How can I add a tachometer to my engine?

[cowboy]

I would like to know what RPM my engine is running at.    I've read that they are most efficient at 600-650 RPM and can totally frag at higher RPM's.      My governor is a bit lazy,   and doesn't seem to respond to changing loads as well as I would think it should.     I would be heart broken if my 6/1 blew up,  but maybe worse if I was next to it when it did!   Still trying to sort this thing out and get it providing power here at the ranch.   Still have a few months before Hurricane Season gets here.    Any help or ideas would be greatly appreciated.   What's everyone else doing about this?    Thanks in advance.

[Tijean]

If you are generating AC what you most need to know is the frequency. For example my kill o wat meter shows average 60~cycle so I know my generator is turning 1800 rpm. The pulley diameter ratio to the flywheel is 1:2 so my engine is turning half the gen. speed or 900rpm. Although I dont measure it directly I can calculate quite precisely what engine speed is.

[cgwymp]

A/C frequency is probably the most definitive, but if you want independent confirmation, you could also do something like this:

http://www.instructables.com/id/Tachometer-made-from-a-bicycle-speedometer-cycloc/

[veggie]

You could install a Tiny Tach diesel Tachometer/Hour Meter.

http://www.tinytach.com/tinytach/diesel.php

veggie

[buickanddeere]

  Thanks Veggie. I've been looking for exactly that kind of tach.

[cowboy]

How does that Tiny Tach work?   On the gas it's easy, spark plug wire.    On the diesel?  I looked on web sight but didn't see explanation.

[veggie]

I think it uses a dopler sensor.
There is no battery required for the diesel version.
Somehow the signal is induced into the pickup wire.
It's also a special wire (coaxial).
See the Q/A section of their website.

veggie

[Tijean]

I think it is  piezoelectric effect; triggers on the acoustic shock wave when the injector cracks. There have been plans to use an electric guitar pickup as a sensor to trigger a regular inductive timing light.

[LowGear]

My Witte was jumping all over the place until I got something like this:

http://cgi.ebay.com/Smiths-ATH4-Machinist-Handheld-Tachometer-0-10000-RPM-/160543590776?pt=LH_DefaultDomain_0&hash=item256124c978

I thought the technology fitted my '52 unit.  But this one would be a cheaper altermative.

http://cgi.ebay.com/LCD-Digital-Laser-Photo-Tachometer-Non-Contact-RPM-Tach-/280619167092?pt=AU_B_I_Electrical_Test_Equipment&hash=item415634ad74

Casey

[Horsepoor]

Cowboy,

Noticed your reference to hurricane season. Do you live in south Florida?

Bruce

[squarebob]

Here is what I use

http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXPT31&P=ML

$22.00

It is set up for a 2 blade or 3 blade prop. My flywheel has 6 spokes, so set it to 3 blade and divide the reading by 2.

1300 = 650 RPM

Bob

[rf]

 Hello to all, I use this unit ( http://store.qkits.com/moreinfo.cfm/MXA019 ) it's only a resolution of every 100 RPM but if you add 10 reflectors to the flywheel and cover the last digit on the display the readout hovers around the 650 mark. Speed is confirmed with a hand held photo electric unit. Final RPM / Hz. is tweaked with a Kill-A-Watt.
 Works good enough for me. I can't remember but with the enclosure and shipping I believe it was less than $50.00 in 2007
It also can be programed for hi or lo RPM triggers. But if you don't have constant power to the unit the settings are lost.
 For what its worth:)

RF

[cowboy]

Bruce, we are just north of Houston, TX.    Out where we live there are so many trees that get blown over in the hurricanes that severe power interuptions are common.    After Ike we were told that we would be without power for 12 weeks.   We got lucky,   they started on our side of the county and our power was back in 8 days.    Made us get serious about an economical long term solution.   That's why we bought the 6/1 and are trying to get it sorted out in case we have to make our own power for a long time.     We need about 2-400 gallons of water per day for the cows and we need to run the freezers at least 30 minutes 6 times per day.    A 6/1 CS diesel seems like  the ONLY reasonable choice.    Just don't tell my wife how much fun they are!

Cowboy

[wagspe208]

You could install a Tiny Tach diesel Tachometer/Hour Meter.

http://www.tinytach.com/tinytach/diesel.php

veggie

Veggie, do you have one of these in operation? What size are our fuel lines?
I have a tinytach on a honda generator. I added for the hour meter mostly as it is an inverter piece. It works great on the gas piece.
Thanks
Wags

[Veggiefuel]

Wags,

I can only speak for the 6/1 and 8/1 GM90 Listeroid engines.
The fuel injector line is 1/4" OD.
(I suspect most Listeroids are similar)
This happens to be the correct size for the Diesel Tiny Tack (1/4 " model)

Yes I do have one. I bought it recently to add to my CHP system instrumentation.
They system is currently under construction so I can't offer and run-time experience.
The company where I work has used them on Honda 1cyl. diesels with great success.

veggie