Tachometer........ Buy One Or Not???

[davefr]

Chris,
I'm absolutely no expert at tuning chainsaws. All I can say is that exact tuning relies on a number of observations. The tach. the sound and the speed of the cut.

When they all come together then the saw is running pretty darn good.

Unfortunately there is no "cook book" formula to ensure a perfect tune. I thought the Madsens method was pretty good until Andy told us it will almost always result in an under performing saw. If anyone has a perfect method it should be a sticky!!

 

[danrclem]

I bought this one; http://www.amickssuperstore.com/DTI...chometer_Tach_p/dti tech-tach tt-20k tach.htm It seems to work well and I am satisfied with it. It will also work with four stroke engines if a need arises.

 

[cjcocn]

I'll just pick you up on this one point.

Running with a blocked/dirty air filter does not cause a lean condition.

Think about it, lean = too much air and not enough fuel

A block filter means not enough air

Therefore you are running rich

LOL .... See? There you go right there. I'm still new enough to have to think things through before typing .... something that I obviously did not do with that one!

Thanks for clearing that up, Dan.

 

[Stihl051master]

Now one other question - am I the only one who tunes by plug color? What I've always done when tuning any two stroke be it a snowmobile, bike, saw, etc. is dial it in by ear and "feel" depending on what it is. Run it all all rpm ranges and jet/adjust accordingly. Then I remove the plug and check the color just to be sure I'm not running too lean. It's easy to see how your engine is running by looking at the plug color. Nice golden brown and you're good to go, "wet" and too dark and you're too rich, carbon-y black and fouled you're running too much oil mix, lt gray-white =too lean, richen it up to avoid certain disaster.

I'm still thinking of getting a tach just to see what RPM's I'm running - I think it would be a handy tool. I just redid an 026 and performed some mods and I want to see where I'm at.

 

[psquared]

Go for it

Posted by danrclem
I bought this one; http://www.amickssuperstore.com/DTI_...20k tach.htm It seems to work well and I am satisfied with it. It will also work with four stroke engines if a need arises.

:agree2:

I bought the same tach last week from Amicks and love it. We've got 5 2-strokes and 3 4-stroke small engines around here. It's a great tool and I have seen some opportunities to improve how these engines were running from ear tune only.

RPM may not be the whole story, but it's a big chapter.

 

[Ghillie]

I bought this one; http://www.amickssuperstore.com/DTI...chometer_Tach_p/dti tech-tach tt-20k tach.htm It seems to work well and I am satisfied with it. It will also work with four stroke engines if a need arises.

That is the one I am ordering later this week. Did a search on AS and a lot of readeing and this is the one that everybody seems happy with (price vs performance).

Now one other question - am I the only one who tunes by plug color? What I've always done when tuning any two stroke be it a snowmobile, bike, saw, etc. is dial it in by ear and "feel" depending on what it is. Run it all all rpm ranges and jet/adjust accordingly. Then I remove the plug and check the color just to be sure I'm not running too lean. It's easy to see how your engine is running by looking at the plug color. Nice golden brown and you're good to go, "wet" and too dark and you're too rich, carbon-y black and fouled you're running too much oil mix, lt gray-white =too lean, richen it up to avoid certain disaster.

I'm still thinking of getting a tach just to see what RPM's I'm running - I think it would be a handy tool. I just redid an 026 and performed some mods and I want to see where I'm at.

I have been tuning by ear but always double check with plug color. It has always been a good diagnostic tool for me whether working on automotives or equipment for a living to doing maintenance for my own equipment.

Always like to double check my work to make sure I haven't missed anything.

Fred

 

[milkie62]

Do what I did get the tach and 10 chains ----- comes to $ 196 and change

 

[xwray]

Lean or Rich?

SNIP.

Running with a dirty filter is another way to potentially ruin a saw by leaning it out, but I try and keep my filters clean.
SNIP:

I have seen similar remarks as I have tried to catch up on earlier posts. I always thought less air would result in an overly rich situation...do chainsaw/2 cycle engines respond differently than a four cycle engine (or maybe I'm wrong there too)?

thanks

 

[cjcocn]

I have seen similar remarks as I have tried to catch up on earlier posts. I always thought less air would result in an overly rich situation...do chainsaw/2 cycle engines respond differently than a four cycle engine (or maybe I'm wrong there too)?

thanks

xwray

No, you are not wrong. I was wrong when I posted that and I had it backwards.

A dirty filter will reduce the amount of air and will result in an overly rich situation.

 

[Ghillie]

I have seen similar remarks as I have tried to catch up on earlier posts. I always thought less air would result in an overly rich situation...do chainsaw/2 cycle engines respond differently than a four cycle engine (or maybe I'm wrong there too)?

thanks

Yes, it richens up the mixture.

Fred

 

[Tzed250]

I have seen similar remarks as I have tried to catch up on earlier posts. I always thought less air would result in an overly rich situation...do chainsaw/2 cycle engines respond differently than a four cycle engine (or maybe I'm wrong there too)?

thanks

xwray

No, you are not wrong. I was wrong when I posted that and I had it backwards.

A dirty filter will reduce the amount of air and will result in an overly rich situation.

Yes, it richens up the mixture.

Fred

That is why you always tune with a clean filter. Then as the filter gets covered the tune fails-safe.

IMHO, A tach, for most saws, is an accessory not a necessity...many modded saws need them because the two-four break has been moved much higher than stock.




.

 

[Wirenut2266]

Use a Fluke???

I have all these Fluke meters layin around, I would still like to know how to use them as a Tach. I know it's possible, just don't know if it can be done with regular leads, and meter range setting???/ Come on, give a guy a bone

 

[Tzed250]

I have all these Fluke meters layin around, I would still like to know how to use them as a Tach. I know it's possible, just don't know if it can be done with regular leads, and meter range setting???/ Come on, give a guy a bone

I have a Blue-Point DMM that has a dedicated tach function.

 

[Ghillie]

I have all these Fluke meters layin around, I would still like to know how to use them as a Tach. I know it's possible, just don't know if it can be done with regular leads, and meter range setting???/ Come on, give a guy a bone

I have an old Fluke 88 but I never bought the tach pickup (or I lost it 10 years ago ). I would like to use it for a tach also but I don' want to have a $500 meter rattling around in my truck toolbox.

That's why I decided to go with the TechTach 20k from Amick's.

Plus the fluke is a little bulky for how I think I am going to use it. Strap it to my arm to watch rpms in cut and other tom-foolery.

Fred

 

[Ghillie]

I have all these Fluke meters layin around, I would still like to know how to use them as a Tach. I know it's possible, just don't know if it can be done with regular leads, and meter range setting???/ Come on, give a guy a bone

What is your model of fluke and what kind of settings/ranges does it have?

I believe you can look up a manual for the meter on their website.

 

[Mad Professor]

Never tuned with a tac. I run the same gas/mix on all my saws and tune them to the same mix.

I set them so they just don't blurb/4-stroke with the bar burried in hardwood (e.g. start rich until it cuts good, stop there)

Exhaust look real nice with this method, very light tan, pistons clean with no carbon.

 

[Wirenut2266]

Ghillie: I have a Fluke 87, 88,and a 787 process meter. Yeh, went to Fluke site, not real clear. Doesn't say a for sure "yes" or "no" as far as working. I would assume process meter will would, that thing will measure a "fart" if it had too. Left new thread on fluke forume, will see in a day or two. The Fluke inductive pickup kit is only around $50, so hopefully it will work

 

[Wirenut2266]

Question Answered:

Yup: If you have a meter with Frequency Range on it, no problem. A little math needed though. Since frequency is measured in 60 cycles per second, the Fluke will not readout lets say 14,500.

The display will read 241.7Hz. = 14,500 rpm

(241.7 Hz x 60 cycles per second = 14,502 rpm's

For me, since I have 3 high end meters in trucks, what's another $50-$75 so I can play a little more at home with one of them. If I owned a shop and used quite often though, I would prolly just by tach, and no calculator needed. But a hack like me, this will be just fine! Time to go shopping

 

[Ghillie]

Yup: If you have a meter with Frequency Range on it, no problem. A little math needed though. Since frequency is measured in 60 cycles per second, the Fluke will not readout lets say 14,500.

The display will read 241.7Hz. = 14,500 rpm

(241.7 Hz x 60 cycles per second = 14,502 rpm's

For me, since I have 3 high end meters in trucks, what's another $50-$75 so I can play a little more at home with one of them. If I owned a shop and used quite often though, I would prolly just by tach, and no calculator needed. But a hack like me, this will be just fine! Time to go shopping

Sounds good, I thought they were more than that. I'll have to dig my 88 out and make sure it still works, haven't used it in a few years... Last time I worked on a vehicle with an ECM.

Thanks for the info!

Fred

 

[Wirenut2266]

Ghillie: If you Fluke display ever goes bad, let me know. There quite easy to fix. Fluke will charge you $385 and it is only 10 minutes to fix with a pencil and eraser!!!! They do that to try and force people to buy there latest and greatest, which is okay now, since all there new meters have a lifetime warranty.