Shop wants to replace carburetor--is it necessary?

[cutter44752]

My saw is in the shop for a number of issues addressed in a different thread (mainly the oiler hole clogged leading to smoking of the chain).

They also said the carburetor needs to be replaced as it doesn't idle properly, the only thing I've noticed is that when I start it up it immediately revs all-out but I just pull the trigger and it goes back to a normal idle...I feel like they just want to do a $110 repair but I'm not technical enough to take the carburetor apart and clean it out myself I don't think (but they say it's a "safety issue"). Any thoughts?

 

[hotajax]

Just saw your post, hang in there. There's some sharp guys on here and you will get your answer in a short time. I am NOT the guy to take a shot at this problem, believe me.

 

[Chevboy0167]

It's referred to as high idle on start up. Normal. If you have the owners, it should explain when and why it does this.


If you need an owners manual, go online and download one from Echo website or a general search on google. I recommend from the maker of your saw first.

 

[Homer6679]

If what you say is true, you need a new saw shop to take your saws.

 

[Bob Hedgecutter]

Might be a case of the blind leading the blind- I doubt the carb needs replaced if the saw will not hold an idle that allows the chain to come to rest (only safety issue)- but the clutch on the other hand, that I could understand.

 

[Cliff R]

It is always best to clean the OEM carburetor and install new OEM parts in it vs replacing it. In all the years Iof working on carburetors (full time for over 20 years until retiring recently) I've only had to replace a very small percentage of them and that was only due to something breaking on them, may years of sitting with bad fuel in them, or heavy rust/oxidation from leaving them exposed to the elements for some reason.

I'm not sure eactly why but I see a LOT of folks ditching their OEM carburetors when they have issues with their small power equipment. Most buy cheap Chinese replacement carburetors as in most cases an original OEM carb is going to be as much as 3-4 times more costly. I've had ZERO luck here with any of that so always stick with OEM, which is what I'm recommending here.

I'll add here that most carburetor issues are going to be fuel related. Chainsaws typically sit for weeks, months and even years between uses. If you don't dump the tank and run them empty there is going to be a good chance the fuel will go bad and clog things up. This new fuel is also really hard on rubber, neoprene, nitrile and other materials carburetor parts use and require to function correctly. It will even "eat" many fuel lines even if they are dubbed to be made from ethanol friendly materials.

Getting to the point, in at least 95 out of 100 cases all that is needed if/when you have carb issues is to take it apart, clean things up, and install the correct OEM rebuild parts in it. Dump all the old fuel at the same time, check the filter, fuel line, and tank vent. Then install the carb, fresh fuel mix and good to go.....

 

[Bill G]

If what you say is true, you need a new saw shop to take your saws.

Ah yeah

 

[ZeroJunk]

I usually replace several carbs a week. The only ones I rebuild are the ones that are NLA new.

On average it works out better. Any body who wants it any other way should take it to another shop.

Matter of fact, I wish they would.

 

[Bill G]

I usually replace several carbs a week. The only ones I rebuild are the ones that are NLA new.

On average it works out better. Any body who wants it any other way should take it to another shop.

Matter of fact, I wish they would.

I do not believe what he described is a carb issue.... a inept tech issue.

 

[stihltech]

OK magic wand out of order.
What saw, make, model, age, carburetor model, etc.
A lot of reasons to cause issue. Need diagnosis.

 

[Cliff R]

We've become a "replacement" society which means that this and next generation are failing to learn the skills sets required to actually fix anything.

In at least 95 if not more cases missbehaving OEM carburetors do NOT need replaced. Even if you do using those cheap Chinese copies is NOT a good route to take....IMHO

Nothing at all wrong with going to OEM, however we are seeing a LOT of the OEM carbs disappearing from the catalogs. This mandates rebuilding what you have, or finding a good donor carb from another saw of the same model.

Same with a lot of other things, including P/C's. I refuse to use anything but OEM. In the big scheme of things it simply works out better for your reputation and your business.

You also have to pick and choose your battles when you are in the business of repairing small power equipment, or many other things these days. IF the customer dumps a saw on you, for example, which is/was nothing but a big piece of bovine excrement right out of the box, you either need avoid getting involved with it. If you do, and charge them prevailing labor rates, you will very quickly find yourself "married" to them, because every single time that POS refuses to do what it's supposed to you are going to get it thrown right back on your counter with the customer quickly reminding you that........."ever since you worked in it it's" doing this or that, etc.....FWIW....

 

[Roadkill17543]

The most likely cause is a vacuum leak which a new carburetor wouldn't help at all. The crank seals which you can find for $20ish. That requires you to take the saw completely apart though.

It's probably the easiest to test for though. All you need is your saw running and an aerosol can with a spray tube. Spray some around the edges of the flywheel and the clutch. The saw will either idle faster or slower depending on the flammability of your Spray. If the idle speed changes you need new seals.

If not you can do the same test around the intake gasket. You will want to be careful not to allow any to get it threw your carburetor though. Or your results will not be accurate. If it's the gasket it is an easy fix. However if it is the crank seals. I would recommend that you find a new shop and inform them that you suspect a vacuum leak. That will give them a starting point.

 

[Okie]

Now days about your saw you can go on-line and gets lots of info (you tube how to's) and the price of a carb kits, replacement clone carbs, etc.

I know nothing about your other thread but smoking chain may require a replacement bar and chain and the oiler section repaired then a replacement carb. Might be time to quit throwing good money into bad before it gets worse if you cannot complete the repairs yourself. A good repair tech would have checked the operation of the saws power head BEFORE doing a oiler repair so as to give you a up front estimate of repairs needed before just jumping in feet first costing you money.

Some of the things you mention is why I started repairing my own stuff several years ago and now days use of the computer and site info like this one makes info more readily available.

Post up a link to your other thread about your saw.

 

[Automender]

It seems like everyone jumped to a conclusion on just what the shop is saying about the idle. The poster said the only thing he noticed was a fast idle at startup but he did not say the shop claimed that was the issue. And the poster self proclaimed he isn't that technically knowledgeable. Hate to have you guys as jurors in a court case. He should ask the shop why they think they need to replace the carb and post that reason. Then people can jump on the shop bandwagon.

 

[Cantdog]

A couple years ago I suddenly found myself in need of carb kit (RK 23 HS) and found my stock was depleted. I usually keep at least a half dozen in stock but the last got used before I could re-order so I was in a bind and bit the bullet and drove 15 miles to the local Stihl dealer and paid the usual $15-$16.00 for the kit.....got back to the shop and then noticed it was not the full kit but the minor kit......now I got 30 miles in the trip and looks to be 60 before I get what I need. I called the shop owner (whom I've known for many years) and said you gave my the short kit instead of the full kit. He said "That's all I carry.....if that don't fix it the saw gets a new carb...simple as that." His reasoning was at the hourly shop rate he charged it was not cost effective to thoroughly rebuild a carb.......cheaper for the customer to replace with OEM new....even at Stihl prices!!

 

[ZeroJunk]

I have no idea whether there is anything wrong with OP's carb or not.

Usually what you run in to is they get a bugger in them from sitting. Or, they won't prime.

By nature, the older carbs that are NLA are the easiest to rebuild. And, you can make them like new.

New fixed jet no adjustment carbs are like chasing your tail.

Most volume is in little hand held blowers and home owner weed eaters. The OEM carbs are $45 or thereabouts and I'll put it on for $10. So, if a kit is $15 and might not fix it and 1/2 hour labor. What have you got.

Now, I will rebuild the carbs on the old Stihl square back packs because the price on those carbs is insane for some reason.
Also, if a carb won't prime because the check valve in it is bad somebody explain to me how they fix it and doesn't take more time than it's worth. I am actually curious about that.

Sorry, I know this was not a carburetor thread.

 

[cutter44752]

It seems like everyone jumped to a conclusion on just what the shop is saying about the idle. The poster said the only thing he noticed was a fast idle at startup but he did not say the shop claimed that was the issue. And the poster self proclaimed he isn't that technically knowledgeable. Hate to have you guys as jurors in a court case. He should ask the shop why they think they need to replace the carb and post that reason. Then people can jump on the shop bandwagon.

Good point, I just called them and they clarified that it doesn't come back to a low idle after being revved, this wasn't happening before so I told them I was just going to pick it up and see how things went for me. Sounds like maybe they messed with the idle while taking it apart, if it happens to me I'll look into how to adjust it myself when I have time.

 

[Bob Hedgecutter]

It seems like everyone jumped to a conclusion on just what the shop is saying about the idle. The poster said the only thing he noticed was a fast idle at startup but he did not say the shop claimed that was the issue. And the poster self proclaimed he isn't that technically knowledgeable. Hate to have you guys as jurors in a court case. He should ask the shop why they think they need to replace the carb and post that reason. Then people can jump on the shop bandwagon.

If you had read the previous thread on the same saw- you might have figured out most of the relevant evidence regarding the pooched saw, owners lack of experience in diagnosing problems and the suggestions of vacuum and pressure testing there.
Plus this thread- shop wants to replace carb for a "safety issue" only issue that can be regarding idle can be the chain failing to come to a stop- which is very likely NOT anything to do with the carb, so like I said above, it is a case of the blind leading the blind- the people at the "shop" (lets not call then technicians or small engine mechanics) are the ones you do not want sitting on your Jury benches.

 

[stihltech]

The biggest question is why is the diagnosis carburetor? What else was checked?
We have a two page check sheet from Stihl. The idea is to use it enough that it is in our brain.
Even if I do conclude a new carburetor (usually due to price as stated before) vacuum and pressure test must be used to rule out all other issues.
Without it, you really do not know if you will cure the issue.

 

[Automender]

Good point, I just called them and they clarified that it doesn't come back to a low idle after being revved, this wasn't happening before so I told them I was just going to pick it up and see how things went for me. Sounds like maybe they messed with the idle while taking it apart, if it happens to me I'll look into how to adjust it myself when I have time.

Get it home and post a video of the issue, be careful on the chain if it is indeed rotating. You can back down the idle mechanical set screw. Also if the idle mixture is set too lean it can also cause a high idle speed that can't be overcome with a mechanical idle screw. A intake leak will also cause a idle that can't be be compensated for. Since I didn't connect this to your previous thread I am not sure if there are any EPA limiters on your carb.