Anyone used a generic replacement carb on a Stihl?

My Stihl SH85 blower, wonder of German engineering that it is, has finally died a slow agonizing carb death. This thing has never been easy to start, but it’s just gotten worse and worse and now it won’t stay running.

I notice the interweb is full of generic Chinese replacement carbs for Stihl equipment. They look exactly like the OEM carb that costs 3X as much from my local Stihl dealer. Probably made in the same factory as the OEM.

Anyone ever tried one of these generic replacement Stihl carbs on a chainsaw, blower, etc?

Yes, I could rebuild but damn these little carbs are SOOOOOO fussy to take apart and get everything right. I HATE doing rebuilds on this small 2 stroke stuff and especially if a complete carb is $20 shipped to my door compared with $15 for the carb kit from Stihl.

Anyone gone this route on small Stihl power equipment?

Grouse

Not on a blower, but I put an aftermarket carb from ebay on my Stihl trimmer, and it has never started easier, or run better. Go for it.

HRG

not on a stihl,but I have used a couple on restored honda 70 series trail bikes and they have worked great so far.
Grouse,if you decide to rebuild the one you have and dont want to do it,send it to me and I will do it for you.

I’ve gone with cheap no brand carbs on a few small motors. One was on a stihl saw. I haven’t had a bad one yet. I would make sure the carb looks exactly like the one you are trying to replace before ordering. Those little carbs can be really frustrating to rebuild.

I have and had no problems with it on my FS45. Tried one on my Honda TRX90 and it was a nightmare. Ended up buying a new OE and got hosed on it. But now it works great.

China needs your money. Go for it.

TheFamousGrouse wrote:

My Stihl SH85 blower, wonder of German engineering that it is, has finally died a slow agonizing carb death. This thing has never been easy to start, but it’s just gotten worse and worse and now it won’t stay running.

Have you tried cleaning the spark arrestor to see if that helps? My dads blower was having a problem and the mechanic pulled the spark arrestor, burned it off with a propane torch, installed it and the machine ran great.

Something to try before buying a new carb. The arrestors get clogged up causing running issues.

I’d listen to Hemi.

Send it too Sheldon grouse, I’ve done a couple but the hardest thing is to get them clean, it can also be tricky putting the diaphram needle back in with a pair of small needle noses or tweezers. My first was on a chainsaw carb, got it done but it was a challenge.

Thanks for the tip Hemi. I have an FS45 trimmer, looked a couple of YouTube videos and it sounds exactly like the fix for issues I have with it.

Thanks for the feedback guys.

Spark arrestor is a good idea as a last check, but a plugged arrestor doesn’t seem to match my symptoms. My blower starts and runs all the way through the rev range, but if you let it return to anywhere near idle, it bogs down and dies. Then it will not restart for love or money until it has sat for over an hour. Pulling the sparker reveals that the plug is wet, indicating flooding.

I can rebuild the carb, but I hate doing this on these little engines unless absolutely necessary. I was all ready to buy a carb kit when I was on some small engine sites looking up the part numbers, that’s when I saw everyone seems to carry generic full-on replacement carbs for a few dollars more than the carb overhaul kit.

Made me wonder if I was behind the times and none of the cool kids even bother with overhauling small carbs anymore?

Also made me wonder if there was any difference between OEM and the generics? Like everything else, Stihl is just a bunch of Chinese-made parts screwed together, so I can’t see paying 3X the price for a box that says “Stihl” on it. My Stihl dealer is making enough money charging for repairs that should be covered under warranty.

Grouse

You have obviously checked/changed the air filter and changed the plug? Seems odd that it would only flood out on it’s own after it starts and runs up to full RPM. I assume there are no low speed carb adjustments on it?

I assume you have tried restarting with throttle at WOT?

Yes, have even tried to run it without the air filter just to see if somehow the new filter was the issue. No luck.

There is spark and the plug looks fine on the plug checker, but I agree that’s another thing to try as a last ditch before tearing off the carb.

It’s a fully adjustable carb so I’ve pulled out the needles to make sure there’s nothing on the tips and then reset the H and and L adjustments several times. It “runs” fine when I start it and it revs up fine, but the return to idle makes the machine die. No amount of messing with the carb after it dies will make it restart until it sits for an hour.

It will not restart after it dies. Not on WOT, not at idle, not anywhere in between, choke, no choke, etc. It seems to be badly flooded.

One of the things that’s got me thinking bad carb is that the L adjustment seems to have the machine running best when it’s almost completely shut. Like open 1/4 turn. Never in my life have I seen a 2 stroke that runs when set up like that, but that seems to be the spot where it spools up through the low range without bogging or stalling.

I’ve never had a small machine that required this much messing with and it’s never been a good runner. When I got the machine, the carb went bad the second time I used it and the machine would not run at all. Dealer of course blamed me but then had to do the walk of shame after he was unable to start the machine himself. That time the carb had some kind of crack internally and I had to wait 2 weeks for a new carb to be installed. But that time the machine was stone dead, this time it runs but only as stated.

I’ll have to tear into it after deer season and see if I can get this figured out. Thanks for the replies 311.

Grouse

Another quick thing to check is the plug gap. Should be .5mm. I have read about some plugs coming as wide as 1mm which might cause the issue your seeing at low/idle speeds.

Well I’ve seen strange things with plugs so I put in a fresh plug. NGK calls for an .030 gap so thats what I used.

No change. Same exact issue.

Thanks for all the ideas 311. Carb overhaul here I come.

Grouse

Stihl specs call for .020 in.

Tell us what the problem was if you find out grouse, sounds like maybe a diaphragm needle valve issue with letting too much fuel through.

Yes, I’ll post the fix as soon as the Stihl gets off the operating room table.

So far I’ve replaced the air filter, fuel filter, and the spark plug. No difference whatsoever, so I have to think the carb is the logical next thing to go.

Since the blower still runs, I have about one more time I need to use it and then it’s going in for surgery. Appreciate all the replies.

Grouse

Update. The Stihl went on the table today. Tore her down and got the carb off.

My suspicions about Stihl parts were confirmed. Original carb is stamped “China” on the bottom. Glad I didn’t waste money on a “Stihl” original part thinking I was getting something superior.

New carb arrives tomorrow, so we’ll see if that was it.

Finally, the Deep Creep marinade worked on the spark arrestor. It was a little sooty, but was definitely not clogged to the point where this was the issue.

Grouse

Carburator cleaner works ok and most of the time but soaking it overnight in a can of carburetor cleaner then blown out with air works wonders for a deep clean, I bought an after market carb for a small engine and it worked fine, but had to drill a lower access hole in the weed whacker plastic housing to get at the idle screw, The new carb idled to low right out of the box, a 1/4 turn and it idled fine. The high and low speed screws didn’t need to be touched.

Mechanical victory is mine.

Ordered this complete generic Stihl carb from Amazone for the princely sum of $16.99 and it arrived in 1 day.

Took 5 minutes to install with all new gaskets provided, it was virtually identical to Stihl’s Chinese-made original carb. No substantial difference.

Added gas, a few pumps on the prime bulb, off she went on the second pull. Standard settings the carb came with were good enough to get it running, so after a warm-up, it took a few minutes to tweak her to perfection.

Terrific fix. Would strongly recommend it if you’re mechanically inclined enough to remove the old carb.

Thanks for all the replies on this one, appreciate all the help.

Grouse

Hey hemi you seem to have the knowledge in these small engine repairs I’m trying to find the generic carburetor for a stihl fs91r but they seem impossible to find so if you can point me in the right direction I would really appreciate it

This is a pretty old thread. I’d pm hemi directly and refer to this thread and original posting date while asking him this question.

A simple google search found this on Amazon for $13.99
Carbhub Carburetor for Stihl FS90 FS100 FS100R FS110 FS110R FS130 HL90K HL95 HL100 HT100 HT101 HT130 KM90 KM100 KM110 KM130 SP-90 Carb Replaces Zama C1Q-S88 C1Q-S110C

Mikey wrote:

Hey hemi you seem to have the knowledge in these small engine repairs I’m trying to find the generic carburetor for a stihl fs91r but they seem impossible to find so if you can point me in the right direction I would really appreciate it

bigcrappie wrote:

A simple google search found this on Amazon for $13.99
Carbhub Carburetor for Stihl FS90 FS100 FS100R FS110 FS110R FS130 HL90K HL95 HL100 HT100 HT101 HT130 KM90 KM100 KM110 KM130 SP-90 Carb Replaces Zama C1Q-S88 C1Q-S110C

Wow. You have the unicorn of all trimmer/brushcutters. Can’t find a single carb listing that lists to fit FS91. And of course Stihl hides their parts lookups so no info available.

Using an educated guess, I see lots of carbs available for the FS87, which is the same engine size as the FS91 (28.4 CC).

I would buy one of these carbs on Amazon with the thought that if it doesn’t appear to be an exact match when you get it, you can always return it.

Grouse

Had issue with Stihl FS46C weed wacker. Ran rough and hard to start. Eventually found OEM carb on
Amazon and decided to try it for only $20. It was easy to replace and it magically fixed the issue and it’s running as if it was new.
Was hesitant when dealer stated that I shouldn’t trust these and they could cause more issues. I figured it was worth the attempt since it would cost more to have them fix it and since it’s over 6 years old I said what the heck and bingo it was a good decision.

Since this thread just came up again, I’ll update the experience with the generic replacement of my Stihl blower carb.

Almost 2 years to the day after I replaced the carb with the generic replacement listed above and the machine is still running great. It starts easier than when it had the OEM carb on it and I’ve never had any issues with it returning to idle. I have never adjusted the carb since I tweaked the settings after install 2 years ago.

A terrific and easy fix for less than $20. I am 99% sure this carb is coming from the Chinese factory that makes Stihl OEMs. Every casting mark and every line is the same. China is stamped in the same place on the bottom of the carb. Only thing missing is the “Stihl” stamp on the bottom.

I have since used generic carbs on a Tecumseh snowblower, a Briggs mower engine, and a Stihl chainsaw. Every one of them has been flawless and they run great, no trouble even on initial startup, they seem to have a “standard” setting pretty well figured out for the engines I’ve done. Only minor tweaking required and the 4 strokes are a matter of turning 1 screw.

I may be done rebuilding carbs for common small engines, I cannot see any value in it with these generics available for less than $20 each.

Grouse

As this is an older thread I needed a new carb for my Kicker Yamaha T8 Yamaha was nuts for the price found one on Aliexpress from
8 HP Yamaha they asked for pictures of my carb to see if it would fit and they said it would. It came fit perfect actually has an accelerator pump this T8 has never run better in it`s life for $69 delivered.