Wet carburetor gaskets

[kfd518]

Cheapo fuel filter or OEM? Have had them act the same way you describe with not wanting to move around the tank.
Haven’t had a carb as worn as described a bit ago that’s a hard used bigger there.

 

[Stump Shot]

Well, as fun as it sounds, I have never tried to alter a saw from stock in any way. Clearly I have my hands full just making a saw run correctly ....
I am leaving the manifold bolted to the cylinder and blocking at the back of the carburetor. It's a bit maddening to me that I cannot test the carb to manifold gasket, other than spraying with brake cleaner.

I really hope it's the fuel line getting stuck. Not that I have a good answer to what to fix that with, but at least I could identify the villain.

I have approximately 15 saws of all sizes, all of them were trash saws or cheap finds. Some only needed fuel lines, all the way to built from discarded parts boxes. None of them have fought me like this saw. It's my greatest foe.

Keep after it, before you know you will stop finding what's not and find what is the trouble.
You might have it with that fuel line, I wouldn't be surprised if it had a crack in it, or hung up in the tank somehow.
Sometimes it's such a simple thing we tend to pass over it at first.
Best of luck to you with your troubleshooting going forward.

 

[Reveller Saws]

Cheapo fuel filter or OEM? Have had them act the same way you describe with not wanting to move around the tank.
Haven’t had a carb as worn as described a bit ago that’s a hard used bigger there.

Of course I have an oem filter haha hahahaha. On an unrelated note I'll be headed into town tomorrow, you need anything?............

I honestly don't know where this filter came from, but tomorrow it's headed for the bottom of the ocean.

Keep after it, before you know you will stop finding what's not and find what is the trouble.
You might have it with that fuel line, I wouldn't be surprised if it had a crack in it, or hung up in the tank somehow.
Sometimes it's such a simple thing we tend to pass over it at first.
Best of luck to you with your troubleshooting going forward.

Thanks. I have been after this saw for 3 or 4 years, try something and set it aside. It's time now, my saws all have to earn their oil stain. I don't care if I have to replace parts 1 at a time until it's a 572....

I did pressure and vac test the line, but stranger things have happened.

 

[Shane¹]

Cheapo fuel filter or OEM? Have had them act the same way you describe with not wanting to move around the tank.
Haven’t had a carb as worn as described a bit ago that’s a hard used bigger there.

I have seen the worn out throttle there was a few choice words before I ever figured this one out

 

[kfd518]

Only reason I ask is some of the chincy aftermarket a don’t have enough weight to pull the fuel hose around.

 

[bertfixessome]

A partially blocked transfer port will cause excessive pressure in the impulse path.
There is a action called "reversion" where pressure pulses become harmonic and cause the fuel to flow backwards out of the carb, although this usually manifests itself as a petrol soaked air filter
Try both raising the idle speed and lowering the idle speed

 

[Maintenance Chief]

I'm kind of having the same problem with the 625/ 272 hybrid I just built.
Im suspicious of the tank vent? As its outlet is pto side and the vent is flywheel side.
I've replaced it and tried to fix the original one with a duckbill from a poulan, while in the process I found a bad wire spot.
Basically same symptoms as your saw, but I'll run fine for about 5-10 minutes before it starts.

 

[Reveller Saws]

I'm kind of having the same problem with the 625/ 272 hybrid I just built.
Im suspicious of the tank vent? As its outlet is pto side and the vent is flywheel side.
I've replaced it and tried to fix the original one with a duckbill from a poulan, while in the process I found a bad wire spot.
Basically same symptoms as your saw, but I'll run fine for about 5-10 minutes before it starts.

I ran a vacuum test on my tank, it holds no vacuum at all so I was able to rule that out. Also I have run the saw with the fuel cap cracked, no change

 

[Reveller Saws]

Well, this will stall a moment. Went to my local shop and they had no Husqvarna fuel filters in stock. Tried to offer me an unweighted Stihl filter.

So what are the requirements to be a dealer? I suppose if I had 3 new saws and a sign I could be a dealer? The idea of advertising repairs with no parts in stock seems pretty foolish. Rant rant rant. I'll post more after my online order shows up.

 

[Stump Shot]

Well, this will stall a moment. Went to my local shop and they had no Husqvarna fuel filters in stock. Tried to offer me an unweighted Stihl filter.

So what are the requirements to be a dealer? I suppose if I had 3 new saws and a sign I could be a dealer? The idea of advertising repairs with no parts in stock seems pretty foolish. Rant rant rant. I'll post more after my online order shows up.

New normal.

 

[Maintenance Chief]

Well, this will stall a moment. Went to my local shop and they had no Husqvarna fuel filters in stock. Tried to offer me an unweighted Stihl filter.

So what are the requirements to be a dealer? I suppose if I had 3 new saws and a sign I could be a dealer? The idea of advertising repairs with no parts in stock seems pretty foolish. Rant rant rant. I'll post more after my online order shows up.

Im not sure whats on all those shelves ? But 90% of the time its nothing that will work for my 25+ saws! Haha
Im pretty sure that's why online sales are beating the pants off most dealers.

 

[bertfixessome]

Two problems
Biggest one is a university qualification called an MBA.
Every manager has one , they all get taught from the same test book & they all think ( or don't think ) the same .
Thus stores are not allowed to keep any more stock than they sell on a monthly average so things run out .
Their management theory tells them that we the consumer are totally brand loyal so if we can not get "their
branded part we will go to another branded franchise outlet or just weight till the part is in stock.

Next one is outsourcing all production to 3rd world countries so low value parts often run out if there is the slightests supply chain disruption .

As for filters, there is no such thing as a Stihl or Husqvarna filter.
The filters are Walbro , TK, Zama products that Stihl have used in that model saw .
All filters for hand held tools are weighted.
In the case of a Walbro the "weight" is the cast zinc housing .
For Porex style it is the weight of the porclean element itself .
Same story for sintered metal filters although you don't see them in chain saws much now days .
The only filters than need an additional weight as such are the felt filters in a plastic body .

Because of the Triple Bottom Line theory of management ( MBA's again ) where ever possible all costs have to be eliminated and dumped onto some one else so you can show the highest return from the $$$ you have invested in the business .
This means the cost of holding inventory ends up at the warehouse .
Several years ( perhaps decades ) ago the repair shops would order parts on a job by job basis either for parts not held or sock replacement
submitted automatically by the shops softwear as no shop runs a purchasing manager any more ( MBA's again ) .
Thus the warehouse would get thousands of tiny orders every day
It costs a warehouse almost the same to pick a 100 item order as a 1 item order so to cut costs at the warehouse ( MBA's again ) most warehouses have a minimum free prick .
Down here dealers for most brands get 1 free pick a month after that a picking fee ( $ 75 in the case of MTD ) is added to the parts invoice
Stihl down here have a minimum order value of from $ 3,000 to $ 8,000 depending upon the actual franchise dealer

Now we come to the animal called on line stores
Firstly they get your money before you get the goods and in many time this cam be several months.
Next many of them have zero stock so you place an order with them and they send that order to the factory / warehouse that post the part directly to you ( drop shipping ) or add it to that days / weeks order to the supplier.
Because the volumes per item are higher they can afford to keep higher stock quantities and they only keep high sales volume items.
No one complains if Scamazon does not have parts for a 20 year old saw as we do with franchise dealers.
Staff, usually there are none, all done via a computer with perhaps a single person on a phone or the number is outsourced to a phone answering service . We used to rent spare pallet spaces to these pond scum who ordered containers from 3rd world countries then sell the same item under a dozen or more different names , We then put the required lable on the unbranded trash, & sent it off to the purchaser .
In the case of Scammon we know their staff work in virtual slave labour conditions and are forced to do a minimum number of picks / hour thus the picking cost for the warehouses are very very low
Our costs used to be $ 4.25 Amazons are 8¢

And then we have the idiot customer factor
I know there is no difference between the various filters , as did your parts salesman so he knew the filter he wanted to sell you would work fine but you the customer has been hood winked that only the propriority brand of filter will work in your saw ( MBA's again )
I used to keep 38 different fuel filters
Now I keep nothing but porex cylinder type filters and a 1/2 dozen wicking ( flat tape ) filters for the reason of inventory reduction and costs reduction as I can buy the filters in lots from 200 to 1000 direct from the factory for peanuts and as stocks run down, I will be further reducing the inventory from 5 sizes to 3

 

[kfd518]

In my experience and I don’t know if it’s internal tank geometry/filter size or what but husky branded filters in certain husky saws just work best. In other words some of the tiny non porex filters get stuck in the tank and do not move as they should. I’d not a brand loyalty thing it’s a what works in my experience thing.

I have rifles that don’t have more than 2 parts by the same manufacturer just because the parts I wanted weren’t made by any one particular manufacturer but I can tell you one thing they go bang and put a projectile where I want it every time, took the time to research what I wanted and waited to get it at a price that I was willing to pay.
Most people these days are not brand loyal at all!
Those mba’s better get it together, more and more people are wanting to keep their money local especially in communities such as that on this forum.

 

[bertfixessome]

porex filters come in different sizes and the same size filter comes with a couple of different sized outlets
So it is just a case of using the right sized filter for the application.
Obviously the OEM one is the right size & weight so yes there can be a bit of trial & error .
The only time you have to use the makers brand filters is the ones that go into the stupidly flat tanks that need the long wicking felt ribbon filters usually found on line trimmers .
As for MBA's
We get more of them every year and they end up in the top 10% of income earners which is why the MBA attracts so many greedy people who worship money
Because the bulk of investment capital is controlled by funds managers and funds managers usually have MBA's no chance of erradicating those pests until company laws are reformed and there is zero chance of that happening because those who have the gold make the rules .

 

[Reveller Saws]

All filters for hand held tools are weighted

Definitely a weight difference between the filter I was handed and the filters I have in my toolkit, so your sentiment about no differences is not accurate in my opinion. I am looking for a problem that did not go away with the two filters I have tried, so I'm willing to go for a more reliable fix before I rule it out.

I normally do agree with you on the "if it fits it's perfect" as far as filters. I have 18 saws and I have never gone looking for a specific brand of filter. This saw is just trying to murder me.

Thanks for your input though, I appreciate it, it's a crazy world of businessmen and brand loyal woodchucks out here!

 

[bertfixessome]

Interesting.
So another little gem to store in the back of the head if I get a 625 or 272 into the shop for repairs.
I do not do many chain saws .
Most of the customers run shop branded saws which I will not touch any more .
If they want to buy cheap junk then they can run themselves ragged trying to get parts for them .
I was a bit green when I bought the repair run a decade or so ago only ever working on the neighbours Echo & my Stihl so it was a steep learning curve to sort out the repairable from the time wasters so generally I use the line "My hourly rate for chainsaw work is $ 150 / hr and there will be at least 2 hours labour + parts " that causes 90% of them to work out my repair will be more than another supermarket / Scammazon / Evilpay cheapie & they go away .

In fact now I will not even sharpen the chains for off branded saws, they can go buy another 5 chains for $ 30 that are worn dangerous before the first tank of fuel has run through it .

 

[Reveller Saws]

So I have been able to make some progress, although there is a gap left for me to jump. It's coming back to the gasket between the carb and the block. If I get it idling and spray carb cleaner near the bottom of the block, I can make the saw shut off. I have definitely done this test and had no reaction before.

I am not sure I know why I can't make that seal work. I have tried a couple different gaskets, maybe my gasket material isn't quite right. No cracks in the block that I can see, everything seems normal.

Oddly, it's relieved that I know where the next issue is, even though I don't know the answer. Fuel filter finally arrived, but I'm pretty confident that's just for looks now.

 

[davidwyby]

Have you checked for flatness? I think I have had to sand some mating surfaces on 2 series intakes tracts.

 

[Reveller Saws]

Have you checked for flatness? I think I have had to sand some mating surfaces on 2 series intakes tracts.

So the intake block has ridges molded into the plastic, hard for me to check flat on that, you think I should flatten those?

 

[Reveller Saws]

I did it. Figured it couldn't make things any worse. Of course it didn't make things better either. Pulled the block, flattened both sides and the carb face, slammed it home and was able to repeat my carb cleaner diagnostic. At the very bottom of the carb I'm leaking air.

That's enough for tonight, I have officially lost faith in my own gasket skills. Tomorrow morning I'll 3d print some TPU gaskets as a control test and see if I have better luck tomorrow night.