Tachometer

[Mike E-W]

Has anyone fitted a Runleader digital Tachometer or similar I want to fit one to a BMC1800 

[GUMPY]

Used a tinytach for years on my last boat

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

Ecxellent 

[Tony Brooks]

32 minutes ago, Mike E-W said:

Has anyone fitted a Runleader digital Tachometer or similar I want to fit one to a BMC1800 

 

Without a model number one can't be sure but those I looked at on Ebay etc. specified petrol engines so are probably coil connection sensed. Not good for a diesel. Diesel ones are usually at least twice the price. You also need to ensure the alternator has a W terminal or have a phase tap fitted to it.

[WotEver]

35 minutes ago, Tony Brooks said:

 

Without a model number one can't be sure but those I looked at on Ebay etc. specified petrol engines so are probably coil connection sensed. Not good for a diesel. Diesel ones are usually at least twice the price. You also need to ensure the alternator has a W terminal or have a phase tap fitted to it.

Every one of those Runleader tachos that I’ve seen online has been induction pickup. I’ve never seen a diesel one listed. 

[Tony Brooks]

6 minutes ago, WotEver said:

Every one of those Runleader tachos that I’ve seen online has been induction pickup. I’ve never seen a diesel one listed. 

That's the trouble for me because the words "inductive pickup" to me means things like crank or cam position sensor as found on modern ECU controlled cars. If so that would work but how many of us would happily drill and tap the flywheel housing and then get the sensor in the correct position relative to the flywheel teeth. It may also mean it comes in a kit with a "spider" you fit behind/in front of a suitable pulley and mount the sensor close by.  The lack of info about what it actually means makes me suspicious. In both cases I suppose it would work on a diesel if you could get the bits mounted properly.

 

Without more info I still think they are coil wire sensed.

[WotEver]

1 hour ago, Tony Brooks said:

That's the trouble for me because the words "inductive pickup" to me means things like crank or cam position sensor as found on modern ECU controlled cars. If so that would work but how many of us would happily drill and tap the flywheel housing and then get the sensor in the correct position relative to the flywheel teeth. It may also mean it comes in a kit with a "spider" you fit behind/in front of a suitable pulley and mount the sensor close by.  The lack of info about what it actually means makes me suspicious. In both cases I suppose it would work on a diesel if you could get the bits mounted properly.

 

Without more info I still think they are coil wire sensed.

I believe the ‘inductive pickup’ works simply by wrapping a wire around a plug lead. It picks up the EHV pulse and converts it to rpm. 

[GUMPY]

That's why the Tiny Tach is so clever It attaches a transducer to an injector line and is triggered by the pulse of diesel going through the pipe. It effectively measures the expansion of the pipe as the diesel passes. No messing around with W terminals and trying to calibrate the rev counter........

4 hours ago, WotEver said:

Every one of those Runleader tachos that I’ve seen online has been induction pickup. I’ve never seen a diesel one listed. 

http://www.run-leader.com/index.php?product/info/11/196/202/101

 

[WotEver]

34 minutes ago, Loddon said:

 

http://www.run-leader.com/index.php?product/info/11/196/202/101

 

Cool

 

 

Price?

[Tony Brooks]

1 hour ago, Loddon said:

That's why the Tiny Tach is so clever It attaches a transducer to an injector line and is triggered by the pulse of diesel going through the pipe. It effectively measures the expansion of the pipe as the diesel passes. No messing around with W terminals and trying to calibrate the rev counter........

http://www.run-leader.com/index.php?product/info/11/196/202/101

 

I noticed that and then remembered a problem a garage equipment "tuning" equipment company had when developing a similar thing in the 60s. Apparent it worked perfectly in the lab and on the company trucks etc. but when they did a large scale test some operators reported problems. It seemed that other percussive happenings in poorly maintained/worn out engines could produce false pulses.