Ive got a 038 that i´m rebuilding and it needed a new cylinder. I thought it was a 038 av so i got a 50mm cylinder for it but the bolt pattern doesn´t fit. So it might be a magnum which has a 52mm with a bigger bolt pattern. But before i buy another cylinder, does anyone know the bolt pattern for the 52mm so i can measure it first? ( dont have the old cylinder so i can´t measure that )
stihl 038
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HArborist2
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I did a little research, and here’s what I found, but it’s definitely worth double-checking:
the Stihl 038 AV has a 50 mm bore and a smaller bolt pattern, while the 038 Magnum comes with a 52 mm bore and wider bolt spacing.
Bolt pattern (center-to-center):
038 AV (50 mm): roughly 68–70 mm
038 Magnum (52 mm): approximately 74–76 mm
Before you order, be sure to measure the stud spacing on your crankcase. You can also check the model plate on the starter or clutch cover if it says “038 Magnum,” you’ll need the 52 mm cylinder with the wider bolt pattern.
the Stihl 038 AV has a 50 mm bore and a smaller bolt pattern, while the 038 Magnum comes with a 52 mm bore and wider bolt spacing.
Bolt pattern (center-to-center):
038 AV (50 mm): roughly 68–70 mm
038 Magnum (52 mm): approximately 74–76 mm
Before you order, be sure to measure the stud spacing on your crankcase. You can also check the model plate on the starter or clutch cover if it says “038 Magnum,” you’ll need the 52 mm cylinder with the wider bolt pattern.
thank you for the help
HArborist2
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Hope you’ve got everything sorted now.
Tldrggr
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Hello, Sir. I've been reading your posts since I first joined this forum, and I think you are one of the most qualified sources on old Stihl aluminum. So, I'm asking a related question about my own 038. I recognize the 038 had more variants than any other Stihl model, but would like to know which one I have. I got it from a pawn shop back in the late 80's, and it had already been used pretty hard... perhaps by a short wood hauler, as those still existed in the South back then. My tags/stickers have been missing for many, many, years. I know it's at least an AV, (likely AVE), but would like to find out more, without tearing it down to measure the jug or piston. I don't see a serial number tag visible from the outside, is it located behind the recoil or clutch cover? Pretty sure I've seen it somewhere before as I have kept it going since I got it in '88. It's still my favorite for bucking firewood with a nice bow bar. If you can, please let me know how I might determine the sub-model. Thank you, sir!
Stihls... 038, MS 250, & two 009s
Two Poulan 306 As (one just became a parts donor)
birdog
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I have a 038 Farm Boss so I'll jump in with what I know which isn't much.
On my 038 the serial number is on the clutch side right next to the muffler. I tried running my serial number through two local Stihl dealers and I was told the saw is too old to show up in their online database.
On my 038 the serial number is on the clutch side right next to the muffler. I tried running my serial number through two local Stihl dealers and I was told the saw is too old to show up in their online database.
Tldrggr
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Thank you for the info. When I get a chance, I'll take the clutch cover off of mine, and clean it up a bit hoping to find the serial plate.
See above.
Measure the piston. If not disassembled, go from inside edge of exhaust port to intake side of cylinder with a slide caliper. Doesn't need to be a great caliper. Those plastic harbor freight ones will work just fine
Not necessarily the smartest one on here.Just kinda like the commercial "We know alot, because we've seen alot."
Same as many repair people you will meet.
Measure the piston. If not disassembled, go from inside edge of exhaust port to intake side of cylinder with a slide caliper. Doesn't need to be a great caliper. Those plastic harbor freight ones will work just fine
Not necessarily the smartest one on here.Just kinda like the commercial "We know alot, because we've seen alot."
Same as many repair people you will meet.
Tldrggr
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Thank you, Sir! I queried "Grok" about it today, and (according to him) the serial number indicates it's a Brazilian saw. They all were supposedly "AV" and with the adjustable oiler, but no Quickstop, "he" surmised it was one of the Super or Super Pro models (66.8cc). I may get around to pulling the muffler someday... but regardless of what it is, this old saw sure does run good, fast and LOUD!
Tough thing to figure as I never cared about country of origin. Just what part fit on the Fiche. (Yup, that is what we were using then.) Stihl did not even say much about it. Usually said it on the tag.
One thing I did notice-the coils tended to have a red switch wire on them.. My or may not still be there as they failed more than others.
More info on the saw history sites than we had.
I am more a diagnosis and repair tech. I leave all the other stuff to collectors and those with more time to research.
Spring has sprung. Trimmers and brush cutters up the wazoo. Can't get carbs fast enough.
One thing I did notice-the coils tended to have a red switch wire on them.. My or may not still be there as they failed more than others.
More info on the saw history sites than we had.
I am more a diagnosis and repair tech. I leave all the other stuff to collectors and those with more time to research.
Spring has sprung. Trimmers and brush cutters up the wazoo. Can't get carbs fast enough.
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