Stihl New 4 stroke using 2 stroke fuel mix

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Anyone have any thoughts on Stihl's new 4 stroke engines that use 2 stroke oil for lubrication? To me is seems like the worst of both worlds. You have all the hassel of 2 stroke premix and none of the advantages of a 4 stroke. I would think there would be less than perfect lubrication and you have lots of parts to wear out and ethanol in the gas to make sure they all rust together when stored for the winter. I have been a Stihl fan till now. I will have to see how the new engines last over time. I have a feeling this is a transitional engine design for Stihl.

Perry
 
Originally Posted By: perryg114
Anyone have any thoughts on Stihl's new 4 stroke engines that use 2 stroke oil for lubrication? To me is seems like the worst of both worlds. You have all the hassel of 2 stroke premix and none of the advantages of a 4 stroke. I would think there would be less than perfect lubrication and you have lots of parts to wear out and ethanol in the gas to make sure they all rust together when stored for the winter. I have been a Stihl fan till now. I will have to see how the new engines last over time. I have a feeling this is a transitional engine design for Stihl.

Perry


As a STIHL tech and owner I can assure you these are VERY good engines. I will however tell you that IMPROPER mix ratio's and poor quality OIL "WILL" cause you problems.

Use GOOD quality oil (I use STIHL Syn) and mix at the correct and recommended 50:1 ratio and you will have no issues.
Use c-rap oil and or incorrect mix ratio's and expect to drop a valve, or build up enough c-rap on the exhaust valve to loose compression and keep the engine from running.

These engines make great torque, have plenty of RPMs and run really well, however they do require you do your part.

In the last few years I wouldn't even be able to guess how many broken valves, dropped valve guides, and fugged up valve seats I've seen.. I can tell you that the majority of these have been caused by the operator though and not and issue with the engines themselves. Drop a valve and you "MAY" get lucky and not trash the valve seat but the again you may not? Don't run good oil, or the correct ration combined with low RPMs and OR excessive string length and you will be paying for a valve job. Make sure you also keep the valves adjusted properly and you will be GTG..

I've had my 4-Mix Kombi for several years now and living in Florida it See's a LOT of use.. I run the string trimmer, hedge trimmer, edger, and chain saw attachments regularly and ALL of them work great..

Edit to add:
BTW, these engines are considered Hybrids and actually have the best of BOTH 2 & 4-stroke features.
 
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Originally Posted By: Hallmark
I'll pass...thanks!


Not that an explanation is needed as your clearly entitled to your opinion but I would be interested in why you feel that way? Have you had bad experiences with these engines?

This is NOT a transitional motor and they work very well in certain applications. I don't think we will see them in STIHL chain saws, or cut-off saws but for back pack blowers, string trimmers, edgers, and the KOMBI units they work great.
 
Originally Posted By: Hallmark
I'll pass...thanks!
He's probly thinking like I am. Whats the point of a 4 stroke if your still mixing gas and oil? The reason for looking into a 4 stroke is to get away from mixing gas and oil.

I'm looking into the Propane fueled stuff but it's hard to find here. With Propane you don't have to worry about fuel gumming up the carb.
 
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Originally Posted By: Hallmark
I'll pass...thanks!


You're being short sighted, these are great engines and work well in all applications. The OP called them "new", lol, they aren't new at all as they've been available for close to ten years at this point. They really are the best of both worlds.
 
Originally Posted By: Chris142
Originally Posted By: Hallmark
I'll pass...thanks!
He's probly thinking like I am. Whats the point of a 4 stroke if your still mixing gas and oil? The reason for looking into a 4 stroke is to get away from mixing gas and oil.


Advantages of the Stihl 4-mix over a two stroke-

1) Produces MUCH less pollution, I have heard figures of 90% less hydrocarbons.
2) The power band is more usable, it doesn't fluctuate like a two stroke.
3) Less vibration.
4) Much quieter.
5) Built in compression release, very easy to start.
6) Uses less gas than a comparible two stroke.

Advantages of the Stihl 4-mix over other brands that use a 4 stroke motor-

1) No wet sump full of oil to pack around, that means it's lighter.
2) No worrying about running the crankcase out of oil.
3) No worryiong about tipping the engine on it's side to edge with.
4) Just have one can of gas with 2-cycle oil in it that runs everything, no way to grab the straight gas and have an accident.

As far as storage over the Winter, I think that's going to be a great selling point for buying a quart of the Stihl Moto-mix. With no alcohol and some very good stabilizers, this stuff will be ideal for the "last run" in Oct/Nov so the Moto-mix will be the only thing left in the carb until Spring.
 
Originally Posted By: Chris142
Originally Posted By: Hallmark
I'll pass...thanks!
He's probly thinking like I am. Whats the point of a 4 stroke if your still mixing gas and oil? The reason for looking into a 4 stroke is to get away from mixing gas and oil.

I'm looking into the Propane fueled stuff but it's hard to find here. With Propane you don't have to worry about fuel gumming up the carb.


The advantages are numerous, one being NO crankcase. These engines are VERY efficient and powerful, the Mix thing is no prob at all and every pc of true 4-Stroke handheld stuff I've ever worked on (except Honda)is/was junk....
These units make 4-Stroke Torque but are much lighter, they run very close to 2-stroke rpms but run more efficiently with less emissions..

BTW, propane is much less efficient a fuel..
 
Originally Posted By: hate2work
Originally Posted By: Chris142
Originally Posted By: Hallmark
I'll pass...thanks!
He's probly thinking like I am. Whats the point of a 4 stroke if your still mixing gas and oil? The reason for looking into a 4 stroke is to get away from mixing gas and oil.


Advantages of the Stihl 4-mix over a two stroke-

1) Produces MUCH less pollution, I have heard figures of 90% less hydrocarbons.
2) The power band is more usable, it doesn't fluctuate like a two stroke.
3) Less vibration.
4) Much quieter.
5) Built in compression release, very easy to start.
6) Uses less gas than a comparible two stroke.

Advantages of the Stihl 4-mix over other brands that use a 4 stroke motor-

1) No wet sump full of oil to pack around, that means it's lighter.
2) No worrying about running the crankcase out of oil.
3) No worryiong about tipping the engine on it's side to edge with.
4) Just have one can of gas with 2-cycle oil in it that runs everything, no way to grab the straight gas and have an accident.

As far as storage over the Winter, I think that's going to be a great selling point for buying a quart of the Stihl Moto-mix. With no alcohol and some very good stabilizers, this stuff will be ideal for the "last run" in Oct/Nov so the Moto-mix will be the only thing left in the carb until Spring.


Well said..
wink.gif
 
FNFAL308 , being a STIHL mechanic and owner what is your thought on TRUFUEL being run in these hybrid motors? I have used TRUFUEL with alot of success recently and wanted your opinion of this premix gas/oil in these STIHL motors. I like that it uses zero ethanol and a syn 2 stroke oil in the mix , thoughts?
 
Originally Posted By: Thax
FNFAL308 , being a STIHL mechanic and owner what is your thought on TRUFUEL being run in these hybrid motors? I have used TRUFUEL with alot of success recently and wanted your opinion of this premix gas/oil in these STIHL motors. I like that it uses zero ethanol and a syn 2 stroke oil in the mix , thoughts?


Bud I'd love to give you some good info but to be honest we just haven't sold enough of the Product for me to have any data at all. We do carry it and have for a few months but it's not been a big seller "yet"? IMHO the product "should" be a good option for the Homeowner and I have seen/heard nothing so far that would cause me any concern..

Much of our BIZ is Commercial guy's and I suspect they will continue to mix their own fuel simply because of the quantity of fuel they need/use.

I'll talk to the Shop owner today and se if he has had any feedback and will be sure to post up here anything worth while..
 
I own several of the stihl 4-mix engines, love them, no smoke or stink, sips fuel and has tons of power!

If anyone thinks they are the worst of both worlds, think again! Ive used straight two strokes, four strokes, and propane trimmers. none match up to the 4-mix.
 
Originally Posted By: Thax
FNFAL308 , being a STIHL mechanic and owner what is your thought on TRUFUEL being run in these hybrid motors? I have used TRUFUEL with alot of success recently and wanted your opinion of this premix gas/oil in these STIHL motors. I like that it uses zero ethanol and a syn 2 stroke oil in the mix , thoughts?


I have not tried the TRUFUEL product, but I am using the Stihl MotoMix and I really like it. You can tell from the odor it's not regular gasoline in there. I use it in my Stihl blower and hedge trimmer and my Echo trimmer.
 
Originally Posted By: Thax
FNFAL308 , being a STIHL mechanic and owner what is your thought on TRUFUEL being run in these hybrid motors? I have used TRUFUEL with alot of success recently and wanted your opinion of this premix gas/oil in these STIHL motors. I like that it uses zero ethanol and a syn 2 stroke oil in the mix , thoughts?


Stihl has their own product out called Motomix, that's the ticket, really makes these things hum. Plus I think it's going to be available in gallons soon. And it smells great too lol

http://www.stihl.com/isapi/default.asp?c...off/default.htm
 
Originally Posted By: hate2work
Originally Posted By: Thax
FNFAL308 , being a STIHL mechanic and owner what is your thought on TRUFUEL being run in these hybrid motors? I have used TRUFUEL with alot of success recently and wanted your opinion of this premix gas/oil in these STIHL motors. I like that it uses zero ethanol and a syn 2 stroke oil in the mix , thoughts?


Stihl has their own product out called Motomix, that's the ticket, really makes these things hum. Plus I think it's going to be available in gallons soon. And it smells great too lol


The fact that it burns so clean should make it ideal for the 4-Mix engines. Might make less work for us though..
wink.gif
 
Originally Posted By: Blaze
How often do you have to adjust the valves and how difficult is the job for a typical user?

Very easy.
1. order the special feeler gauge #4180-893-6400 and a new valve cover gasket #4180-029 0500
2. remove the three t27s that hold the orange engine cover in place.
2. remove the sparkplug, and the t27 screw that holds the valve cover on.
3. set the piston to tdc of the compression stroke.(both rockers will be a little loose at this point.
4. using an 8mm wrench tighten the self locking nuts atop the rocker arms while measuring the lash with your new feeler gauge until the lach is corrected.
5. when done pull the rope a few times and recheck the lash, adjust as needed.
6.replace the vc gasket, and vc cover. new plug in.
7.Check the throttle cable at this point to be sure it's opening the carb all the way, adj if needed.
8.install the orange cover and yer off.

The decompression lobe on the cam will now also be back in spec and the rope should pull effortlessly.

The decarb service should be done at this time as well.

Oh yea it should be done about every 125hrs, but will all depend on the way the tool is being used.
clogged air filter, bad adjustment on the throttle cable, poor fuel, poor oil, or oil mix, low rpm use, trim line too long(leading to low rmp use), or short tripping(if you will) will all lead to a shorter interval.

If nothing is ever done wrong they can go much longer than 125hrs.
 
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How much are you guys getting the Stihl MotoMix fuel for? Interesting idea for a trimmer that uses a gallon of fuel or less a year at my place. The ethanol 10% blend around here gums up carburetors.
 
I buy it from my local dealer for $7.99 per can. It is expensive, but for a low use item that spends most of its time setting, it's a great product. It's good for two years and it really does make the equipment run better. It's not just regular old gasoline, the smell alone will tell you that.
 
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