Fog1965
ArboristSite Lurker
Thanks to the EPA and a less than honest dealer, I now get to rebuild my MS290. But, I have a few questions about these engines. My background in 2 cycles is over 30 years of high performance racing engines. They operate at higher rpms - 28,000-29,000 compared to the 12,000-14,000 of my 290. They also run on nitromethene, methonal, and oil and not gasoline/oil and produce about 32 hp/cubic inch instead of the 1.x hp/ci of my 290. Basically the same thing as a chainsaw engine only different. But the construction of the "case" is not what I am used to.
In looking at the IPL and service manual, I have a few questions which I am sure a number of people have already come across or know. From looking through the forum, I doubt that there is anything that someone here has not tried or done.
The lean EPA settings combined with the "Intelli-carb" and ethanol in the gas killed the piston cylinder assembly, so I needed a new jug and piston. Doing google searches I found a new long block for an MS290. Price looked good at $160, cheaper than a new piston/cylinder from a Stihl dealer. I just got it in the mail today, but have some questions. It has both Stihl and Mahle on the cylider. Also the part number does not match that of an MS290 or 029. It has 1127-029, while the IPL has 1127-20-1213 or 1216. This jug also has 46ZD11 on it, which I could not find. The case pan also has 1127-021-2560 A while the IPL has 1127-021-2500, so I don't know if it is a later version or not. The finish on the cylinder is duller than what I can see on mine right now. I have not taken my saw apart yet. Basiclly I am not sure what this part is, if it is really a new MS290 engine or something else - all I really know is it is all the parts are new (cylinder, piston, pan, crank, rod, bearings and seals). I plan on rebuilding the engine that is currently in the saw, maybe putting a 390 piston/cylinder on it or getting the dead one bored .120 and replated, when I get some more money. In racing you always had two of everything, except engines - I took 6 with me to a race.
The pan does not contact the cylinder assembly, there is a gap of around 1/32". I cannot push the two parts together by hand and don't want to force something. Are they designed this way to create a "crush" on the bearings to hold them in place when the bolts are tightened down. There was no mention of this in the service manual.
I plan on adjusting the carb from the factory settings to what it should be. My race engines were always set a slight bit rich, so I intend to do the same on my saw. I would also like to eliminate the "Intelli-carb" leaning out the mixture. I would just as soon have the engine go richer instead of burning down to tell me the filter needs cleaning. If there is a better carb, or some recommendation for changes to this one - I am open to that.
And lastly, my plans are to dump the Stihl oil - since I have no idea of its specs and go to Klotz KL200. That is the same oil I used in my race engines that take a lot more abuse than my chainsaw. Any experience on that oil in a chainsaw would be welcome as well. I plan on running 5% (19:1) since the ethanol can be as much as 15% in the Houston area now.
Any information will be welcome.
Thanks in advance,
Fog Tanner
In looking at the IPL and service manual, I have a few questions which I am sure a number of people have already come across or know. From looking through the forum, I doubt that there is anything that someone here has not tried or done.
The lean EPA settings combined with the "Intelli-carb" and ethanol in the gas killed the piston cylinder assembly, so I needed a new jug and piston. Doing google searches I found a new long block for an MS290. Price looked good at $160, cheaper than a new piston/cylinder from a Stihl dealer. I just got it in the mail today, but have some questions. It has both Stihl and Mahle on the cylider. Also the part number does not match that of an MS290 or 029. It has 1127-029, while the IPL has 1127-20-1213 or 1216. This jug also has 46ZD11 on it, which I could not find. The case pan also has 1127-021-2560 A while the IPL has 1127-021-2500, so I don't know if it is a later version or not. The finish on the cylinder is duller than what I can see on mine right now. I have not taken my saw apart yet. Basiclly I am not sure what this part is, if it is really a new MS290 engine or something else - all I really know is it is all the parts are new (cylinder, piston, pan, crank, rod, bearings and seals). I plan on rebuilding the engine that is currently in the saw, maybe putting a 390 piston/cylinder on it or getting the dead one bored .120 and replated, when I get some more money. In racing you always had two of everything, except engines - I took 6 with me to a race.
The pan does not contact the cylinder assembly, there is a gap of around 1/32". I cannot push the two parts together by hand and don't want to force something. Are they designed this way to create a "crush" on the bearings to hold them in place when the bolts are tightened down. There was no mention of this in the service manual.
I plan on adjusting the carb from the factory settings to what it should be. My race engines were always set a slight bit rich, so I intend to do the same on my saw. I would also like to eliminate the "Intelli-carb" leaning out the mixture. I would just as soon have the engine go richer instead of burning down to tell me the filter needs cleaning. If there is a better carb, or some recommendation for changes to this one - I am open to that.
And lastly, my plans are to dump the Stihl oil - since I have no idea of its specs and go to Klotz KL200. That is the same oil I used in my race engines that take a lot more abuse than my chainsaw. Any experience on that oil in a chainsaw would be welcome as well. I plan on running 5% (19:1) since the ethanol can be as much as 15% in the Houston area now.
Any information will be welcome.
Thanks in advance,
Fog Tanner