Thank you for showing this to us. Never in a thousand years would i have thought to fashion a spring as a hose clamp. Bravo.

Another symptom of an air leak and before doing a pressure test is turn it on its sides and upside down while running. The RPMs will noticably change or stall quickly. Just a tip. Thanks for the video brother 👍

I’ve a Stihl MS-170 for 8 or 10 years now and never had a problem with it. I use it a few times a year, so not much. As with all my two cycle engine stuff, when I’m done with it I always pour the gas back into my mixed fuel container then start and run it until it dies. Trying to get all the fuel out of the carburetor. So I’ve never had carburetor issues or had to replace the fuel lines. Very good video, thanks for sharing it.

I have one like that i use for a climbing saw. Great saw and power for it's size. It had the same issue as that. Got the new OEM fuel line and fixed the issue but i went ahead and pressure tested it anyway

Great fix. My father in law has this chainsaw so I’m glade to see you working on it, now I can reference both videos in the future if a problem comes up. Thank you

Pull the muffler and check piston and cylinder for scoring, sometimes you will still get a good compression reading but engine will run eratic.

I have a 170 with pretty much the exact same problem. Bought an aftermarket carb kit exactly as you described. The aftermarket fuel filter is on now and I'm still having the same issues. The new carb did nothing, same issues. I'm going to check the duckbill and the fittings on the filter now. This saw has driven me mental, I hope this could be the problem.

Oh dear what a problem that was. Not sure I would have been able to figure that out. Air leaks can be difficult to find. Thanks for the video.

I've had the same problem with the carburetor, apparently it's a problem with the 170... The filter and the fuel hose are always so easy to slide onto the carburettor, there is actually no need for an extra clamp around it. Kind regards from Germany

That would have frustrated the hell out of me ! Great job as always!

good job thats why u always buy oem stihl parts for stihl machines and not aftermarket junk

You can always adjust the metering lever for more fuel to run just be careful not to open it up as much because then it will flood and spit fuel through the muffler. Just adjust it very slightly and you will see major results

I would replace the fuel line, for it looked like it was soft and will restrict the fuel flow. I had that happen on a echo blower.

I saw another video on why a sthil saw wouldn’t stay running, they said the diaphragm was too far gone, also he drilled out an orifice near the needle and seat. Maybe this would prove helpful in future video. Have a great weekend!

I have the same saw with the same problem. I suspect the fuel line. Sometimes it runs very good, but an almost full tank will run badly. You need to burn 1/2 tank cutting wood to be sure of your fix.

Sounds like a leak in the fuel line that wasn't installed properly or has a hole in it from using a sharp instrument installing it. The gromet must be a good seal. That after market fuel line is defective.

Good troubleshooting!

Good day Never knew about the duct bill? Interesting Thanks good video.

Good job my friend good job👍👍👍

That still sounds like it’s running really lean. I would rather have a cheap Poulan that I can adjust the carb.

Thank you for the video

I'll give you 10 out of 10 for determination, sometimes, it feels like you're chasing your tail with fuel pipes but up to now, for me it's always been a carb issue 😊

The 170 takes a 0000 350 3500 fuel filter, the replacement was a 0000 350 3502 has the smaller end piece You can swap the end pieces over so you have a new filter in side. That old filter could still be some of your problem This saw still sounds lean, the carbs have fixed main jets so if you have a air leak the main jet won't supply enough fuel. Possibly the replacement carb has a larger jet so making a leak seem not so bad I always check for air leaks especially when the saw is old like this one. These models leak around crankcase sealant & main seals over time

Hey, I'm only getting audio from the left channel from the audio playing from the source.

oooh i build one of these fresh outta the box few days ago for my neighbor!! Cool thing (edit. neighbors was a MS180)

You probably should check the intake from air filter to the carburetor to make sure it isn't cracked

I would check everything !

Personally, I used kits like that one, and the spark plugs they include are junk. I was having all kinds of problems and I was thinking the carburetor was the problem, it wasn't, the spark plug was junk. I put in a Champion plug and it was running very rich, readjusted the carburetor and it ran great after that. Trying to tune a non adjustable carburetor can be tough.

The Air to fuel ratio is a important thing to have right every time

Are the new stihls that are coming out not have any adjustment screws.

Good afternoon, I'm fixing a customer's Husqvarna GT 2254, customer replaced drive belt, it looks right, I got the engine running by adjusting valve lash, when I went to drive test reverse is first, 1st is reverse. What would cause this, turning out to be a head scratcher, any help would be appreciated. Thank you, I learn alot from your videos, like you I also have a full time job. I do this on the side, also I find, fix and flip equipment. It's a manual transmission. Customer said it wasn't like that before, I never took drive belt off. 😂

well for me i,d try the basics including inspection on all the hardware in the carburetor aka carby and see if that,s in good shape and give it a good clean in the process and if that,s in good shape then move on to the fuel lines and fuel filter and replace if needed and if that,s all passing the delivery tests that,s good and if not replace them with the proper parts and then if i am still having the issues well i,d pressure test it as it can be often helpful and in other cases replacing the spark plug with a NGK or a Champion type instead of those Cheap Chinese made plugs which is what i reckon is in this video etc.

This is a fast and dirty test I was shown at the saw shop I work part time at for intake leak testing. Engine running, spray carb cleaner into the cooling air inlet at the recoil. Give it a short shot. If seal is leaking this spray will be pulled in past the seal and flood the engine right now. Sometimes we leave the top cover off and try to spray between engine and FW carefully. Engine still running and with the clutch cover off and spray around clutch. You can also spray around the carb to engine but you need to make sure you do not spray where the fresh air intake is for the filter, it will stall, flooded. I'll try to check the part number for an MS170 and see if it uses the large or small fitting fuel filter and the part number later this afternoon. Gary

New to the channel but we need a update on this does it cut good now?

I'm not sure if I would have caught that. Is that an mtronic model?

If memory my memory is correct, I think a wt215 carb will fit this. It has adjustment screws. Thanks for another great video.

Home garage I was going to ask you would you pick up a riding lawnmower if somebody just gave it to you! Also, I have one of those chainsaws, and I seem to like that chainsaw right there that you were working on

Awesome troubleshooting 🙏👍🙏👍

I believe you can actually tune those carbs you have to have a special set of drivers for them that’s why I hate newer two strokes

I was thinking there was a restriction in the fuel system somewhere since it always leaned out eventually and it'd be interesting NOW if the bar and chain was on so you could REALLY see what it did under load or lean out again, but that question has already been answered by the absence thereof. The electric start mower is running but not even close to right. The electric start is working perfectly with new battery and charger and will spin the motor over just fine. The motor has plenty of compression and when it starts, does so easily BUT when it starts will NOT restart. The only thing I haven't done is pull the new carb apart. No fuel leaks but the new primer doesn't work either but the thing acts like it's loaded up. It'll start with a dry plug with a whiff of ether and run but not exactly right as there is some whiffling with the operation. Tank has been off and is clean, no water, magneto has been wire brushed and oiled as well as flywheel magnets. Blade sharpened and balanced. I am REALLY thinking of pulling the throttle disc out of the OEM carb, replacing the broken stem with the one from the new carb and replacing the throttle disc and trying it out with the OEM carb since the only thing wrong after I cleaned the OEM carb up (main jet) is the broken throttle shaft hookup. The mower used to run fine but that was years ago and it will run good enough to get by now but just won't start back. Always something and BLESSINGS to U!

My screw keeps baking out how to fix& and

im new so if you havent made a video on polesaw can you do one

stinginess for the win!!!!😁

I think the new fuel filter was the culprit?

Or a implus lime

Oil seals

New OEM fuel line still should be installed.

Well she runs I would've probably done what you did,those carbs are a dime a dozen,probably was the issue,but a carb with adjustments,maybe,runs better than most good job...

It is running lean

Its still sucking air. Put a bar and chain on and make a cut. In the end that's the real test.

I wouldn't trust that fuel line long term and would have replaced it with an OEM.

Change the plug

Zama carbs aren't my favorite.

incorrect carb air ratio

Me without watching the entire video im.going to asume the new fuel line was made of cheap.material and was collapsing on its self.

What % of chainsaws and weedeaters come to you with a fuel related issues. Thank you, i could ask 100 questions but i wont do that to you.

A saw that doesn’t allow you to adjust the carb is a deal breaker for me. Very anti consumer.

First fit a good quality spark plug like an NGK or BOSCH & throw that junk Chinese plug in the bin.

A poulan pro is twice better saw than theses 😢