actual RPM's
 

I belive my tach is not reading properly. I have an albin 27 family
cruiser with a lehman diesel the rpms seem to exceed the redline by
alot 500 to 800 rpm (guessing) the tach stops at 4100. I don't think
the engine would go this high. I am trying to find something to check
the rpms so I can calibrate the tach or repitch the prop. Any help
would be appreciated. Paul, Cape Cod, MA

boater435 wrote:
I belive my tach is not reading properly. I have an albin 27 family
cruiser with a lehman diesel the rpms seem to exceed the redline by
alot 500 to 800 rpm (guessing) the tach stops at 4100. I don't think
the engine would go this high. I am trying to find something to check
the rpms so I can calibrate the tach or repitch the prop. Any help
would be appreciated. Paul, Cape Cod, MA

There is a little gadget that has a rubber tip and records revolutions
sort of like a micrometer or caliper. A friend had one and helped
me calibrate a tach that was not reading properly after a pulley had
been changed. You hold it against the crank pulley for a minute and
it tells you the revs.

Somewhere I have another that I found at a flea market, but can't find
it now. I seem to remember the word "Starette" stamped on it - they
made a lot of small instruments.

I got a laser one for that purpose. Just put a little piece of reflective
tape on the flywheel and aim the laser at it. I think I paid about $40 for
it, maybe you can rent one.

"Jeff" wrote in message
news:1125697229.b7089977ad2a2f0c9398117204ee43cc@t eranews...
boater435 wrote:
I belive my tach is not reading properly. I have an albin 27 family
cruiser with a lehman diesel the rpms seem to exceed the redline by
alot 500 to 800 rpm (guessing) the tach stops at 4100. I don't think
the engine would go this high. I am trying to find something to check
the rpms so I can calibrate the tach or repitch the prop. Any help
would be appreciated. Paul, Cape Cod, MA

There is a little gadget that has a rubber tip and records revolutions
sort of like a micrometer or caliper. A friend had one and helped me
calibrate a tach that was not reading properly after a pulley had been
changed. You hold it against the crank pulley for a minute and it tells
you the revs.

Somewhere I have another that I found at a flea market, but can't find it
now. I seem to remember the word "Starette" stamped on it - they made a
lot of small instruments.

On 2 Sep 2005 08:40:43 -0700, "boater435" wrote:

I belive my tach is not reading properly. I have an albin 27 family
cruiser with a lehman diesel the rpms seem to exceed the redline by
alot 500 to 800 rpm (guessing) the tach stops at 4100. I don't think
the engine would go this high. I am trying to find something to check
the rpms so I can calibrate the tach or repitch the prop. Any help
would be appreciated. Paul, Cape Cod, MA

Get a cheap non contact tach - perhaps one that reads a tape strip on
a shaft. Try it with an induction motor off load - they spin about
3590 or 1592 rpm.


Here's a note - an old note - that mentions this kind of device.

"On page 4 of the AIRCRAFT TOOL SUPPLY CO 1-800-248-0638
[great catalog]
there is a digital propeller tachometer, it is
hand held and works on 2-3 &4 bladed propellers. it has automatic shut
off, works to 45 deg. Pilots use it in the cockpit - its cost
$49.95!!!!!
aircraft tool supply
po box 307
1000 old US-23,
Oscoda, mi. 48750 "
####################################

Brian Whatcott

On Sat, 03 Sep 2005 00:34:29 GMT, Brian Whatcott
wrote:

Get a cheap non contact tach - perhaps one that reads a tape strip on
a shaft. Try it with an induction motor off load - they spin about
3590 or 1592 rpm.

Brian Whatcott

Make that, nearly 3600 rpm or nearly 1800 rpm.

Brian

"boater435" wrote in
ups.com:

I belive my tach is not reading properly. I have an albin 27 family
cruiser with a lehman diesel the rpms seem to exceed the redline by
alot 500 to 800 rpm (guessing) the tach stops at 4100. I don't think
the engine would go this high. I am trying to find something to check
the rpms so I can calibrate the tach or repitch the prop. Any help
would be appreciated. Paul, Cape Cod, MA



Dump it. Put in a $65 TinyTach! Here's the diesel model:
http://www.tinytach.com/tinytach/diesel.php

Even keeps up with engine hours, automatically. Runs 24/7 for a whole year
on ONE 9V battery...(c;

--
Larry

"johnhh" wrote in
:

I got a laser one for that purpose. Just put a little piece of
reflective tape on the flywheel and aim the laser at it. I think I
paid about $40 for it, maybe you can rent one.



Takes 30 minutes to install a TinyTach....
http://www.tinytach.com/tinytach/diesel.php


--
Larry

You have mentioned Tiny Tach before , Larry. They seem pretty impressive,
and now the diesel model.
Are they very accurate?

"Larry" wrote in message
...
"boater435" wrote in
ups.com:

I belive my tach is not reading properly. I have an albin 27 family
cruiser with a lehman diesel the rpms seem to exceed the redline by
alot 500 to 800 rpm (guessing) the tach stops at 4100. I don't think
the engine would go this high. I am trying to find something to check
the rpms so I can calibrate the tach or repitch the prop. Any help
would be appreciated. Paul, Cape Cod, MA



Dump it. Put in a $65 TinyTach! Here's the diesel model:
http://www.tinytach.com/tinytach/diesel.php

Even keeps up with engine hours, automatically. Runs 24/7 for a whole
year
on ONE 9V battery...(c;

--
Larry

"Garland Gray II" wrote in
news:NF7Se.106075$Ep.86997@lakeread02:

You have mentioned Tiny Tach before , Larry. They seem pretty
impressive, and now the diesel model.
Are they very accurate?



Digital....it's a pulse counter. It's as accurate as your quarts
wris****ch.

The first model was created for toy engines....jetskis, snow mobiles,
motorcycles, etc. I had one I transferred from jetski to jetski. It
didn't even connect to the engine! You wrapped its little antenna wire
around a spark plug wire and told it how many cylinders your engine had.
It picked up the pulses by capacitive coupling. Those had watch batteries
in them I don't ever remember replacing. The diesel models must have to
use a little more power, hence the 9V or DC power connection.

--
Larry

Larry, Thank you for the info on the tiny tach. I am going to order
one. Do you know if the transducer size (1/4" or 6mm) is found by
measuring fuel line? Paul