Need a good Tach

[Lakeside53]

Has anyone used this PT15 Tach on chainsaws? The price is definately good and it seems to support high RPM engines.

It would be cool to mount one of these on the back of the airfilter to watch closely what happens "in the wood".

 

[stump doctor]

It's the way the flywheel based magneto drives spark for two cylinders. Both spark whether twice whether they need it or not. Saves needing a distributor. Many, if not most of the two cylinder engines work this way - My 15HP Kawaski and 16HP Vangard both produce two sparks per revolution - and I initially bought the wrong tach!

So you would need to set the PT14 tach above on setting S3 in order to give you the correct reading for a chain saw? S3 A spark firing every 180 degrees or two per full 360 degree revolution.

 

[lesorubcheek]

Thanks Lakeside for the enlightenment,

This makes sense. I was only thinking single cylinder. The only multi-cylinder engines I've worked with are bikes and autos. I never heard of this idea before. Its a good feeling to learn a new concept.

Dan

 

[Drive_1305]

Some of you guys help me figure out this PT15 tach http://enmco.thomasnet.com/item/enm-counting-instruments-tach-hour-meters/tachometer/pt15c2?&seo=110

It shows a capacity of 24,000 rpm which Im sure means it displays 0 to 24,000. Then it shows compatibility of 2C engines(sparks once/rev). Sparks once/rev is the way 2 cycle engines fire. So wouldn't this tach work for saws? I know the PT14 would be better but its more expensive.

Also the device doesn't know what engine your connecting it to. It could fire once/rev, twice/rev or whatever -it counts sparks. So if you used it on a twice/rev engine and took a rpm reading and then either multiply or divide by 2( or maybe 4 duh...need to think about it) wouldn't you get the true rpm of the engine. Its not the best way but for $24 oh well

One guy above said he understands that a 4 cycle fires once/2rev, thats what I always thought and what small engine books show. But on the typical small 4 cycle engine doesn't it create voltage and a spark every revolution? What would keep it from it doing so? I asked a mechanic this at another forum and he said it did, it creates a "wasted" spark on the exhaust stroke.

 

[t_andersen]

Baileys has a tach at 69.95$. It won't let you change the battery though.

http://store.baileys-online.com/cgi-bin/baileys/1112?mv_session_id=MfvIqAgq&product_sku=17122

 

[Finnbear]

I looked at the website and the PT14212 is for what's referred to as a single cycle engine with a spark of twice per revolution. Now I understand a 2 cycle with a spark of once per rev and a 4 cycle with a spark at each 2 revs, but what engine runs with a spark twice per revs? I must be missing something obvious here?

Dan

2 cylinder air cooled? Some 4-stroke single cyl engines spark every rev and thus have a wasted spark every other rev but it was cheaper to design an ignition that fires every rev than every other.
Finnbear

 

[hammer0419]

I just called Design Technology and talked with steve. I was going to purchase the Tech Tach 20k but he suggested the "Fast Tach" they make. It is not on the web site. It is a third the size of the Tech Tach but with the same size display for $85. I told him I was just looking for something to maintain my saws, string trimmers and leaf blowers and he said this would be perfect.

 

[TexasTimbers]

Well I just ordered the little $25 LCD 8010 gizmo. I'll let y'all know how it works.

 

[bump_r]

I just bought an Echo branded tach for $125. It looks identical to the Stihl EDT 5. It's made by OPPAMA Industry Co LTD of Yokosuka Japan, and is the "Pulse PET-1000". It has two settings, the 21:22 is for 2 stroke/single cylinder application and 4-strok /twin cylinder sherease the 22:44 is for 2-stroke/twin and 4-stroke 4-cylinder.

 

[cmontana]

ENM tachometer

I just spoke with Bob at ENM. He reported that they will be offering a "flat-back" version of the PT-15 in a few months for about the same price. The flat-back version will allow mounting with two-sided tape. You could mount this directly on the air cleaner cover! He also mentioned that with the PT-15, attaching the feed wire is not necessary as long as it is in close proximity to the signal.

 

[wagonwheeler]

Updates on Tachs

Lot's of tachs mentioned here and wondered if anyone has any updates on units they bought.

Chaser

 

[Lakeside53]

Stihl's telling us to get the EDT-7 and 8... Future "products" (hmmm... whatever they mean) will have a different ignition arrangement with 4 magnets.. Conventional tachs are going to misread the field reset magnet pulse as the main fire. Great..

No idea what "products" are going to need this, so it's not an issue as at today.

 

[ky-homelite]

I purchased a Fast Tach a month or so back. I've used it a handful of times. It seems to function as advertised. It's wireless, can read up to 20,000 rpm and has a replaceable battery unlike some tach's I looked at. For $65 you can't beat it. It gives you a good piece of mind to know you're within spec.

When I called the company, I was originally looking at the Tech-Tach TT-20K but I spoke with a fellow (I believe his name was Steve) and he suggested the Fast Tach instead. The Fast Tach is not listed on the website. As a matter of fact, the fellow I spoke with told me if I wasn't satisfied with the Fast Tach, I could return it for a credit and get the Tech-Tach. Good product and a great company to deal with. www.tinytach.com if you're interested.

 

[wagonwheeler]

Thanks Kentucky! That's one in particular I was wondering about.

Chaser

 

[nisse]

Has anyone tried the PT15 yet? It's dirt cheap compared to other brands, and if it show RPM's accurate it's good enough for me.

But I like someone else to try it first...

/Nisse

 

[Evin]

I have just purchased the PT15B2 and they are shipping it today... $24 and no shipping cost in the US. Hopefully it will do the trick. It is made by ENM,
http://enmco.thomasnet.com/item/enm-...=prod&filter=0
it reads to 24k.

:greenchainsaw:

 

[nisse]

Thank you Evin, that's the one I was thinking of. Pls let us know how it worked.
Unfortunately there's no free shipping to Sweden..strange..:biggrinbounce2:

/Nisse

 

[TexasTimbers]

Ihave fooled around with mine a little. I can't get it to make qany sense. It's the LCD 8010 made by ENM I mentioned back in September. There are 3 diffeent "sub' model categories listed on the back of it.

LCD8010-1C
LCD8010-2C
LCD8010-4C

The 4C is checked to indicate that is the model I have.
The instructions tell me I also have the "Y" type. As opposed to the 'X' 'XR' 'YR' 'Z' or 'ZR' :bang:

Bottom line my tach is for a 4 stroke engine not my 372XP! I doubt I could hook it up anyway and just divide by two because it probably don't work that way and I dount this tack will go up to nearly 30,000RPM which is what it would be seeing at one spark per crankshaft revoultuion. Unless I am confused. this is always a big possibility.

 

[TexasTimbers]

Well it works it's just that it is useless. i just got thorugh using it and it limits out at 9999. Wrong model.

 

[TexasTimbers]

Well I just ordered the little $25 LCD 8010 gizmo. I'll let y'all know how it works.

I forgot to update this post. The one they sent had a part number on it "PT15B2" and did not read correctly so I called the company (www.enmco.com) and they said "Oh that is not the right one. Was on hold for long time while they researched this. They sent out a new one. After I paid for it of course. This one was the Model LCD 8010-4C with another number LCD8010Y07.
I tried it out and of course it did not work because it is for a four banger.
i called the company back, got a supposed tech who said "Oh that original PT15 should work you should just have to solder a wire on the upper left dot of solder".
What a joke. I'm working on memory here, there are 3 unused "dots" of solder on the back of this thing maybe he said lower left but whatever. I should not have to do this. I asked if I could send them both back for a refund and you guessed, of course not.

Don't use this company or their products. They suck.