Stihl 044 Oiler Mod

[MG porting]

It works. Just pay attention to your oil tank. Its possible to drain it before you run out of fuel

Oh yeah that's for sure they pump the oil out way good definitely need to stalk up on bar oil. Lol.

 

[Snowman56]

In order for the pump to flow more oil, I like to give the piston more stroke. To do this, find the lowest part of the ramp

View attachment 94400

and measure how far it is from the end

View attachment 94401

I've found .015-.020" more ramp to be sufficient. I do this with a cut-off wheel and a diamond burr to polish it

View attachment 94402

You'll also need to remove that same .015" from the corresponding area of the end of the control bolt where it's in the "max oil" position
View attachment 94403

Any chance you could clarify exactly where on the end of the control bolt this is. Sorry, I know I'm about 8 years late to the party but im getting ready to attempt this on a spare 440 oiler I just got. Thanks

 

[Sloughfoot]

Any chance you could clarify exactly where on the end of the control bolt this is. Sorry, I know I'm about 8 years late to the party but im getting ready to attempt this on a spare 440 oiler I just got. Thanks

What you're asking about may be in the top photo of post #4.

 

[SteveSr]

Time to dredge this thread up again! I finally have a need to put my 044 to work cutting some charity firewood and I need to get this pump modification done first as these trunks are now dry and will soak up oil like a sponge.


Here is the new control bolt as listed in the 2004 MS460 for t he Rescue Saw (H.O Oiler)



Here is the original control bolt on the left. HO control bolt on the right. The flats on the end of the bolts are orientated the same (down). Yes, they are different.

The first order of business was to measure the piston travel in both the min an max settings of the control bolt.

044 oil pump as found (unmodified pump piston)
Min travel - .014"
Max travel - .032"

Next I swapped out the control bolt only

044 oil pump ( H.O. control bolt & unmodified pump piston)
Min travel - .009"
Max travel - .031"

Interesting outcome... According to these measurements changing the control bolt only should have zero increase in oil output!

For those that saw an increase by taking the pump apart and changing out just the control bolt probably just ended up cleaning out some crud from the pump. I have seen this before on at least one 026/MS260. The pickup screen in the oil tank is coarse enough to let some sawdust and crud through it. Most of this will get flushed out to the bar but some will build up in the pump and eventually reduce piston travel and reduce oil output.

So the max travel with the original piston is about .032" (0.8mm) Sound familiar?

Guess what else measures .032"? If you measure the difference in the high and low points of the cam on the piston you get... .032"! So the cam on the piston ultimately limits the maximum piston travel.

So how does the control bolt fit in?


Here is the orientation of the control bolt at max flow with the unmodified pump piston. Note that both cams on the control bolt mesh with corresponding surfaces on the piston (circled in red).



Here is the HO control bolt and the unmodified piston. Note the air gap between the small cam on the HO control bolt and the stop on the piston. The only way to make these match up is to machine the ramp on the piston as others have done before.

I used a 3/16" round diamond hone in my dremel at the lowest speed and followed up with a flat #320 diamond hone. According to my measurements I took off about .015 max but it may not be perfectly flat as it should be. It looked like the surfaces mated well outside the pump.

So I reassembled the pump and did some final measurements:

044 oil pump (HO control bolt & modified pump piston)
Min travel - .009"
Max travel - .040" (1.0mm)

 

[huskihl]

Be careful on max oil setting or you will run out of oil before gas. I believe it’s been mentioned in here a few times that you can leave the gas down about an inch from the top when you fill up and you should be close

 

[huskihl]

@chipper1 does that so he can take a break sooner

 

[SteveSr]

Be careful on max oil setting or you will run out of oil before gas. I believe it’s been mentioned in here a few times that you can leave the gas down about an inch from the top when you fill up and you should be close

This mod with the new 1.0mm stroke shouldn't be any worse than the stock HO pump which I wouldn't think would be designed to allow run out of oil before gas.

I'll find out on Saturday if the weather cooperates.

 

[huskihl]

This mod with the new 1.0mm stroke shouldn't be any worse than the stock HO pump which I wouldn't think would be designed to allow run out of oil before gas.

I'll find out on Saturday if the weather cooperates.

There is no HO option for an 044/440. It’s the HO oiler parts from a 460/461, which have a considerably larger oil tank. It definitely has the potential to run dry, as I’ve done it. One reason I created the thread was to show people it could be done but also that they will run out of oil

 

[SteveSr]

There is no HO option for an 044/440. It’s the HO oiler parts from a 460/461, which have a considerably larger oil tank. It definitely has the potential to run dry, as I’ve done it. One reason I created the thread was to show people it could be done but also that they will run out of oil

Good catch! I'll be careful.

I did a little digging through my repair manuals for this series and found the following:

Oil tank Capacities
044 = 330ml
046 = 325ml
MS460 = ?

The MS460 repair manual that I have doesn't list the oil tank capacity. I also have an MS460 IPL that shows the "R" Rescue Saw but does NOT show the HO oil pump which is supposedly used on that variant. Perhaps the HO oil pump was added in later productions of the MS460R?

 

[chipper1]

@chipper1 does that so he can take a break sooner

I resemble that remark.
I've been know to fill them a little less at the end of a long day, or when I just need a break sooner for sure .

 

[Basher]

There is no HO option for an 044/440. It’s the HO oiler parts from a 460/461, which have a considerably larger oil tank. It definitely has the potential to run dry, as I’ve done it. One reason I created the thread was to show people it could be done but also that they will run out of oil

There is no HO option for an 044/440. It’s the HO oiler parts from a 460/461, which have a considerably larger oil tank. It definitely has the potential to run dry, as I’ve done it. One reason I created the thread was to show people it could be done but also that they will run out of oil

The fuel tank appears larger on the 046 and MS460 so that may make a difference on the fuel outlasting the oil supply

 

[huskihl]

The fuel tank appears larger on the 046 and MS460 so that may make a difference on the fuel outlasting the oil supply

Could be, not sure why. I know on an 044/046 hybrid, they will run out with about 1/8 tank of fuel left. I’m sure thinner bar oil would also affect that

 

[Basher]

Could be, not sure why. I know on an 044/046 hybrid, they will run out with about 1/8 tank of fuel left. I’m sure thinner bar oil would also affect that

I have never needed to check the tank capacity but when observing the fuel tank on a 046 orMS460 they project out to the left side about flush to the recoil cover while on a 044 the tank is recessed back more than a half inch,. When fitting a 046 tank to a 044 ,can be done and have done so the 044 airfilter cover would need some adjusting to fit it to the fuel tank.

 

[jacob j.]

The fuel tank appears larger on the 046 and MS460 so that may make a difference on the fuel outlasting the oil supply

The crankcase on the 046/460 is wider as well, since the crankshaft is wider. It may be that oil tank on the 046/460 is shorter but I can check that since I have a lot of loose 044/440 and 046/460 case halves in a box.

 

[farminkarman]

I just found some numbers stating 11.2 oz for the ms440 oil tank and 12.5oz for the ms460.

 

[jacob j.]

I just found some numbers stating 11.2 oz for the ms440 oil tank and 12.5oz for the ms460.

That sounds more accurate to me.

 

[MustangMike]

I just found some numbers stating 11.2 oz for the ms440 oil tank and 12.5oz for the ms460.

Fuel or oil?

 

[farminkarman]

Fuel or oil?

those were numbers for the oil tanks

 

[EFSM]

I resemble that remark.

Good old Curly, right?