McCulloch Chain Saws
- Thread starter Bruce Hopf
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Author was GASoline71
Mark
Author was GASoline71
Mark
Thank you sir! I did notice something after I rebuilt that carb - while I was trying to start it it seemed to be leaking gas from the underside of the carb because I couldn't see it but the carb area was collecting gas. I did use the fuel filter gasket from the kit rather than reusing the rubber gasket. Was that a mistake?
Update: apparently with that bronze fuel filter you cannot use the gasket that comes in the rebuild kits. Only way to prevent leaks is to reuse the rubber gasket in the carb. I found this out the hard way - lots of gas leaking out of carb.
Update: reused rubber gasket and gas leak was worse, puddled under saw after I shut it off. Lots of gas in carb compartment.
Is there a fuel line in the gas tank that could be collapsing and holding suction?
Is there a fuel line in the gas tank that could be collapsing and holding suction?
Finally got smart and put some dye in the fuel. It seems to be leaking/draining from where that metal fuel line enters the carb compartment. At least I know its not a carb issue. That fuel line nipple is tucked up in that corner so its hard to see if its leaking from the line or around the line.
This evening while I was documenting and celebrating the receipt of an NOS bar and chain from our good friend Mark, my daughter who is helping to work the tractor pull tonight at our county fair which opened this evening, texted and said three folks fell from the Ferris wheel near the top. Two air-lifted and third ground transported. I'm sure the injured and their families would appreciate your prayers.
Thanks, Ron
Thanks, Ron
Now with happier news:
Package from Mark. Great sturdy wrap job. Nice touch using yellow tape with black tape trim.
NOS Spike from my inventory.
SP 40 ready for testing at Brian's and my upcoming little 82cc shootout. I hope it runs as well as I remember my old PM 510 did. I measured 174 psi using my gauge that Brian believes may be reading 10# short. If my PM 510 was any where close to this then there is no wonder why I was always ripping the starter cover loose - which in the end is why I tossed it 35 years ago.
Ron
Package from Mark. Great sturdy wrap job. Nice touch using yellow tape with black tape trim.
NOS Spike from my inventory.
SP 40 ready for testing at Brian's and my upcoming little 82cc shootout. I hope it runs as well as I remember my old PM 510 did. I measured 174 psi using my gauge that Brian believes may be reading 10# short. If my PM 510 was any where close to this then there is no wonder why I was always ripping the starter cover loose - which in the end is why I tossed it 35 years ago.
Ron
The SP40/PM510 are not bad little saws, and certainly much easier to work on than your run of the mill Mini Mac since you can get at the carburetor without dismantling the whole thing.
Speaking of Mini Mac's, my neighbor across the street handed me another last night (MM25) that he said was leaking fuel...most of the time this turns out to be a crack in the fuel tank where it attaches to the bottom of the saw. Maybe I will finally get the tree work done that has been occupying all of my time the past two weeks and get back into the shop.
I did run my 7-10 extensively last Saturday and like that saw better every time I use it.
Mark
Speaking of Mini Mac's, my neighbor across the street handed me another last night (MM25) that he said was leaking fuel...most of the time this turns out to be a crack in the fuel tank where it attaches to the bottom of the saw. Maybe I will finally get the tree work done that has been occupying all of my time the past two weeks and get back into the shop.
I did run my 7-10 extensively last Saturday and like that saw better every time I use it.
Mark
Ron, I was walking into the fair just after the accident happened. I am praying for the girls that were hurt during this accident.
Thanks, Brian. The news reports that the 6 year old is still in critical condition.
Do you have time this weekend for the shootout?
Ron
Do you have time this weekend for the shootout?
Ron
Maybe Saturday
Bronco - you will find that there are a couple of tapped holes (8-32?) in the clutch, use a puller and pop the clutch/spider off then remove the key, then the drum will come off.
Alternative is to leave the nut just covering the end of the threads and give it a tap while holding the saw off the bench by the clutch, once the spider is off you still have to remove the key before the drum will come off.
Mark
Alternative is to leave the nut just covering the end of the threads and give it a tap while holding the saw off the bench by the clutch, once the spider is off you still have to remove the key before the drum will come off.
Mark
Brian, his son and I had our little 82cc shootout late this afternoon. The saws were: a can't tell from new Double Eagle 80; a PM 850 that Brian built for me that is fresh and has only been put through heat cycles by Brian; my go to PM 800 with old style muffler; and Brian stock PM800. We only use 24" bars which was not quite as planned but the 92 degree+ heat almost did me in after spending most of the day outside mowing and trimming bushes.
Neither of us claim any chain sharpening expertise so we used fresh full comp Stihl RS off the same roll. Brian tuned all of the saws "in the wood" before we started on a just over bar length red oak. Neither of us are cookie cutters as you will clearly see if Brian's video camera worked. If it did, we will post it later. Candidly, knowing that we were filming made me a little nervous until I just forgot about it. Our impressions are just that as neither of us cut consistently enough to make timing meaningful.
My camera's card is only good for about 4 minutes so the below is all I shot. The saw shown is a PM 850. Very impressive saw. The first cut was just squaring up the log; after that our procedure was I would cut one cookie then Brian would cut the next cookie then we would move on to the next saw.
I will let Brian speak for himself except to say I believe the almost new Double Eagle 80 was his favorite during the tuning process although with the different carb layout it was the more difficult than the others to tune.
PM 850 with 24" bar - red oak
Ron
Neither of us claim any chain sharpening expertise so we used fresh full comp Stihl RS off the same roll. Brian tuned all of the saws "in the wood" before we started on a just over bar length red oak. Neither of us are cookie cutters as you will clearly see if Brian's video camera worked. If it did, we will post it later. Candidly, knowing that we were filming made me a little nervous until I just forgot about it. Our impressions are just that as neither of us cut consistently enough to make timing meaningful.
My camera's card is only good for about 4 minutes so the below is all I shot. The saw shown is a PM 850. Very impressive saw. The first cut was just squaring up the log; after that our procedure was I would cut one cookie then Brian would cut the next cookie then we would move on to the next saw.
I will let Brian speak for himself except to say I believe the almost new Double Eagle 80 was his favorite during the tuning process although with the different carb layout it was the more difficult than the others to tune.
PM 850 with 24" bar - red oak
Ron
Okay add to the list things I cannot do: post a working video. I will try another approach later. Ron
As promised in another thread, we check the rpm's of each saw. Brian's tach is a photo cell so we measured off the clutch drum. Results were a little surprising to me given my impressions which I will get to later. Brian's 800 - almost 12,900. 850 - right at 12,500. My 800 - around 11,700 then Brian discovered that the decomp was loose; tighten it up and it jumped to 12,300. DE 80 - consistently 9,900 to 10,000. Brian leaned it some and it hit 11,300 but we put it back to where it was originally tuned.
In the cut, Bryan's 800 felt the strongest. The other three were pretty much the same despite my 800 having an 8 tooth sprocket. Given my impressions, I was a little surprised by the max rpm difference of the DE 80.
The 850 had noticeably more vibration. Brian attributed that to the NOS stiff as a board AV mounts. I didn't seem to notice the screwed together AV mounts on my 800 as I had previously. I tweaked them a little when I had it apart the other day while working on the oiler. I am not sure whether or not Brian felt any vibration difference in the 800's.
During the rpm testing, my 800 hands down put out more oil so hopefully it is finally fixed.
Now let me work on that video.
Ron
In the cut, Bryan's 800 felt the strongest. The other three were pretty much the same despite my 800 having an 8 tooth sprocket. Given my impressions, I was a little surprised by the max rpm difference of the DE 80.
The 850 had noticeably more vibration. Brian attributed that to the NOS stiff as a board AV mounts. I didn't seem to notice the screwed together AV mounts on my 800 as I had previously. I tweaked them a little when I had it apart the other day while working on the oiler. I am not sure whether or not Brian felt any vibration difference in the 800's.
During the rpm testing, my 800 hands down put out more oil so hopefully it is finally fixed.
Now let me work on that video.
Ron
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