Stihl 025 oil pump help (1 Viewer)

[Anand]

Thank you.

I am not sure if I made myself clear when asking my question, the gap is between the sprocket and E clip, meaning on the shaft and not between the clutch and the sprocket drum. So, the sprocket moves back and forth on the crankshaft. Is this okay too ?

 

[D'Animal]

It heats up by the clutch slipping inside the drum. As the drum heats up, the OD expands. As the heat works through the drum itself then entire metal mass will be larger. As the "toothed" part of the sprocket (where the chain engages) heats up, it will expand along the axis of the crankshaft. = The gap between the sprocket and the washer and clip is reduced.

This takes about 1 or 2 cuts in the piece of woood for all of this to happen.

If there was no gap, it would bind up and turn into a direct drive.

 

[Anand]

The most eloquent answer ! Thank you very much for clearing up my doubt.

 

[Anand]

Hello D'Animal...thus far with your help I have been able to put the oil pump back together. At least it stopped leaking oil from the bottom of the chainsaw. I have replaced the oil line, the o-ring on the plastic pump connector and the worm gear. So, its all ready to test.

I have encountered another problem. The chain saw starts but does not idle. And dies when I give it throttle. I read the other posts where you have discussed and suggested removing the blade and chain and trying to see if it runs. I tried this and it still does the same.

I have removed the carb and cleaned it (did not soak it).
When I opened it up I saw that there was fuel on the metering side (where the needle is).
The diaphragm looks is good shape.
The hole in the jet is clear.
Cleaned the other side of the carb with carb cleaner spray.
Don't know how to and don't have the tools to open the welch plug on the carb. So, baring that I have cleaned all ports with carb spray.
There was some floating debris it he tank after I put back the carb, so I went ahead and cleaned the tank and removed the fuel filter and blew compressed air in the opposite direction to clear it and put it back.
There is no carbon in the exhaust part, its all clean.
The muffler itself was cleaned and the spark arrestor is clean.
Fuel Hose has no leaks and looks good.
Removed the carb again since I found this debris in the tank to clean it again.

Can you please suggest what else I need to do. Just FYI this machine has sat idle for about 2 years. Eagerly waiting for your reply.

 

[D'Animal]

Is it hard to start or does it start right up?

 

[Anand]

A little hard to start. I have to give it the choke and after 2-3 tries on the choke, it fires up. Then I remove the choke and 1-2 tries it starts and runs for a few seconds and stops. As the throttle is opened it immediately dies.

 

[e9999]

A little hard to start. I have to give it the choke and after 2-3 tries on the choke, it fires up. Then I remove the choke and 1-2 tries it starts and runs for a few seconds and stops. As the throttle is opened it immediately dies.

had one do something somewhat like that (more specifically it would start on the choke but when I shut down the choke it would stop) not too long ago and if IIRC it was a rubber line between carb and primer bulb that had a crack. Had one do the throttle = dies bit too a while back. I think that one was more complicated. Forgot what I did.
Anyway, D' will know

 

[D'Animal]

What are your H and L screws set at on your carburetor?

 

[Anand]

Honestly I don't know what the High and Low Idle are set at. I have not set them in the past. Incidentally this is a Walboro WT 283B carb also the number 744 is imprinted on it. As the picture below shows, it has only one screw to adjust both High and Low idle. The other screw in the pic. is a Idle adjustment screw.

If you want me to set this, please educate me on how to go about doing it.

 

[D'Animal]

Remove the meter cover and diaphragm. It is the cover with 4 screws holding it on. Make sure the welch plugs are firm. You can re-seal them around the edges with Seal All. It is a type of superglue that is impervious to ethanol and other chemicals. Some use fingernail polish but I have not found it to work with the fuels we are getting today. Reassemble the carburetor.

In your top picture, turn the screw to the right until it lightly seats. Back the screw out or turn to the left 1 - 1 1/4 turn out.

Reassemble the unit.

Make sure the master control switch is working properly. It is common for the person working ont he unit to tweak the metal rod on the left side of the master control switch and it will hang up the choke lever.

 

[Anand]

Thank you for the detailed advice. I have done exactly what you recommended and the problem is not resolved. It runs for a little longer than before. The minute I give it throttle or let it run (idle) on it own for a few seconds, it shuts down.

I have tried both 1 and 11/4 turn and also went up to 11/2, 13/4 and 2 turns. The problem remains.

Can you please suggest as to what else I need to do to resolve the issue.

 

[fj40charles]

Thank you for the detailed advice. I have done exactly what you recommended and the problem is not resolved. It runs for a little longer than before. The minute I give it throttle or let it run (idle) on it own for a few seconds, it shuts down.

I have tried both 1 and 11/4 turn and also went up to 11/2, 13/4 and 2 turns. The problem remains.

Can you please suggest as to what else I need to do to resolve the issue.

You might need to put a carb kit in it. Usually replacing pump and metering diaphragm is all you need.

Did you make sure the impulse and fuel line hoses are free from leaks?

 

[D'Animal]

It is running lean in the midrange of the carburetor. The lever for the inlet needle may be set too low or you may have debris in jets of the carburetor.

The most common problem is you have a crack in the fuel line allowing an air leak into the fuel system. You stated you already pressure tested it and it does not have a hole in it.

The white plastic elbow on the craburetor that the fuel line plugs into should not be loose.

You may have a crack in the impulse line. It connects under the orange handle housing directly under the carburetor. The other end of it connect to the lower crankcase.

 

[Anand]

Thank you. Thank you both. I think I will lean with 'D''s recommendation. When I said I had checked the fuel line, I did not pressure test it. It was more of a visual check to see if I had any leaks.

- Please tell me how to go about doing a pressure check on the line.

- Also please tell me as to what I need to do with the impulse line, how to check ?

I read about the inlet needle,

This is a passage from another article on the net, which confirms what you say....

" This is the single most critical setting on a Walbro carb! Walbro offers a "setting gauge" to properly set the height of the lever for your particular carb. If you don't have one, the setting will be a trial & error adjustment and a real pain in the **** since you have to open up the carb to make the adjustment. For general purposes, the lever will be almost perfectly parallel to the carb base. This will get you close. If the lever is too high, your engine will tend to run a little erratic at idle. If the lever is too low, your idle will be OK but it will tend to run lean on midrange and highend. It may also run the float cavity "dry"; at full throttle and die, regardless of your highspeed /lowspeed needle settings. "

- Do you know of or have a procedure to set the inlet needle without a special tool ?

- I will clean out the jets and carb

- The white plastic elbow is not loose and does not leak fuel, but is discolored.

Thanks again for your patience with me.

 

[Anand]

I think your first guess was right. The fuel line did not have any leaks, but I found a soft spot at one place and decided to replace the fuel line. The Impulse line, I tested and did not have any cracks or leaks. The rubber has become a little hard from age, I guess. So, I looked at the needle setting and obviously like you said, it was on the lower end. So this time I cleaned the carb again, and set the needle as they said in the paragraph above .... same level as the base of the carb. And the results..... It works like a charm !! I have not installed the blade and chain. But the oil starts to come out the minute I release the brakes. I will do the finally assembly tomorrow and run it again and let you know. I currently have the carb set at 1 1/4 turn. Should I set it at 1 instead. I notice a bit more smoke from the exhaust.

 

[D'Animal]

Put the bar and chain on the saw and run it to check preformance. Adjsut the carburetor for best performance in throttling up as well as power in the cut.

There is nothing you can do as far as adjustments to the saw to reduce the smoke. The smoke is coming from the oil in the fuel. Some oil smokes more than others, some is smokeless oil, some people put too much oil in the fuel.

Do Not adjust the carburetor based on how much smoke is coming out the exhaust. You will sieze the motor.

 

[Anand]

Thank you again. I did what you suggested and it runs great !!

I am using the Stihl oil. Is there any other brand you can suggest that is lower in smoke ?

Also, my exhaust muffler on the 025 stihl has a small hole due to rust.

If you or anyone out there has a used exhaust muffler for sale that goes on the 025 Stihl chain saw, please let me know.

Thanks a ton for all your help Dan !

I may have one last question in regards to order of parts on the brake handle. I will write in my next post.

 

[fj40charles]

Thank you again. I did what you suggested and it runs great !!

I am using the Stihl oil. Is there any other brand you can suggest that is lower in smoke ?

Also, my exhaust muffler on the 025 stihl has a small hole due to rust.

If you or anyone out there has a used exhaust muffler for sale that goes on the 025 Stihl chain saw, please let me know.

Thanks a ton for all your help Dan !

I may have one last question in regards to order of parts on the brake handle. I will write in my next post.

The best oil to use is Stihl HP Ultra. This is a full synthetic oil. Comes in a white and/or grey container.
http://www.stihl.com/isapi/default....e-zubehoer/betriebsstoffe/hpultra/default.htm

The engine piston, cylinder, rings, crank bearings, and wrist pin bearing are lubricated by the 2 cycle oil. You have an engine turning 13K+ RPM. Don't think I'd trust my engine to any inferior oil.

 

[D'Animal]

Is your saw is still smoking after you have ran it for awhile?

In theory, after sitting awhile, the fuel will evaporate from the fual can and leave the oil sesidue behind. When you add the fresh mixed fuel you are blending the oil residue and the mixture may be a bit more than anticipated during intial start up.

or

You mixed the oil and fuel at an incorrect ratio.

Also, my exhaust muffler on the 025 stihl has a small hole due to rust.

If you or anyone out there has a used exhaust muffler for sale that goes on the 025 Stihl chain saw, please let me know.

There is a muffler on this parts chainsaw that is the same one you need.

https://forum.ih8mud.com/mud-bay-mi...0-trade-sthil-power-equipment-parts-saws.html

 

[Anand]

It smokes a lot less after start up. But if I open throttle to full then I see a bit of smoke. Thanks for the lead on the muffer. I posted a question to him. Even though its a MS 210 will the exhaust muffler work on a 025 ? Thank you.