Wanting to tune my own saws...

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Elaine Landscapes

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Hi gang.

I started a landscaping company last year and have two girls and myself running things. When younger I worked at a ski hill, instructing in the winter and helped cutting new runs and general maintenance in the off seasons. I received a chainsaw course back then and have always enjoyed using a saw. Anytime friends are cutting firewood or dropping a tree I am the first one there. Anyway, my question(s) are:

I own two newer saws and have been doing all my own maintenance on them. After speaking to a few friends and reading threads here on the site, I would like to remove the limiter caps from both my 461 Stihl and my 490 Echo. The one thing that confuses me is due to conflicting reports about people who have removed the limiter caps. Some people say to pop them out, trim off the tabs and replace them. Others say to simply remove them. The people saying to replace them argue that it prevents the adjustment screws from backing out. I don’t see why the limiter caps would prevent the screws from turning. Mechanically there doesn’t seem to be anything that would stop the adjustment screws from turning if the limiter caps are removed. Am I missing something?

I watched a bunch of videos and have replaced the 461 muffler cover with a dual port cover and have conservatively opened up the muffler exit port on the 490. I am just waiting for a tach to arrive via Amazon before retuning the saws.

Thank you.
 
The mix needles should have springs to keep in adjustment with or without limiters the limiter was a device to satisfy the EPA "bods"either refit or removal will work fine some folk refit as it looks less "messed with .I find I use the 2 lumps either side my head as the #1 tuning tools very rarely use a tach
 
I agree with Little Al, the springs will keep the adjustment screws from moving. IF they do move then it is most likely the threads have been stripped within the carburetor. Limiter caps are there to keep the owners from leaning out the saws and destroying them. Personally I leave them in place as there is plenty of adjustment to compensate for elevation/temp/humidity/etc if the saw is kept in a stock or mostly stock configuration. A tach is on my wish list, but not a high priority. If the tach is only for use on a saw, then it is a toy and the ear is plenty good enough to tune the saw.
 
I pulled mine out and trimmed off the little tabs that prevent the caps from turning. I have half my echos with the caps put back in and have where I left the caps out. I haven't had a situation where the screws moved on their own.

I also found I have an easier time getting the adjustment screwdriver in and keeping it in when the caps where put back in.
 
You need the Stihl to 4 stroke when not in wood at wide open throttle regardless of what the tach reads

Even though I know what four stroking sounds like, my ears probably need some training to feel confident in not having it rev too high. I kinda thought that I would just set it (unloaded) a bit below the suggested 13,500 rpm.

You want it to four stroke wide open unloaded and then wind up clean when in the cut, right?

Do I run any risk in blowing up a saw if I have the high set to just below the max rpms? Right now I do have the low mixture screw set (screwed clockwise) between where it begins to stumble and (counterclockwise) where it wants to stall. So I have it in the middle there and then tweaked it counterclockwise just a bit (which would richen it up a tad, right?)

Sorry for all the questions - I tend to overthink things, but I would rather be safe than sorry...
 
Limiter caps are there to keep the owners from leaning out the saws and destroying them.



A tach is on my wish list, but not a high priority. If the tach is only for use on a saw, then it is a toy and the ear is plenty good enough to tune the saw.


I disagree with a couple things. Limiter tabs are meant to make the saws run very lean, often on the edge of self destruction. The tabs stop the saws from being richened up , not leaned out too much.

2nd. Saws that have rev limited coil can sound like 4 stroking when the bounce off the rev limiter. A tach will show this since you won't get a reading when this happens.

I cut a lot in the Winter, when it starts getting real cold the saws run leaner and you have to watch them. When they get a "buzzy" sound I get the tach out and re tune to a safer 12,800 - 13,000 RPM.
 
So fwiw, I received a tach via Amazon yesterday. I rechecked my tuning on the 461 and my idle was a bit high so I adjusted it down to about 2700 rpm. Then I set the high mixture so it ran at 12,500 rpm unloaded. Stuck it in some fir logs and it four stroked until it was in the cut, so I am thinking all is good. It starts and idles great. The specs I found for the 461 seemed to indicate an idle of 2500 rpm and WOT unloaded at 13,500 rpm. I set the high a bit lower than the specs just to be safe. Thanks for all the help.
 

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