. Thank you.

52 minutes ago, bmp01 said:

I'm confused by your experiment and statement that its not sucking fuel.

I see fuel and air bubbles in  the return line. So it must be sucking some fuel through the carb, no ?

I don't see any air bubbles in the line between carb and purge bulb, is that all fuel?

 

Edit: Looks like 100% fuel in the line between carb and purge bulb. I agree with Openspaceman, you have an air leak around the purge bulb, might just be a loose fitting hose on purge bulb, or a cracked leg on the purge bulb....

Picture is for the working carb. The other carb Seen in picture to the left.

26 minutes ago, adw said:

Do you have a vacuum gauge? connecting one to the pipe may well open the check valve, will ordering this part be a better option rather than some crappy Chinese knock off carb. however as has been said the saw should still start, if you get it running it may well open the check valve.

I don’t have vacuum gauge. 
I guess problem is with main check valve which cause purge bulb to suck air rather than fuel from tank.

am I right thinking that the main check valve located in carb main carb body (see photo ) and not on Primer side of carb as those part was replaced but problem exists.

I guess time to order new carb.

I even tried removing the metering needle completely just to see in fuel will be sucked.

5 minutes ago, adw said:

So the check valve in the center section of the carb is stuck ( the part with the outlet purge pipe connect ) this part seems to be available as a spare part.

 

Exactly this what I thought. part 40 and 35 in diagram and all things in between and above has been tested by replacing all of them from a working saw carb and the carb did not suck any fuel hence I conclude that problem in one on the a pathway in main carb body.

3 minutes ago, adw said:

Can you just humor us, depress the purge bulb, whilst depressed blank the shorter of the two connections off with you finger, now let the purge bulb out with finger still over the short connection, does the bulb readily come out, or does it stay compressed?

Done this already and it stayed depressed

3 minutes ago, openspaceman said:

Firstly that air is getting in somwhere around the purge bulb because there is no air in the line from the carb.

 

Secondly if it is not sucking fuel into the carb are you sure you have not blocked the small hole between the metering diaphragm and the return nipple/pipe on the carb? The gasket may be upside down and 180 degrees out. Have you checked Spud's suggestion of the gauze filter between the pump and the inlet needle valve?

Hi

problem seems with carb body itself. There must be blockage in Fuel  inlet pathway.

as stated,  I have exchanged all removable parts from another working carb and it did not suck any fuel.

Thank you for every body who tried to help me.

On 20/02/2022 at 20:00, spudulike said:

It would help if you stated why you fitted a new carb kit and purge bulb. If the saw was a non runner then ADW is probably correct.

It is possible you have installed the carb kit incorrectly or even fitted one with the purge holes missing. The purge should suck  on one side and blow on the other. Easy to test with a short length of pipe and a cup of fuel.

 

Thanks spud.

the saw was working fine but due to I’ll health it was left unused for two years, actually all my saws were left unused and I am just started to sort them out. When saw tried with new fuel it was working but smokes a lot. I did put new air filter, checked compression it was 150, pulled muffler and piston like  mirror. I already got unused carb it so I have tried it. I checked the kit order as per parts manual.

I did not change purge bulb but tank vent.

I will check purge with short pipe and fuel as suggested 

Thanks guys 

On 20/02/2022 at 19:54, peatff said:

It sounds like the one way valve in the primer is faulty, just try blanking the pipe off or replace it they are cheap enough. Carb sucking fuel from the tank would create a vacuum not pressurise it.

which pipe should be blanked off please.

36 minutes ago, adw said:

Just to clarify, there are two connections on the purge, the long one is the pressure side so back to tank, the short connection is suction so goes to the carb, purging will create an amount of pressure in the tank, I have never seen one blow fuel from the breather, you should be able to at least 3/4 fill the bulb, biggest issue with this generation of machines  135/140/435 is ignition unit failures.

Thanks, yes all fuel line in right order.

I think problem should be in carb sucking fuel from tank, which lead to high pressure on tank and fuel has to place to go except tank vent. I guess  I may have to take the carb out and see

I have checked fuel snd return line and they are in correct order connection wise.

When I did change fuel line I ask cleaned and put new kit in carb and pretty shore it was put on right order, done this few times before. Purge bulb got fuel in it but only small amount.

I see. Fuel line is new and no splits

Here is picture

I need some help please.

33 minutes ago, Stere said:

Got  stihl  dynamic  BEAVER EXTREME 😏 ones and they are good v brambles

 

 

DYNAMIC trousers - With Design A / Class 1 protection and improved sizing

WWW.STIHL.CO.UK

---

Work trousers with certified cut resistance to BS EN 381-5, Design A. Preformed, double reinforced knee areas. Trouser...

 

Thanks. Looking for more affordable option like the functional range for occasional use. I guess they are going to be better than the Oregon and they are roughly same price £75 or so.

It’s an old thread and one of the reasons I bought them. Tried mine for the first time today. they are very comfy and I forgot I wear chainsaw trousers however they are very delicate.

this after only four hours work and came across few strands of bramble.

very disappointed.

how does STIHL SFUNCTION UNIVERSAL trousers in durability with bramble etc.

2 minutes ago, se7enthdevil said:

it's a bit out of focus but i can still see that it's very similar to eucalyptus species that get used for shipping and crates so i stand by my earlier statement...

Thanks mate, really appreciate your help.