Stihl HP super 2 stroke oil

[Marc]

Anyone else running this oil? Supposedly this oil is better for Hedgecutters and 4-mix engines, due to less carbon deposits.

 

Only its been causing problems with my 200T, I have poor running issues i.e the engine will not pick up revs smoothly and a high idle. I used to run my saw on Stihls red 2 stroke oil with great results.

 

I've found it hard to tune with this oil 2 as its smokless which I used as a guide to how lean or rich the engine runs, not only that my exhaust is always dry with a small amount of black powder left behind.

Whereas before there used to be a small amount of oil and hardly any black deposits with the ordinary red stuff.

 

And to make matters worse I took out the spark plug to inspect it, and looked in to the piston chamber only to find lumps of black deposits floating round. My saw is only about 6 months old.

 

Anyone know what could cause the black deposits in my engine? there are no other signs of excesive carbon deposits in the ports etc?

 

 

I've now got my saw to run better, I needed to tune the low speed screw slightly richer. I still have more black stuff building up around the exhaust exit than usual.

 

Anyone else running HP super or used it

[treediver]

Ive used HP Super on all my saws n hedgecutters for the last 7 yrs or so and prior to that used HT plus bio which it replaced. The reason I moved from the red was du to the stinkin smoke and smell i hate mainly when hedgecutting. Plus it offers better lubrication and reduced wear which ive noticed especially on my HS 80 which has to be 'the' most abused hedgecutter in the uk and although the blades are beyond sharpening needing replacement, after 6yrs use the engine is still runs sweet.

[Andy Collins]

As I think I've posted elsewhere, I have now gone to a 4stroke Honda trimmer, as the fumes are a pain in the backside when working on thick hedge trims. As far as the fumes/smoke from your 200t, Ive never had much of a problem with that, from any saw. Are you sure your mix ratios are correct, as a starter, b4 you start twiddling screws and making adjustments.

[Marc]

Big A I never said my 200t smokes, I did say that I like to see a little smoke to know my saw isn't running to lean, although I know its not the best indicator.

 

With the HP super there is no smoke and after one run I noticed the casing was melted around the exhaust, which lead me to worry the saw was running lean and I may of caused damage. That and the fact it was running poorly on occasions.

 

One of the 200t's running on Stihl HP has burned out with heavy scoring around the exhaust port and its only around a year old.

 

 

I think i've sorted it now, I just had to tune the low speed a little richer (very small adjustment) and now it runs faultlessly.

 

It has just been affecting a couple of the 200ts some of which seem to run a little lean at factory settings???? None of the other machine have had problems.

 

 

What I really wanted to know is what could be the cause of the black deposits in the piston chamber as seen through the spark plug hole? Can't be carbon, almost looked like dirt getting in past the air filter, but so much after a run? I'll try to take a look in other saws

[treediver]

Its most likely carbon deposits forming on your piston head. When i strip my saws down the tops of the pistons and chamber around the plug have a rock hard coating of carbon some of which can flake off. If its not that it could be bits of residue from the exhaust getting into the chamber when the saws not running. Both of which you cant do much about. As for dirt getting in.. unless your using no filter theres 0% chance of getting dirt in the chamber.

[Marc]

Its curious allright, its deffinetly not carbon from the top of the chamber its not hard or flakey.

 

Looks more black crumbly and oily.

[Andy Collins]

Big A I never said my 200t smokes, I did say that I like to see a little smoke to know my saw isn't running to lean, although I know its not the best indicator.

Sorry Marc, I wasnt reading you quite right, but I have never used the output of smoke to gauge the tuning of my saws. Several years ago, all saws ran very smokily, the mix ratios were as strong as 16:1, 32:1, 40:1. Its only with the advent of the new "super" 2-stroke oils that we run 50:1. Having not used the HP oil, I have nothing to add at this point.

[Andy Collins]

Ok, talking in my local saw shop today, discussed the point Marc has brought up. Tuning a saw by ear is not always reliable, how keen is your hearing, can you differentiate 1000rpm either way, 500? Use a tacho to set em up. Using exhaust emmision is not to reliable as modern oils are so well refined, they just dont produce enough smoke, and if they are, have you found/created another problem? Again, use a tacho to set up. Modern 2-strokes are finely tuned pieces of kit with very little tolerance for the home mechanic to play with, and as they are what we rely on to earn our bread and butter...... well you decide.

As far as the deposits on the piston etc, they are most certainly carbon.

As far as oily liquid running from the exhaust, well its unburnt oil residue, not that I can say mine do that.

Take your kit to the people who know how to set it up properly.

[Steve Bullman]

ive always said that when people pick up a saw and claim they can tune it by ear....i wont let anyone anywhere near my say without a tacho

[Marc]

All good points, I can't tune a saw for s**t let alone by ear. And I don't always have the time to take them to a dealer and say sort it out please.

My saw was running bad I need it for work so I made a few very small adjustments, carefull only to adjust one thing at a time. Now it seems to run fine, but probably not to its optimum.

 

As for my understanding of 2 stroke tuning, i.e smoke and oil from exhuast it comes from a time when I used to run model cars.

A little smoke at full revs and some unburnt oil meant the engine was'nt running lean. And those little engines put out some power, 3.5cc, 1.5hp running upto 40,000 rpm, running on alcohol.

 

So my knowledge is probably not to relevent to higher cc 2 stroke.

 

Tuning by ear is impossible, only most of my local dealers probably could'nt tune it any better. Besides a saw can change when at work due to weather or maybe you will use different fuel from tim to time like me etc. So I think a tacho looks like a worthwhile invesment.

 

 

As for the black stuff in the piston chamber, having split open an old exhaust I'm begining to think thats wear it came from, its certainly not from the chsmber itself.

I reckon I blew it in there when I was cleaning my saw with an air line.