Replacing the Tach; Universal 5411

[jrhamp]

The previous owner of the 1982 Catalina 30 removed the tachometer. He indicated a "feel" for the engine was adequate while adding interior panel where the tach was originally located.

That said, I wish to install a tachometer on the Universal 5411. I read an earlier post about the Tiny Tach for Diesels. See link here from manufacturer http://tinytach.com/diesel.php

Note the transducer is connected to the diesel fuel line. Not certain I understand the physics of the fuel line over the alternator as the primary source of RPM generation.

Does anyone have experience with this situation and/or this replacement tachometer.

Are their wireless tachometer available.

Thanks in advance/Randy

 

[jrowan]

Sorry mate, but the Catalina 30 with the 5411 diesel never came with a tachometer as standard equipment. This was an aftermarket modification by a previous owner. It was not standard equipment until years later with the upgraded Seaward engine gauge panel, which I believe came with the 3 cylinder Universal 25 engine. I don't understand how the fuel line would give you RPM reading. Usually the tachometer reads the output from the spinning of the alternator. The revolutions of the alternator create the signal read by the tach. gauge. There is a terminal on the back of the alternator specifically designed for the alternator signal. You have to research what electrical terminal to use, based on the alternator that came with your engine. I have the standard 35 Amp output model. I don't even have a tachometer gauge on my boat, and I don't feel that I really need one. You can indeed hear the sound of the output that the engine makes. Once the engine has created maximum speed that the prop can handle, then that is the max speed you should apply throttle for. Excess rev's over the point of where the engine can reach max speed over ground via GPS is just wasting fuel & overloading the engine. With a clean hull & prop, I can manage about 5.5 to 6.o knots of speed, over flat water. Our 5411 diesels are not that powerful, but are damn tough & reliable. Cheers.

 

[rbmcintire]

There wasn't a lot of clear documentation at that website, but I guess I inferred that it mounts on a fuel injector line and uses an ultrasonic-type pulse counter. I couldn't say if there was actually room to install it but it would theoretically work. IMHO, I'd go with the well known path and use the alternator signal and an analog tach. For our boat, we have some old intermittent gauges and I have this image in my mind's eye to build a new cluster using teak.

Rob

 

[Stu Jackson]

If you still have the old Motorola 35 or 55 A alternator, here are some wiring diagrams I drew when I upgraded to a 100A alternator and external regulator. The sketch shows the wiring at the back. The tach doesn't have to be "in" your panel, you could mount the gauge anywhere you like that's visible at the helm. The earlier advice is spot on.

http://c34.org/bbs/index.php/topic,4432.0.html

 

[jrhamp]

Thanks to all...especially jrowan. I had assumed the " located "gauges" on the starboard side just off to the right from the entryway..were in fact, a tachometer. Now I realize the 1982's did not come with a tachometer. Thanks much for the clarification.

I am very new to this boat, so understanding the configurations of the boat remain a simple challenge.

The Tiny Tack according to the response to my email "reads" the fuel flow..however, the company said, the pressure is low and the readings are sometimes not correct. I shall not purchase this device. Another device attached to the alternator and senses the revolutions, hence RPM.

But, that said, I shall forgo both...and not "replace" the tachometer and go with the feel and sound of the engine. I hope to back in Key West by Saturday, 22nd...will be staging in Germany for the flight back to the "Land of the Big PX". Thanks much for taking the time to comment/Randy