What is the reason for the lines on the 7900 intake? I have not noticed this on other saws. Is it a casting mark or intentional? Thanks.
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7900 Intake Port
- Thread starter NPKenny
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Just casting lines. I've seen them in my Stihls.
cbr929rr
ArboristSite Member
would it benefit to sand the lines smooth, or just leave it alone? Mine is the same way.
If that's all you did, I'd say you wouldn't notice anything.
Slamm
Addicted to ArboristSite
If you could measure or feel the difference that would make, you are one sensitive individual.
So yes, absolutely, by all means sand it, also modd the muffler and port the exhaust while you're at it.
I think in this light, you will feel the difference.
My opinion,
Sam
So yes, absolutely, by all means sand it, also modd the muffler and port the exhaust while you're at it.
I think in this light, you will feel the difference.
My opinion,
Sam
That is exactly my sentiment after working those lines and getting familiar with the cylinder. If you add these lines to the thousands of other small casting flaws that I ended up touching up on the cylinder, all of the extra material on the Piston, all of the wasted space between the piston at TDC and the cylinder, you will most certainly notice a difference.
When I had asked that question originally, that was the first time I had been into a saw. I ended up doing very minor work to that saw, including cleaning up all of the casting flaws and tightening the squish. It runs like a dream. I've since been into a few more saws and noticed that they all have those type of marks.
When I had asked that question originally, that was the first time I had been into a saw. I ended up doing very minor work to that saw, including cleaning up all of the casting flaws and tightening the squish. It runs like a dream. I've since been into a few more saws and noticed that they all have those type of marks.
cbr929rr
ArboristSite Member
I have removed the casting edges on the base transfers and cleaned up a little junk with a file and have done a muffler mod. Now I'm just waiting for a long T-27 wiah tool from baileys. I don't trust the stock tool. Don't want to bring it to a machine shop with stripped heads on the bolts. I am running a base gasket so I will probably leave the squish alone. This is my first time in a saw. What other things should I do. Do you have any pics?
