Timing Marks on my SOM flywheels

[Hugh Conway]

@ TxBlacksmith:

Gary said "We use a plate steel puller specially cut and hardened with a slot that is assembled over the key and it rotates into the space between flywheel and the ear on the key".
I bought one of those, and it has worked very nicely. This type has the advantage of pulling the Gib key while at the same time pushing the flywheel away. I believe it is more effective than a puller that works by pulling the key against the end of the crankshaft. For reluctant keys, solvent, time, and patience will usually do it!

If Gary cannot supply one, look below: It is a good tool to have, when you need it, you need it!

 Here's a link to DEV in India      http://lister-petter.devprecisionengineers.com/lister.htm

 A picture of the puller here    http://www.centralmainediesel.com/order/Gib_Key_Puller.asp?page=Gib_Key_Puller

 If you are in Canada, check here      http://www.justliveoffgrid.com/SpareParts.html  Remember, these prices are in $CAD, so if in the U.S. you will have to figure in the currency exchange.......we are about 30% less on the USD. I have one from here, works well.

Cheers,
Hugh

[TxBlacksmith]

Thanks for the info,  While we are talking about flywheels, what is the most common way to correctly measure
the RPM's?  Perhaps a mark or line on the flywheel for an optical tach?

[dieselgman]

I have seen an original Lister accessory that responded to engine vibrations to indicate rpms. Not sure how accurate and not too common - collector's item now. The modern factory used an optical reflector on the testing flywheel, dead-on accurate. Most of the electronic governors use a magnetic pickup that grabs a signal from the starter ring gear. Those can be tuned to a very precise setting and ultra sensitive. As a power generation tech, I always go with frequency at the generator head. That is what really matters anyway.

dieselgman

[Hugh Conway]

@TxBlacksmith
For testing, probably as Dieselgman says use a bit of maths on the flywheel/generator pulley and calculate RPM by using frequency.

I was fortunate to find something like this mechanical tach on ebay. http://www.ebay.com/itm/JONES-INSTRUMENT-CO-MDL-1600-X-2-0-1000-RPM-MECHANICAL-TACHOMETER-TESTED-/141889186229?hash=item21094129b5:g:2gQAAOSw~otWd3WN

Mine has a greater operational range and more attachments, but is similar, and Swiss made.  Works on just about any rotating device, and cost little.
Nice piece of gear to have in the drawer.
Cheers, Hugh

[EdDee]

Hey TX,

I do it old school... count the exhaust pulses in sets of four using my fingers to tally them off.... when I get to 40 pulses, it equates to 80 revs... of course you need a cheap watch to get the time taken for the test.... With a bit of practice, you will be surprised how accurate you can get...  Works quite well for me up to about 900 rpm, then it goes a bit awry....

Cheers
Ed

[dieselspanner]

Hi Guys,

For a cheap, and I mean cheap - less than three quid from China! - rev counter set the wheel circumference on a Fleabay cycle speedo to 1667mm then the display to kilometres and Bob's your mothers brother.

A couple of small brackets and a small neodymium magnet inside the rim of the fly wheel, then multiply the readout by 10.

Get a posher one and you can use it as an hours run meter and all sorts of other things.

If in doubt Google it.

Mine works!

Cheers Stef

[dieselspanner]

Further to my last post,

I've just used another cycle speedo to check the out put revs on the gearbox of my Dutch barge and it clocked up to 980 rpm with no problems, can't get cheaper, surely?

Cheers Stef

[BruceM]

A strip of reflective tape on the flywheel and generator head pulley with an optical tachometer does the job well.
This is the one my neighbor just bought for $13 and it works as well as my more expensive unit:

http://www.amazon.com/AGPtek%C2%AE-Professional-Digital-Tachometer-Contact/dp/B004Q8L894/ref=sr_1_1?ie=UTF8&qid=1456683683&sr=8-1&keywords=optical+tachometer

[Tom]

Good price on the tac, but the same price for 10 strips of reflective tape is outrageous.

[38ac]

I have a photo tach  but like everything else around here that uses batteries and doesnt get used every other day the darn thing is dead every time I pick it up

My most used tach is my old Stewart Warner contact type that I inherited from dad. The are always on Eaby for $15-50 and always work. Not the best if you need speeds with in .00236%  but plenty good enough for the bulk of my work.

[BruceM]

The optical tach above comes with one strip of tape.  They will work with plain white tape but not as well.