Stihl 011av

[Bertie3]

Hi I recently acquired a Stihl 011av.

it was in poor condition and won’t start.

the saw has 150psi compression, good spark and gets plenty of fuel.

I’ve cleaned the carb and put a new gasket kit in it, in fact, I swapped out a carburettor from a different saw same model that did work and put that on it and it still does the same thing just floods.

ive also replaced the gaskets under the carburettor and reed valve.

The spark plug threads were stripped as well, so I fixed that and put gaskets on reinstallation.

if it does start it runs away then dies.

I understand I need to do a pressure and vacuum test however I don’t think you can get the oil seals anymore, well I can find one but not both.

I don’t own a pressure and vacuum tester.So the cost of all of this makes me think it’s not worth it unless anyone on here might know where I can find the seals I require or insight into the problem.

 

13 x 19 x 4 - 96400031320

13 x 21 x 4 - 96400031330 (can’t find)

 

any help / advice much appreciated.

 

kind regards 

 

 

[pleasant]

Dont start taking the barrel off without an idea what you are doing. Unlike 'normal' saws the piston and the crank bearings arent caged...they are small individual needle rollers which just fall out unless to have the stihl tool or are pretty inventive. Once fallen out they are a bastard to refit.....even if you can. Seen loads of repairers give up on the 009 010 011 and 012 models which are similar in design once theyve been taken apart that far 

[spudulike]

It sounds like he has had the cylinder off already but totally agree with Mr Pleasants synopsis of the big end construction. My method on my 009 included heavy grease and tweezers....not the easiest!!

[Bertie3]

Hey thanks for the response and yes cylinder was off but it’s all back together again was abit tricky but managed, didn’t want to risk any chips getting in there.

any thoughts on where to get the oil seals?

unless you have any bright what the problem might be.

 

[spudulike]

Flooding of the saw when it is standing for a time is generally the needle valve in the carb leaking. This can be caused by hardened diaphragms, worn needle, dirty seat, weak spring or incorrect needle arm height.

You can use a pressure gauge or pop off tester on the carb to check it or simply just a short length of fuel line and blow/suck on it to see if it seals. The latter isn't quite as stringent a test but has worked in the past before I got all the relevant kit.

[Macpherson]

  On 17/03/2025 at 13:35, Bertie3 said:

Hi I recently acquired a Stihl 011av.

it was in poor condition and won’t start.

the saw has 150psi compression, good spark and gets plenty of fuel.

I’ve cleaned the carb and put a new gasket kit in it, in fact, I swapped out a carburettor from a different saw same model that did work and put that on it and it still does the same thing just floods.

ive also replaced the gaskets under the carburettor and reed valve.

The spark plug threads were stripped as well, so I fixed that and put gaskets on reinstallation.

if it does start it runs away then dies.

I understand I need to do a pressure and vacuum test however I don’t think you can get the oil seals anymore, well I can find one but not both.

I don’t own a pressure and vacuum tester.So the cost of all of this makes me think it’s not worth it unless anyone on here might know where I can find the seals I require or insight into the problem.

 

13 x 19 x 4 - 96400031320

13 x 21 x 4 - 96400031330 (can’t find)

 

any help / advice much appreciated.

 

kind regards 

 

 

Expand  

 

Hi, I concur with all that's already been said but I'd like to add that I've used a 012 as my firewood saw for 30ish years and in the last few of these years I've been nursing it quite a bit due to similar issues to you.

 

I don't believe that there's much difference between the two saws except 4cc's and that your 011 may have contact breakers rather than electronic ignition.

 

about 30 years ago when I bought mine S/H I kind of went through the whole saw apart from splitting the crank which at the time had a little up and down play in the crank as this type of roller bearing has and would have even if replaced..as I've found in other engines... a few thou, but not excessive.

 

As already mentioned stripping the cases is a bit of a faff, but not terrible, although I'd probably want to replace the bearings of a 45 year old saw along with the seals... but on the other hand if it's done no work, you might get away with it.

 

Which seal is it that you can't find?

I'm potentially looking at the same job as you and there is the larger 21mm OD seal on ebay from China, I can only find the 19mm OD seal at 3.5mm wide rather than 4... I can't see why that wouldn't work .... Although******!!!??

 

If you have it wanting to start, which is like mine on cold days, as it is the winter... leave it somewhere warm for a couple of days which may soften hard old seals, take off the tiny air filter cover and squirt a teaspoon of mixture right on top of the reed, it'll be like it's flooded for a couple of pulls and then give you a few seconds of life... repeat several times and you may get life..

 

Bearing in mind that your carb may be well out of adjustment. so a starting point of 1 1/2 to 2 turns out on L & H may be a good starting point,

 

Anyway , once you get it to run and get it tuned, if like mine. your problems may evaporate and you'll just need to repeat the process after next winter..

IMO these are great wee un-burstable saws that pull well above their weight because of the reed valve, their noisy they and sing as they rev right out.. old school .. just like me.

 

good luck.

 

 

[Bertie3]

Hello thanks again for the replies.

yes it is the larger one (13x21x19) the smaller one seems to be still in stock in various places online.

so I did have another look on eBay and found this.

 

Oil Seal 5mm-15mm Rotary Shaft FKM Rubber Double Lip Stainless Steel Spring TTO

WWW.EBAY.CO.UK

---

Material: Fluorine rubber skeleton oil seal. 【Wide Application】- Oil seals are used to protect shafts and...

 

Only thing is it’s Max operating temperature is 260°C.

I’ll have another look at the carb I have cleaned and rebuild that.
I’ve swap carbs with a different saw (010av) that runs great and both carbs work on that but not the 011av which makes me believe the problems elsewhere.

Could a bad oil pump cause the issue, it is run off an impulse of the engine and when you test for pressure and vacuum, you have to blank that off.

thanks again for all the support.

 

[Bertie3]

Sorry my mistake oil seal 13 x 21 x 4.

regards

[Macpherson]

  On 18/03/2025 at 11:14, Bertie3 said:

Only thing is it’s Max operating temperature is 260°C.

Expand  

 

I could be wrong, but I recon they'll be fine, a quick search has a average saw running at 350F or 180C

These would be an option with a smooth outer surface rather than ribbed, and you've only got to buy 2.

 

TC Skeleton Oil Seal Ring Rotary Shaft Sealing FKM Double Lip Seals ID 11mm-19mm

WWW.EBAY.CO.UK

---

Type: TCSkeleton Oil Seal Rings. Due to factors such as lighting, angle, display ect, there may be slight differences between the photos and the actual product. Features:...

 

[spudulike]

A real bad air leak = no fuel mix entering the cylinder so the engine doesn't start.

A slight air leak = high idle speed, over revving at maximum revs.

What are the symptoms you have again...is this machine flooding when you are pulling it over with full choke many times or just when the machine is left sitting there?

On your first post, the saw doesn't start and then it runs but dies and also floods at sometime....a good diagnosis begins with accurate symptoms.