Carbuerator Overhaul on a Huskavarna 154 Se

[Auto Tech]

I had developed a severe stall condition especially when you tried to use high rpm jets. I bought a carb kit and overhauled the carb BUT lacked the information on settings internally BUT the carb did not look very complicated. I am a A class Ford Technition and have loads of experience on lawn tractors with B&S and Tucemseh but really have no experience with 2 cycle engines and carbs. I am also having trouble with chain stretch and my chain is only a few months old. BUT top item is low on power and dogging while cutting thick wood and Misquite. She alsways seems to need variances on fuel mixture as she is used and it should not need this one setting should do it. I live in Nm and cut wood daily with the saw for heat purposes. This saw is a critical tool for everyday while winter lasts.

Any help is appreciated..

[restrorob]

There is a small fuel in-let screen inside the carb., This screen get glazed over from fuel and restricts fuel flow. It is hard to see th glazing so should be sprayed out with carb. & choke spray cleaner. Als the fuel filter should be checked, These little engines must have a fre flowing filter with no restriction. Screw the adjusters in all the wa then back low speed out one turn, High speed one and a half turn. Thi is a starting point for fine tuning once started.

As for chain stretch, That is caused in most part from the chai getting in the dirt while cutting. Use a shovel or something to lif the logs little as an inch sliding something under to get it off th ground before cutting. Also if the chain is stretched badly check th sprocket for grooves, Grooves in the sprocket adds to chain stretc also. If there are grooves in the sprocket replace both sprocket an chain as a pair, Never install a new chain on a grooved up sprocket i will only cause the chain to stretch fast like you stated

-- restrorob

[Auto Tech]

Hi Restrob, I had that carb completely apart and saw no screen. I replaced it's needle and arm and diaphram and on the bottom I replaced the gasket and the floopy type diaphram that opened and closed ports and saw no sign of a screen. I looked and figured there had to be but did not see it anywhere and since the overhaul she is somewhat useable but lacks horse and her performance is lousy and needs twekaing all the time. I did start at 1 turn each screw for starting point and opened it from there. Like I said I have overhauled all brands of car carbs over the years but this timy little carb was new to me and if there is a screen hidden where is it ??

restrorob wrote:

[restrorob]

Hmmm, It should have been located under the diaphragm above the fuel inle needle (which is located in the center of the carb. body).

Can you post the brand carb. and the number stamped in it ?

Have you checked the spark arrester screen in the muffler ? These wil clog up from the fuel mix restricting exhaust flow and could cause a you describe also

-- restrorob

[Auto Tech]

Hi Restrob. Yupper i did and it had partial restriction so I did an old trick I learned long ago from the 2 cycle guy I worked with and set the muffler in gasoline and set it afire and it cleared out the partial restriction to a full flow again. The carb is a Walbro I do not recollect the number but if it helps here is the link to a carb list and it is for a 154 SE

Year of production 1984

is the number of thre kit rk22hda walbro carb kit

restrorob wrote:

[restrorob]

OK, From one Ex Auto Tech to a Present Auto Tech Below is a break-dow of your carb. and where the fuel inlet screen would be located, Eithe the top under the diaphragm or on the bottom under the fuel pump. As said it is hard to see the lacquer in the screen so spray it out goo with carb. & choke cleaner

+------------------------------------------------------------------- |Filename: Husky 154 Carb..jpg |Download:

[Auto Tech]

Hi Restrob, My pix I sent you did not show a plate covering a screen. Now I see why I did not see a screen. I hope I can save the plate for I do not have another. You have helped me a great amount and it now answers why she is so nasty running and needs constant fuel ratio changes and she has no hootsba ha ha ha ha ha balls if you will and she simply won't scream and still at times acts boggy. I am learning about

2 cycle the hard way.

Tom

restrorob wrote:

[ds549]

if you can tell me the carb make and model you have may be able to help. if the saw is a few years old,it probably is time for fuel lines and filter . btw have you checked muffler to see if it or screen is clogged?

[Mel M Kelly]

Put a new spark plug in also. It fixed the carb adjustment problem I thought I had in my old saw.

From Mel & Donnie in Bluebird Valley

[Auto Tech]

The Carb is a Walbro, Restrob has been walking me thru some of the area's where I have been and still am in the dark. I had a schematic of the carb breakdown and it did not show a metal disc covering a screen and when I can spare the saw for a day I will once again see about popping that metal disc and access the screen. As I said to Restrob she has no guts and needs constant tweaking when I am cutting wood. She has a new fuel filter in her tank and the hose is not collapsed it is in great condition. This happened suddenly when I was cutting sideways she suddenly starved and had no high jets so I rebuilt the car using a kit.After the rebuild it was better but high was no where like it was and she was never doggish restrob said it was most likely the screen which I had not accessed.

[e-mail] wrote:

[Auto Tech]

Hi Restrob, I popped the pull cord today and was reinstalling it and did what I usually would do is tie a knot on the end of the cord like i would on a tractor or hand mowers pull cord but on this the knot is in the way. Is there supposed to be like midrift pin on the end of the pull cord on the 1984 154 SE Huskavarna ?

Auto Tech wrote:

[restrorob]

Sorry so late checking back.....No no pin in this one just a knot, Mak sure you got the right size rope and pull the knot tight with two pair of pliers to make it small as possible.

As for the welch plug (cover plug you called it) you shouldn't need t remove it, If you can't see the screen it wont be under that plug. I will be on the bottom side of the carb. under the pump cover.

If you noticed what I typed in the picture I posted, The screen coul be on either the top or bottom of this carb.

One other thing you may want to check since you have the recoi assembly off is the crankshaft bearings. Do this by grabbing th flywheel and try rocking it up and down, If the bearings are worn it' possible the crank seals are leaking (sucking air) causing a lean an rich condition (as you saying continuous adjusting required)

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[Auto Tech]

Thanks for the reply Restrob. Boy I hope the bearings are not loose for that may take my saw where I do not wish to take it. To the trash can. I doubt she is worth the price of a complete overhaul for then the only part left will be the plastic casing.

restrorob wrote:

[Auto Tech]

Hi Restrob, By now you must think ""Oh what does he want now"" When you see me write you. I managed to get the pull start to work and got her started. Now I checked the crank for play while the recoil was off and no play. However I am going to fling this saw off a wall soon. I replaced that screen you told me about while the saw was apart for the pull starter and she started up running great however a few moments later she started to hesitate on high r,p,m engagement so I tinkered once again with the fuel settings and she is more responsive to fuel mixture tinkering and stalls much quicker BUT she is having so much trouble when I pull up on the trigger for high r,p,m's she dogs and I adjust and move mixture only say an 1/8 of a turn either way and one way she stalls almost instantly and the other she loads and stalls. Her idle mixtures are even more sensitive and she was never so sensitive. Any idea's any thoughts is appreciated.

Auto Tech wrote:

[restrorob]

OK, Have you replaced the spark plug since you have been adjusting th carb. so much ? Is it still white looking ? Do you have a in-lin spark tester ? Did you replace the carb. mount gasket ? Did you ge the gasket on right where the small hole aligned with the impulse hol in the cylinder ? Close both the low speed and hi speed adjustmen screws. Open the low speed one turn and leave it, Open the high speed

1/4 to 1 1/2 turns then start it up and try adjusting the high spee only at this point. Opening is richening closing is leaning, If you ge the high speed adjusted properly go back to the low speed and fine tun it. A lean low speed (Screwed in too far) with cause a bog on throttl up +------------------------------------------------------------------- +-------------------------------------------------------------------

[Auto Tech]

Hi Restrob, Originally yes I did replace those gaskets but not since. Plug still looks new. What about that third screw on the bottm under the high low mixture screws ? It is for idle but seems to directly affect the mixtures because after the overhaul she was racing and I lowered it and the mixtures went out of wack and needed a reset. What part does this play is it like the old Carter AFB carb where you had the big air bleed on the bottom between the mixtures ? Does that screw control a air bleed ? My car spark tester does not seem to work on this machine must be different in voltage than a car engines voltage. I was so furious day before last that I wanted to send it sailing into the nearest wall.

restrorob wrote:

[restrorob]

The idle adjustment screw only regulates the butterfly, Set the hi an low screws where I suggested and try starting it. If it idles too hig with the low speed adjuster opened at one turn leave that adjuste alone and only lower the idle screw.

If you still can't get it running properly have a friend snap a pictur as it hits the wall and post it here. Then go buy yourself a STIHL an be done with it !!

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[Auto Tech]

Ha ha ha ha ha ha ha ! I will do that and the way I feel right now I am in need of a saw that is better. I do have to give credit where credit is due and that the Husqvarna served me for years with out one glitch. I got this saw by doing work for someone on his vehicle and he could not pay for the work that was done so he gave me the saw as payment and that was some 10 years ago.

restrorob wrote:

[JD]

Sell it on eBay and get a STIHL JD