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- Thread starter parrisw
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parrisw
Tree Freak
Ya, don't pay any attention to my numbers when doing your saw. Figure it all out based on your saw.
Mastermind
Work Saw Specialist
Running great as always Will. 
parrisw
Tree Freak
Running great as always Will.
Thanks!
parrisw
Tree Freak
Your welcome! I certainly love these series of Huskies!! Nothing else I've run comes close.
Looks like a good runner!! In the first vid the chain seemed a bit grabby. After that the chain cut fine untill that last cut, been there done that lol.
parrisw
Tree Freak
Looks like a good runner!! In the first vid the chain seemed a bit grabby. After that the chain cut fine untill that last cut, been there done that lol.
LOL yup. Like I said wasn't too happy with the chains. The last two vids it was a different bar and chain, sorry forgot to mention that, it was 24" oregon full chisel.
Stumpys Customs
Stumpbroke
Gotta love the 372 oem or aftermarket, they just rock
Great job on the saw Will.
Great job on the saw Will.
parrisw
Tree Freak
Gotta love the 372 oem or aftermarket, they just rock
Great job on the saw Will.
Thanks Stumpy! The 372 is a all time legend! Sad that its gone, out of the lineup.
Terry Syd
Addicted to ArboristSite
I got a bit antsy/bored and decided to make up some clay and check the area of the transfer ports on the BB kit. I did a bit of rounding off on some of the figures, but all in all the BB kit does have enough transfer port area to flow if the ports are completely open, that is, if the top of the piston is cut down to the bottom of the port.
The figures I got were for around .0066 (or a little more) at 10,500 rpm.
The carburetor size leaves me cold - only 17mm. I think I recall Al boring out the carb, or putting a 385 carb on that was bigger. Anybody have any ideas about swapping carbs on the 372?
The figures I got were for around .0066 (or a little more) at 10,500 rpm.
The carburetor size leaves me cold - only 17mm. I think I recall Al boring out the carb, or putting a 385 carb on that was bigger. Anybody have any ideas about swapping carbs on the 372?
parrisw
Tree Freak
Don't know about carb swaps. Been wanting to bore one out though.
Boleclimber
ArboristSite Guru
I ran a 385 carb on an alcohol saw I built. The bolt holes line up but the 385 carb is slightly longer (needed longer bolts) and it sits at an angle. I attempted to use a 385 intake boot, to level the carb, but the intake mount diameter is smaller on a 372 than 385.
I never attempted to mount a air filter system using the 385 carb. A filter, especially the HD, may hit the top cover towards the rear handle.
Terry Syd
Addicted to ArboristSite
Thanks guys, I found the thread where Al bored out the carb. He opened it up 1.1mm at the venturi and didn't have any problems. - That's only another 6% larger than stock 365 carb, but it helps narrow the gap with the 18% increase in displacement. Too bad about the hassle with the 385 carb, it would have closed the gap a bit more.
Terry Syd
Addicted to ArboristSite
Crikey, I misread Al's thread - he opened the carb up from a 16.7mm venturi to a 17.5mm venturi - that is a tad less than 5% increase in area. Too bad about the tilt on the 385 series carb, that could go to 19mm.
I may not need to bore the carb, I can order a 17.5mm carb from M&D. Here's a link to their listings for the carbs - http://www.m-and-d.com/pdfs/zama/C3A_M_PARTS_LIST.pdf
Perhaps the throttle valve is a bit bigger, which may allow a bit more boring of the venturi. I'll have to talk to the tech at Zama to get the throttle bore specs on the 17.5mm carb. If I do purchase a carb, this time I will order a complete selection of metering springs in order to help me set the POP. I should have done that when I got the bigger carb for the 450.
I may not need to bore the carb, I can order a 17.5mm carb from M&D. Here's a link to their listings for the carbs - http://www.m-and-d.com/pdfs/zama/C3A_M_PARTS_LIST.pdf
Perhaps the throttle valve is a bit bigger, which may allow a bit more boring of the venturi. I'll have to talk to the tech at Zama to get the throttle bore specs on the 17.5mm carb. If I do purchase a carb, this time I will order a complete selection of metering springs in order to help me set the POP. I should have done that when I got the bigger carb for the 450.
AUSSIE1
Al.
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Your getting into very dangerous territory Terry. This class husky is very addictive!
Boring that carb wasn't without incident. It ####ed with my mind for weeks till I worked out the issue I was having with it. At home it ran like #### of a shovel. I'd take it out bush with approx another 3-400 metres above sea level and it would play up like you would believe! I eventually pressurised it under water and bingo! I'd popped through to one of the primary ports! Man does nail polish work well for sealing little carb sealing issues!
Here's the saw running still with issue's prior to find the problem.
<iframe width="560" height="315" src="http://www.youtube.com/embed/C2gqY5hZUGY" frameborder="0" allowfullscreen></iframe>
The carb sits on the shelf these days as I've been running a different kit on it lately.
I had difficulty finding an inlet manifold to match the increase in size. I was going to manufacture one but never got there. I was going to play with runner length to match inlet pulses but didn't get around to it. Maybe in the near future. I'm bidding on a lathe so that will renew the interest and apart from some cyl work, making some inlet pits and pieces may prove interesting.
Here's the saw running in a firewood environment (hardwood) with the carb fixed. nothing else done.
<iframe width="560" height="315" src="http://www.youtube.com/embed/zxkNrVgxVqY" frameborder="0" allowfullscreen></iframe>
Sorry Will, let er rip rip rip!
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AUSSIE1
Al.
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The 385/90 and 395 carbs run the same bore size as the 371/2 from memory with differences in the venturi of course amongst other things.
AUSSIE1
Al.
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You had to play with MUD to come to that conclusion Terry? :msp_w00t:
MCW
Somebody's talking crap here & it ain't the tree!
Mud dulls chains Al...
Terry Syd
Addicted to ArboristSite
No mud, I had to make up some clay out of flour, water and vegetable oil. I tried some children's Play Dough, but the stuff was too elastic. The clay I made up was a lot firmer, it would hold the shape of the port and was able to be removed without stretching. - After I finished with it, I gave it to the chickens and they thought it was Christmas.
I don't know what the bore size is on the 19mm Walbro WJ carbs (the series on the 385). If it is the same as the Zama C3M EL8 carb, then there may be room for some more work on the venturi.
The reason I'm looking at the carb options is that I would prefer a shorter intake duration with a bigger carb versus a smaller carb and a longer intake duration. I'm doing a bit of research before I start hacking away at the BB jug. I'd hate to find out later that there was a bigger carb for the engine.
Just to put this carb size issue in perspective, I'm running the equivalent of a 19mm carb on my 50cc 450, so with that background I'm not feeling all that comfortable with a 17-17.5mm carb on a 77cc engine.
I don't know what the bore size is on the 19mm Walbro WJ carbs (the series on the 385). If it is the same as the Zama C3M EL8 carb, then there may be room for some more work on the venturi.
The reason I'm looking at the carb options is that I would prefer a shorter intake duration with a bigger carb versus a smaller carb and a longer intake duration. I'm doing a bit of research before I start hacking away at the BB jug. I'd hate to find out later that there was a bigger carb for the engine.
Just to put this carb size issue in perspective, I'm running the equivalent of a 19mm carb on my 50cc 450, so with that background I'm not feeling all that comfortable with a 17-17.5mm carb on a 77cc engine.
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