Fast Tach issues

[MarkEagleUSA]

I picked up a Fast Tach this week based on comments and recommendations here on AS. Used it a bit this weekend to tune my 162SE and had some issues with it.

Trying to hold it with my left hand on the saw with the arrow pointing at the plug, it will randomly go crazy where the entire LCD turns on and it stops counting RPM's. It's almost like it's resetting itself. After a couple of seconds, the display will return to "0000" and it will begin counting RPM's again. It will do this occasionally when held in other positions as well. I even went out yesterday and bought a new battery thinking that might be the problem but it's still doing it.

I've sent an email off to Design Technology but was wondering if anyone here has experienced similar issues?

 

[TK]

I haven't had issues with mine like that, but I seem to always use my Oppama tach instead, better tach IMO. It is possible to have the FastTach too close to a strong signal, try holding it further away if you can.

 

[GUNDOC]

i have bought several from them,and only one was bad as you described, i dont recall his name but if you call the owner usually
answers, and he will send you another one no charge. good luck.

 

[weiland13]

coil

That saw doesn't have an rpm limiting coil does it? Does the tach go crazy through all rpms or is it at top rpm limit?

 

[MarkEagleUSA]

That saw doesn't have an rpm limiting coil does it?

I don't believe so.

Does the tach go crazy through all rpms or is it at top rpm limit?

Seems to happen more at higher RPM's, though it's also gone whacky at idle.

 

[o8f150]

mine will do that too once in a while,,, took a while to figure out the problem,,, I started holding closer to the spark plug wire and it works good

 

[MarkEagleUSA]

I started holding closer to the spark plug wire and it works good

If I held it any closer to the wire it would be under the top cover! :msp_wink:

It really seems to be more the position of the tach. In relation to the arrow on the front, if it's pointing down or to the right (upside down) is when it goes crazy the most. If held pointing left it almost never does it.

I'm beginning to think it's defective...

 

[Flintknapper]

mine will do that too once in a while,,, took a while to figure out the problem,,, I started holding closer to the spark plug wire and it works good

Mine is just the opposite, if I get too close to the spark plug (or wire) it goes all wonky, naturally too far away...and it won't read either, but 'position' has made no difference, like the OP's problem.

 

[3000 FPS]

I have one and have used it now for a couple of years. Never had any issues with it. Heck I even used it on my Honda generator to set the RPM's on it with no problem. I never use it for tuning though just checking to see what the final RPM of the engine turned out to be.

 

[Joe Kidd]

If I held it any closer to the wire it would be under the top cover! :msp_wink:

It really seems to be more the position of the tach. In relation to the arrow on the front, if it's pointing down or to the right (upside down) is when it goes crazy the most. If held pointing left it almost never does it.

I'm beginning to think it's defective...

Mines been ok. Open it up and make sure the battery is tight. That's about all you can do other than a return.

 

[MarkEagleUSA]

Open it up and make sure the battery is tight.

That's the first thing I did. Even cleaned the contact points with some alcohol, and I replaced the battery with a brand new one. Then I thought maybe I was holding it in a place where pressure was being put on the circuit board but that doesn't seem to be the case.

I'll wait to hear from Design Technology and see what they have to say.

 

[MarkEagleUSA]

I'll wait to hear from Design Technology and see what they have to say.

Here's the reply I got from DT:

The tach is getting too strong of a signal in that position.

You will need to hold it away , a little farther.

Try this and see if it doesn't help, You may have a unit that

is very sensitive or the saw has a very high EMF

We can check if for you and replace it if it has failed.

I didn't have a lot of time when I got home but gave it a quick test. Seems holding it further away does work for the most part. However, if I hold it anywhere over the flywheel side it goes bonkers... I guessing there's extraneous signals coming from the coil and/or module.

Hopefully tomorrow I'll have more time to play with it to determine what works best.

 

[RiverRocket]

Maybe you could put some electrical tape or something on the back of it so that you could hold it closer??
Just a thought?

 

[MarkEagleUSA]

The tach was sent back to DTI today so they can have a look at it. I tried it on 3 different saws and a lawnmower this past weekend and it was wonky on all of them.

 

[Jed1124]

I got mine a couple of years ago and same thing from day one. It would work but not well. Lot of crazy numbers and then it would work. I wish I would have thought of trying to get a replacement. Let us know how it turns out if you get another.

 

[KenJax Tree]

mine will do that too once in a while,,, took a while to figure out the problem,,, I started holding closer to the spark plug wire and it works good

The problem was it won't tell you how fast your midget chicken legs are moving trying to catch sheep.

 

[blsnelling]

Mine is several years old and has been problem free.

 

[pops21]

Mine just started doing this same thing last time I used it a few weeks ago. I was thinking the battery was dieing? Haven't had time to get a new battery. But now after this thread I'm starting to think something might be wrong.

 

[w8ye]

I had a Fast Tach for about 3 years and never any trouble with it.

 

[jus2fat]

Wow..What freaking timing...I was just about to 'pull the trigger' on one...no problems seen reported before

What the hell - - too close- - too far away..?? - I've seen Brad's videos with right up to top cover..and solid reading

I hate surprises..and especially bad ones - This purchase will be on hold until more clarification.

Dealer needs to rectify the problems experienced and then fix them..then publish corrections (if any)

I don't think the seller is the actual manufacturer..soo..he's caught in the middle..but still responsible to the buyer.

Just sayin'..$85 is not that heavy IF it works great...BUT for $85 you expect it to work great..and NO surprises..!!
(FISH...come back..!! - I'm carrying 'your' freaking world on my shoulders..!!)

J2F