Question about Stihl FS 85 Weed Eater

1 Answer

Fuel in exhaust

How to find inlet needle

Posted by Anonymous on

1 Answer

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points


    An expert that got 10 achievements.


    An expert that got 5 achievements.

    Vice President:

    An expert whose answer got voted for 100 times.

  • Master
  • 381 Answers

You will find the needle-valve inside the the Carburetor reservoir bowl. Just be sure that the bowl is free of any dirt before putting it back together.
Good Luck
Rich Lilja

Posted on Sep 04, 2016

1 Suggested Answer

  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

a 6ya expert can help you resolve that issue over the phone in a minute or two.
best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.

Posted on Jan 02, 2017

Add Your Answer

Uploading: 0%


Complete. Click "Add" to insert your video. Add



Related Questions:

1 Answer

Fuel leaks from carb after mowing till tank empty

Most often this is caused be an inlet needle in the carburetor not seating.
1) The inlet needle itself can be at fault
2) The needle seat can be damaged
3) Dirt/debris/foreign object caught in the needle seat can hold the needle open causing a syphon effect
4) Debris/foreign material in the fuel can be transferred to the tank
5) Best to use plastic fuel can

Feb 15, 2017 | Garden

1 Answer

Throwing black smoke and back fire on 1986 nissan hardbody

black smoke is a sign of over fuelling ( leaking injector washers, excessive fuel pressure , choke on float not working needle and seat not shutting off,. This will also cause back firing as the fuel is accumulating in the inlet manifold and being ignited by an exhaust valve opening

Aug 14, 2014 | Cars & Trucks

1 Answer

Motor coughs and splutters upon acceleration

Hi Anonymous, if you have a carbuerator the usual suspects are:
1. Damaged or restricted fuel tank venting system (gas cap).
2. Inlet system air leak.
3. Vacuum piston malfunction.
4. Accelerator pump leaking or no output.
5. Plugged bowl vent.
6. Fuel level (float chamber) too low.
7. Restriccted fuel supply passages.
8. Plugged jets or passages.
9. Worn or damaged needle or needle jet.
10. Enrichner valve not seated or leaking.
Please visit the website below for a prime suspect:
Big Twin Carb EFI DTC Intructions codes Harley Davidson Forums Harley... Good luck

Feb 09, 2014 | Harley Davidson Motorcycles

1 Answer

What causes the engine to sputter when accelerating?

Hi Kallmeyer, and the usual suspects are:
1. Throttle cables misaligned or misrouted (may also affect idle speed).
2. Damaged or restricted fuel tank venting system.
3. Inlet system air leak.
4. Vacuum piston malfunction.
5. Accelerator pump leaking or no output.
6. Plugged bowl vent.
7. Fuel level in bowl too low.
8. Restricted fuel supply passages.
9. Plugged jets or passages.
10. Worn or damaged needle or needle jet.
12. Enrichner valve not seated or leaking.
For more information about your issue please visit the websites below. Good luck and have a nice day.
Victory Motorcycle Service Repair Manuals Page 2

Dec 09, 2012 | 2006 Victory Touring Cruiser

1 Answer

2004 crf450r dumps gas out of carb when gas is turned on

your float settings inside your carb are set wrong read my advice to resetting them and you should be ok
You'll need to first start off by removing your carb. Be sure to clean the surrounding area to the best of your ability to avoid dirt and debris falling into your carb; or worse, your engine. After you've removed your carb I would suggest a thorough cleaning using carb cleaner (or equivalent) and compressed air to ensure that all jets and passageways are spotless. Avoid using wire or other tools to clean orifices of jets; it's all too easy to alter their original designed dimensions.

After your carb is clean you can now set your float level. The picture below will allow you to become familiar with the parts that are responsible for maintaining the correct float level in your carb. There are four basic parts, the floats themselves (part of the float assembly), the float assembly tang, the fuel inlet needle valve, and the fuel inlet valve seat.

(Float assembly pivot pin not shown.)

It is always a good idea to remove the float assembly pivot pin (already shown removed) and extract the float assembly and the fuel inlet needle. The fuel inlet needle is a wearable part and over time can deteriorate. A worn fuel inlet needle can contribute to an irregular float level. Most fuel inlet needles consist of an internal spring loaded bumper (which contacts the float assembly tang) and a plastic or Viton (rubber) tip. Inspect the fuel inlet needle tip for wear and/or damage. To give you an idea, Eric Gorr recommends replacing the fuel inlet needle/seat assembly every two years. I've found that the average cost is around $15 for both parts.

(Fuel inlet needle shown with Viton (rubber) tip. The Viton is used to isolate the fuel inlet needle from vibration and to create a better seal against the fuel inlet valve seat.)

Now that you've made sure you aren't going to have any issues from worn parts you can reinstall your needle, float assembly and float assembly pivot pin and continue on to set your float level. The float level measurement is taken from the top of the floats (when the carb is positioned upside down) to the gasket surface of the float bowl as illustrated in the next picture. You can use an open-end wrench (sized per your spec), a small metric ruler, or a float level gauge. The tolerance for your float level is usually around +/- 0.50mm.


When setting the float level be aware that the spring loaded bumper on the fuel inlet needle valve may have a tendency to compress under the weight of the float assembly which will skew your measurement. Before you obtain your measurement you'll need to make sure that the float assembly tang just barely makes contact with the spring-loaded bumper. Sometimes it is easier to hold the carb body at a 45-degree angle to avoid compressing the spring in the fuel inlet needle.


If you find that your measurement does not match your float level spec then you can carefully bend the float assembly tang to achieve your desired measurement. Be sure to recheck your work, and if you feel confident that your float level is spot on then you can reinstall your carb and get back to riding.

Jun 20, 2011 | 2004 Honda CRF 450 R

1 Answer

Chokes down after running about 30 minutes. Will sometimes restart after several attempts and minutes but usually chokes down again within few minutes. I have changed the air and fuel filter, spark blug,...

There are few things that will make the engine run rich, one is the fuel inlet needle in the carb leaking, and the other is a blockage in the exhaust or spark arrestor.

May 14, 2011 | Garden

1 Answer

On my 99 honda 400 4x4 foreman gas pours out of the line at the bottom of the carburator when i turn the gas on what is wrong

The needle and seat are leaking. Check that there in no dirt or grit making the needle stick. Hold the carb cover upside down and **** lightly in the fuel inlet, if you detect any leakage, replace the needle and seat. Also check that the float has not become saturated or filled with fuel so that it does not lift the needle to shut off the fuel inlet.

Feb 25, 2011 | Honda CB 400 Four Motorcycles

1 Answer

My Craftsmand lawn tractor seems to load up with gasoline in the cylinder when sitting over night and then the starter can't turn it when I hit the key. If I let it sit a minute or so and hit the key it...

The needle and seat in the carb is not seating when the float level is high / float bowl full.

This is from the B & S Carb service manual:

An engine that exhibits leakage after it sits for a period of time can be caused by a number of problems. The most common of these is dirt. Any imperfection on a needle or seat surface, such as a small particle of dirt, can cause an engine to perform well in all other scenarios but still leak after sitting a period of time. In addition to dirt, an improperly vented fuel cap can allow pressure to build in the tank which could overcome the float assembly and result in a sporadic leak.

When an engine is not in use, the fuel in the bowl is exposed to the atmosphere via the bowl vent. Fine
particles of dirt or debris that normally would be suspended in the fuel and pass completely through the carburetor, settle out and end up at the lowest point between the fuel inlet fitting and the inlet needle. As the fuel slowly evaporates, the float responds by lifting the inlet needle very slightly off its seat. The dirt present moves in and lodges itself between the needle and seat. Now a slow but steady flow continues into the bowl, eventually showing up as a static leak.

These are the 2 most common causes of carb overflows.

Before replacing any parts attempt to clen the needle and seat area first by removing the float pin and dropping the float down so that any debris can be flushed out.

A new needle and seat is cheap and can be purchased at every lawn mower repair and parts supply. If you do change the needle valve make sure to tke the extra step of removing the old seat and replacing it. The rubber seat gets hard and the leaking overnight symptom can manifest itself again sooner than you might expect.


Thanks for choosing Fixya.


Aug 28, 2010 | Craftsman 20 hp 42 in. Deck Lawn Tractor -...

2 Answers

Flooding walbro carb from blower.

The problem centers around the carburetor. The question lies in the condition and operation of the carb initially.
It appears you may need to double check your assembly of diaphragms and gaskets. check for loose welch plugs, adjustment needles in the wrong holes, inlet needle set too high.

*note: metering side diaphragm goes on top of the gasket, fuel pump diahragm has the gasket on top of it.

Nov 10, 2009 | Husqvarna , No.455 Rancher, 20" Gas -...

3 Answers

Riding lawn mower keeps flooding

It sounds like the inlet needle seat is not closing all the way,allowing fuel to overfill the carburetor.The inlet needle seat may have dirt in it.You will have to remove the carburetor bowl and check for dirt or debris in bowl,if so remove the float assembly and check for a peice of dirt between the inlet needle and seat.If there is none you may have to replace the carburetor or rebuild it with a carburetor kit.You should also chang the engine oil because the overfilled carburetor drains to the crankcase,filling it with fuel,check the oil level and see if it is high,that would indicate fuel is in the oil.Hope this helps

Jul 28, 2009 | Craftsman 20 hp 42 in. Deck Lawn Tractor -...

Not finding what you are looking for?
Stihl FS 85 Weed Eater Logo

Related Topics:

79 people viewed this question

Ask a Question

Usually answered in minutes!

Top Stihl Garden Experts

Joseph Mueller
Joseph Mueller

Level 2 Expert

338 Answers


Level 1 Expert

5 Answers

ray gallant

Level 3 Expert

41407 Answers

Are you a Stihl Garden Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides