On the same issues with similar carbs. Stihl notes in their repair literature to perform vacuum and pressure tests when rebuilding the fuel delivery system. Worn shafts will likely fail the leakdown test. Your method is a quicker and simpler way to avoid spending time with a carb that is too far gone to begin with a carb rebuild. The expense of a new shaft would be wasted on a worn, wallowed out hole in the block. Again, metal recycling bin! Thanks again... your lesson is worth it's weight in gold.
Good demo video, explanation and the rationale for the replacement carb. Rebuilding kits are of no value if the shaft is worn out. Thanks for another quality lesson and insight on carb vacuum leak potential!
Thanks for this one, Jeremy! Tiller wouldn't keep a tune so I did a pressure/vac test and the throttle shaft leaked out fuel! This is the first time I've ever replaced a carb (Hipa kit) and after reassembly it started up immediately and took a perfect tune really easily! I didn't need all the other junk in the carb kit, but I'll put the odds and ends into my parts inventory and make more $ with them in the future.
Thanks for the quickest way to diagnose these. I have wasted quite a bit of time trying to get them dialed in, thinking that that little bit of slop wasn't a big deal. I've taken a wrap or two of Teflon tape to get the slop out , thinking that it would stop any air from messing up the dynamics of the flow. Metal recycling can from now on!
I have a Zama C1Q S57B carb on a 2011 Stihl MS180 chainsaw that seems to be flooding the engine even when cranking off choke. All the carb components looked great, and new C1Q S57B carb rebuild kit did nothing to resolve the problem. The saw will not fire at all with the carb mounted because of immediate flooding with any cranking. If I remove the carb, dry out the crankcase and cylinder, then drip a little fuel into the crankcase through the open intake port, it will fire nicely after about five cranks, rev way up, then die out as soon as all the fuel burns off. The engine is a brand new replacement build after an earlier lean running piston burnout from an air leak in the furl line. The new engine has rock solid pressure and vacuum, and about 125 PSI COMPRESSION. The C1Q carb is Stihl OEM with no visible metering abnormalities, crud, or loose butterfly shafts. I suspect a bad main jet check valve, but manual suction check suggests that the valve is working normally. The fuel needle holds solid pressure when closed and opens normally with metering valve depression. I can’t figure out what in the world is flooding my engine with any simple closed system cranking. I’m waiting on a cheap cloned carb replacement but I’m deathly afraid I’ll have the same problem with a new carb. Any suggestions??? drdrdaddeo@Comcast.net. P.S. Really appreciated your excellent video. Dr. K.
Great video, really enjoyed it. I admit that I focus on the diaphragms and gaskets, and other components when having perceived carburetor issues and never focus on what you have shown in this video and I thank you for that. One question: regarding the 4-stroke blowers like the BR600 and that family, what has been your experience using aftermarket carbs as replacements when the original wears out like what you have shown us here. Is it reasonable to use aftermarket vs OEM? Thanks again.
Another very helpful vid Jeremy. I had to change a shaft last summer and found the accelerator pump. I didn’t know it was there or what it was until your video. How does that pump work? Cheers
Hey Jeremy I have a question for you why is it some weedwacker carburetors even after. You rebuild them and pressure test them and they hold pressure still leak gas out of the throat of the carburetor after its ran for a few minutes. I have asked this at echo and stihl schools and can not get a good answer. I had a echo do this last week full rebuild kit polished the seat . held pressure on the needle valve. But after running it and letting it sit gas comes out the throat of the carb
Hi I just want to know To start the trimmer It does not starts . after spraying in the carb .trimmer runs good .you can stop the trimmer and start after few minute .it start right up do you know whey it is doing that what need to fix Thanks
I have g372xp and have lotsa air leaks think i go them attended but would like try Tillotson inztead of hd12b hear theyre good but cost effective please help if you can
Carburetors have gotten so inexpensive, I just replaced them now. Especially Honda carbs. I don't know whe their OEM carbs are so cheap, but I'm not complaining lol.
Thank you great tips I have In the passed had alot of trouble with zama walborough carburetors too I just think they're cheap and I think they're junk especially if you try to rebuild them nowadays you can buy them cheaper than you can rebuild them I think but they're all just Chinese junk basically
Had a question for you bud. I’m working on a co workers go powered pressure washer he had a carburetor that the gaskets had been rotted instead of a rebuild he just wanted a new carburetor so I got him one installed and it started running only on choke (a new issue) cleaned and rebuilt the old one no change still only running on choke the gaskets on the mounting studs are all new so I don’t think air leak. Any thoughts? Gx340
@@georgepruitt637 I actually got to the bottom of this some time ago the rubber tip on the end of the needle valve was swollen due to him letting it sit with ethanol you couldn’t tell looking at it until I got a new one so basically the bowl was never getting fuel it was just being sucked from the inlet into the main jet causing a lean condition
i cant tell you how many people including landscapers that constantly pull that throttle up and down as fast as they can the whole time they run the equipment ,, i guess they just like the sound of it reving up and down lol ...
No Spencer, I have a fs90r 4mix around 10 y.o. w/original carb . Never been rebuilt. Only thing I've repaired was replacing the string head. It'll start on the 2nd or 3rd pull every time. And it is hell on some honeysuckle vines 3/8 inch thick.
On the same issues with similar carbs. Stihl notes in their repair literature to perform vacuum and pressure tests when rebuilding the fuel delivery system. Worn shafts will likely fail the leakdown test. Your method is a quicker and simpler way to avoid spending time with a carb that is too far gone to begin with a carb rebuild. The expense of a new shaft would be wasted on a worn, wallowed out hole in the block. Again, metal recycling bin! Thanks again... your lesson is worth it's weight in gold.
That would explain issues I've had with those little carbs that I couldn't figure out. Thanks for the detailed explanation.
They use to call it water testing the carb. Good video on dianoising carbs
Good points. I'm guilty of overlooking throttle and choke shafts, bit me in the back side
Old hotrod trick , theyed wear we had em brass bushed w new shafts .been so long i forgot tho0
Good demo video, explanation and the rationale for the replacement carb. Rebuilding kits are of no value if the shaft is worn out. Thanks for another quality lesson and insight on carb vacuum leak potential!
Thanks for this one, Jeremy! Tiller wouldn't keep a tune so I did a pressure/vac test and the throttle shaft leaked out fuel! This is the first time I've ever replaced a carb (Hipa kit) and after reassembly it started up immediately and took a perfect tune really easily! I didn't need all the other junk in the carb kit, but I'll put the odds and ends into my parts inventory and make more $ with them in the future.
Good information, had never thought of checking those shafts for play
Thanks for the quickest way to diagnose these. I have wasted quite a bit of time trying to get them dialed in, thinking that that little bit of slop wasn't a big deal. I've taken a wrap or two of Teflon tape to get the slop out , thinking that it would stop any air from messing up the dynamics of the flow. Metal recycling can from now on!
Thanks for the new #1 item on my Carb checklist. I hadn't really thought of it except for when it's really obvious.
Thanks! I check the shafts, but never knew about the accelerator pump inside.
So appreciate all your content, explaining the problems and most importantly how to fix the problems.
Never thought of checking that.
I have a Zama C1Q S57B carb on a 2011 Stihl MS180 chainsaw that seems to be flooding the engine even when cranking off choke. All the carb components looked great, and new C1Q S57B carb rebuild kit did nothing to resolve the problem. The saw will not fire at all with the carb mounted because of immediate flooding with any cranking. If I remove the carb, dry out the crankcase and cylinder, then drip a little fuel into the crankcase through the open intake port, it will fire nicely after about five cranks, rev way up, then die out as soon as all the fuel burns off. The engine is a brand new replacement build after an earlier lean running piston burnout from an air leak in the furl line. The new engine has rock solid pressure and vacuum, and about 125 PSI COMPRESSION. The C1Q carb is Stihl OEM with no visible metering abnormalities, crud, or loose butterfly shafts. I suspect a bad main jet check valve, but manual suction check suggests that the valve is working normally. The fuel needle holds solid pressure when closed and opens normally with metering valve depression. I can’t figure out what in the world is flooding my engine with any simple closed system cranking. I’m waiting on a cheap cloned carb replacement but I’m deathly afraid I’ll have the same problem with a new carb. Any suggestions???
drdrdaddeo@Comcast.net.
P.S. Really appreciated your excellent video.
Dr. K.
Thank you.
Great info
Good explanation.
Stay safe, Joe Z
Good catch! I’ve Bushed hard to find carbs for chainsaw guys.
Great video, really enjoyed it. I admit that I focus on the diaphragms and gaskets, and other components when having perceived carburetor issues and never focus on what you have shown in this video and I thank you for that. One question: regarding the 4-stroke blowers like the BR600 and that family, what has been your experience using aftermarket carbs as replacements when the original wears out like what you have shown us here. Is it reasonable to use aftermarket vs OEM? Thanks again.
Another very helpful vid Jeremy.
I had to change a shaft last summer and found the accelerator pump. I didn’t know it was there or what it was until your video.
How does that pump work?
Cheers
Hey Jeremy I have a question for you why is it some weedwacker carburetors even after. You rebuild them and pressure test them and they hold pressure still leak gas out of the throat of the carburetor after its ran for a few minutes. I have asked this at echo and stihl schools and can not get a good answer. I had a echo do this last week full rebuild kit polished the seat . held pressure on the needle valve. But after running it and letting it sit gas comes out the throat of the carb
Ah vibration running problems, was going to say how many hours of use cause this wear.
I love your videos
What would be the best kind of fuel to use in Mowers and weedeaters, Blowers. ( Husqvarns ) troybilt
I’m not sure I understand the question are you talking about what brand of fuel?
Non-ethanol fuel, this will prevent you from inventing new cuss words.
@@THEMOWERMEDIC1 not exactly octane type. 87. 94 that type of fuel I was told nothing less than 87 octane
How do you feel about after market carbs?
Hi I just want to know To start the trimmer It does not starts . after spraying in the carb .trimmer runs good .you can stop the trimmer and start after few minute .it start right up do you know whey it is doing that what need to fix Thanks
Thanks for the information has stihl ever made any of there own carburetors?
Stihl actually owns Zama now so sort of.
Stihl owns ZAMA but has always used a combination of WALBRO tillotson and ZAMA over the years. Even seen some zenith carbs on the super old stuff
@@THEMOWERMEDIC1 Thanks for the reply Jeremy!
I’ve thrown out auto and truck carbs for same issues, just plumb worn out!
I have g372xp and have lotsa air leaks think i go them attended but would like try Tillotson inztead of hd12b hear theyre good but cost effective please help if you can
Carburetors have gotten so inexpensive, I just replaced them now. Especially Honda carbs. I don't know whe their OEM carbs are so cheap, but I'm not complaining lol.
Thank you great tips I have In the passed had alot of trouble with zama walborough carburetors too I just think they're cheap and I think they're junk especially if you try to rebuild them nowadays you can buy them cheaper than you can rebuild them I think but they're all just Chinese junk basically
Had a question for you bud. I’m working on a co workers go powered pressure washer he had a carburetor that the gaskets had been rotted instead of a rebuild he just wanted a new carburetor so I got him one installed and it started running only on choke (a new issue) cleaned and rebuilt the old one no change still only running on choke the gaskets on the mounting studs are all new so I don’t think air leak. Any thoughts? Gx340
Fuel filter plugged up
New but won’t hurt to check
Oem or Chineseum knock off
It has the original rebuilt on it now but I think the new one he got was knock off
@@georgepruitt637 I actually got to the bottom of this some time ago the rubber tip on the end of the needle valve was swollen due to him letting it sit with ethanol you couldn’t tell looking at it until I got a new one so basically the bowl was never getting fuel it was just being sucked from the inlet into the main jet causing a lean condition
i cant tell you how many people including landscapers that constantly pull that throttle up and down as fast as they can the whole time they run the equipment ,, i guess they just like the sound of it reving up and down lol ...
I just got a price of over $100 to get a BR600 carb from dealer. The one's on Amazon are $30.
Do you have an opinion on the Amazon carbs?
Hit or miss.
I pitch and replace carbs these days.
Was hear
Rub a little kerosene on the shafts, it'll fix'em right-up. Ha!!
THEMOWERMEDIC1 I guess stay away from STIHL 4-MIX?
No Spencer, I have a fs90r 4mix around 10 y.o. w/original carb . Never been rebuilt. Only thing I've repaired was replacing the string head. It'll start on the 2nd or 3rd pull every time. And it is hell on some honeysuckle vines 3/8 inch thick.
ev a bunch of bull