stihl 051

[djmercer1]

ive been lurking for awhile but never posted, but now i need help:

i have a stihl 051 that has been in regular service and ran normally only 2 weeks ago.

tried to start my saw this morning and she floods after 3-5 strokes of the starter rope, while flooding shes tries real hard to start. im using reasonably fresh gas(2-3 months), but the fuel is a tad rich(~32-1). compression is about 160psi cold, plug has been cleaned and gap checked, air filter is servicable but dirty, seem to be getting good spark.

any suggestions?

ps:
my other saw is a poulan pro(18", 42cc), but i have some timberjack work this week and want a real saw :help:

 

[Lakeside53]

Rebuild your carb... and pressure test it afterwards. The inlet needle seats wear on these old HS carbs.

 

[djmercer1]

ok, i havent touched the inlet needle yet(no access to rebuild kit yet), but with some foul language and patience i got her too run. i pulled the carb, removed the adjuster screws for inspection, checked the diaphram and tore the saw down to the motor for cleaning. put her back together and she runs, albeit not well due to carb being out of adjustment.

is correct procedure for this saw to start with both high and low adjust about 1.25 turns out from seated?

 

[Lakeside53]

1 turn on the H (and leave it there - the govenor in the carb will take over), and the L is about 1.25, then adjust for a good idle.

If your carb govenor messes up, it can flood the saw. Don't just defeat it, it's there for a reason.

 

[martrix]

Listen to the man.

My service manual for the 051 says exactly that. From seated position, 1 turn out for H, and 1 & 1/4 for L.

Can we see a pic of your beastie? I'm rebuilding mine at the moment and I have withdrawals.

 

[djmercer1]

sure, ill followup with pics in the next day or so. maybe if i get the issues fixed i give some video of her handling the 18" red spruce and 14" yellow birch from my upcoming job.:lifter:

the saw, while used, has been well maintained an is destined for an alaskan mill, we dont get enough big timber in nl to justify it as a carry saw. i have a 24" bar for 'carry work' and plan on a seperate 36"-42" bar for the mill. as for the mill comments and suggestions are welcome wrt bar/chain combos.

another issue has just come up with the saw----my saw doesnt seem to be feeding oil to the 'bar feed slot'. a few weeks ago i replaced the oring(and cclip as i broke it during removal) on the bar oil pump shaft(due to bar oil geting into the crank). all seemed ok with shaft but now she doesnt seem to be producing bar oil through the slot to feed the bar.

i must say that my trials today have been without the bar/chain as i broke the old chain recently. she now runs after carb adjustment, albeit rich to the point of producing fuel through the muffler(likely due to the rich condition and difficult starting in my orginal troubles, now fixed as she starts on 3-4 pull, but still only producing so-so power). any ideas?

as for using a tach for adjusting(not yet tried), i have one for automotive use. my tach requires as 12v source(normally from battery of auto). can i simply put the tach on the saw(with clamp around the spark plug wire) and use an external 12v source(are there any grounding issues to worry about?). what rpm should i try for at idle(im thinking 2000-3000??? maybe??).

maybe better for seperate thread, but im also looking at a mac timberbear for my brother(its on consignment at my saw guys shop). the saw seems to be in good shape and handles 10" birch easily. the asking price is $150cad. commments please?

also matrix; any chance i could get a copy of your service manual for the saw. i have the ipl, users manual but no service info?

btw, my job/profession is civil engineer in geotech centrifuge facility.

any other suggestions are welcome.:newbie:

thanks guys.

 

[martrix]

what is the ipl users manual?

 

[Lakeside53]

Oil pumps on the 051 can be a problem .. the gear wears - if it looks looks like a creset, it's toast. if it's straight, then it's o.k.... make sure the oil control lever is back beyond the half way point also..

Idle - 2300-2500 is normal.. but it really doesn't matter -just a good idle without the chain moving. If you can't get it then replace the clutch springs.

 

[djmercer1]

what is the ipl users manual?

'ipl and users manual'

sorry, i dont type very well...

 

[djmercer1]

pics of my 051av, #1

 

[djmercer1]

pics of my 051av, #2

videos of it in the cut will follow. im in the process of getting a new bar and chain. saw is going into an alaskan mill soon...

 

[martrix]

She's an oldie, but a goodie(hopefully)opcorn: . I am putting mine in a mill too.

I resized your pics.

 

[djmercer1]

She's an oldie, but a goodie(hopefully)opcorn: . I am putting mine in a mill too.

I resized your pics.

other than overall condition, what else do you check? the compression is strong, inspection of cylinder and piston seems ok, and the case doesnt seem to have been abused.

what else?

 

[martrix]

What was the compression?

Looks like a fair bit of oil coming out of the exhaust?

Have you had it running? If so, after check the air filter, is is really wet with fuel?

 

[djmercer1]

What was the compression?

Looks like a fair bit of oil coming out of the exhaust?

Have you had it running? If so, after check the air filter, is is really wet with fuel?

for the size of saw, she starts very easy---she will start on about 3-5 pullls---runs very rich though, and smokes like a bugger. i have a little difficulty keepig her running due to rich condition.

the exhaust, as noted, is wet with fuel. in my lame attempt at tuning i ran her very rich to the point of stall; i actually dumped unburnt fuel out of the muffler(some is also oil that was leaked from bad oring oil pump shaft). she also bleeds fuel into cylinder when tilted onto her side(i use a 3"high tub to tilt her onto her muffler side, she is tilted about 45deg).

the air filter is dry, but well worn--so it will be replaced.

her power is so-so. hit the throtle and she will bog from being too rich. otherwise she seems ok.

comments please?

thanks.

dave

 

[martrix]

Can you take a close-up pic of the clutch? Could be the angle playing a trick but one of the shoes look strange.

 

[djmercer1]

Can you take a close-up pic of the clutch? Could be the angle playing a trick but one of the shoes look strange.

im guessing your looking at the clutch shoe at 12:00 oclock position?

i notice it in the pic, but when i checked there is no bevel on the shoe itself.

you have a sharp eye...

dave

 

[andrethegiant70]

As Lake said, rebuild the carb.. easy and generally solves a lot of problems. It is also possible that your hard starting and smoking is bar oil. You probably need to address your o-ring problem.. it will be mighty difficult to get it to right right without doing that.

 

[djmercer1]

ok, im back for more help...

got the carb issues worked out and the saw now runs like a champ. shes fitted with a new chain and bar.

my current problem relates to the chain oiling system. i recently replaced a shaft oring to eliminate oil weeping(gushing) into the crank. i inspected the shaft and the mating worm(while inplace) and all seems well and true. the pins of the cover plate are intact. the hose from the pickup to the white teflon bracket in the tanks are clear. where else are the likely trouble spots?

also, should i be able to air into the pickup and out the oiler slot for the bar? if yes, i cannot, and where would the blockage likely be?

dave

 

[djmercer1]

ok, ive done some more investigation, heres what ive found:
1)port for bar oil from the oil feed slot to pump is clear
2)pickup tube in oil tank has a rather friction lose fit on white teflon fitting(possible point for air entry,instead of drawing oil up??)
3)looking in tank(limited view) shows that the white teflon fitting doesnt have much oil in it
4)i can blow air through from the oil pickup through oil feed slot for bar when i rotate the clutch sleeve by hand aligning the d-shaft
5)rotating the clutch sleeve shows that the oil pump drive worm rotates

any ideas?

dave