Suzuki DF140 + Garmin 721xs, bad idle...

[Ryds 695 Family]

connected my Suzuki DF140, 2011 to Garmin 721xs via NMEA2000.
I wanted to see motordata, but when I connected them the motor began to stall at idle and was near stopping. When I took off, the motor ran good until I wanted to go faster than 12 knots.... I couldnt rev more than approx 3500rpm.

When I disconnected the nmea2000 cable wich was connected in the back of my Garmin 721 nothing happened. Then I tried disconnecting the interface module wich was connected to a cable comeing from my motor, Bingo! the motor ran perfectly again.

What is the problem? (Pardon my english, Im from Sweden)

/John

[Moonlighter]

Hi John

I think that you may have a bad (faulty) interface cable. Or wrong version, the 2011 engine requires a cable version 2.9.4. This is the correct part:
https://www.brownspoint.com/store/pc...9-38p71396.htm


There is a small chance that the problem could be the network backbone is not set up incorrectly. But to be safe, we should verify that the netwoek is set up correctly. Can you take a photo of the backbone or draw a plan or diagram of its layout And post it here.?

[Ryds 695 Family]

I have got the right interface now, but from the start I was sent a wrong version.
The first interface just showed rpm, but the motor worked out fine.

I will try to make a drawing of my installation when Im in the boat.

Thanks!

[Ryds 695 Family]

This is how its iinstalled.

[Moonlighter]

Ok well that installation is sooooooo wrong I cannot believe it!

And it may well be the reason why your previous problems happened too.

I will find some diagrams later on how to set up a NMEA2000 network correctly and will post them here. If you see this message Before I do that, do some research yourself on how to set up a NMEA2000 backbone.

[Moonlighter]

Ok below is a link to a good guide to setting up NMEA2000 networks from Garmin. This guide shows the important aspects of how networks must be set up, this guide is generic, and applies to all NMEA2000 networks regardless of manufacturer.

Please read it and look at the diagram on the first page as it clearly shows how a network MUST be constructed, and where devices must be connected to T pieces.

I strongly suggest that you rebuild your network to meet the accepted network construction requirements as per this guide. You will need additional components, and it might be worth buying a “network starter kit” because they have all the components required and are usually far less expensive than buying the components individually.

When you have done that, test your engine again and I suspect that it will work properly, assuming that nothing has been damaged due to the incorrect installation.

https://static.garmin.com/pumac/Tech..._NMEA2k_EN.pdf

Please report back when its done and tell us the results.

[Ryds 695 Family]

Oh shit!
I need two T-connectors and one termination, then it should be great. The motor runs well and the GPS too, so if anything is wrecked then it must be the interface.
I hope I havent wrecked anything! I clearly see that I underestimated the rules of installation of NMEA.

Thanks for your answeres! I think this will solve it.

[Moonlighter]

Yes, shit is an understatement ! Lol!!

Thats the worst effort at setting up a network Ive ever seen. give yourself an uppercut hahaha!

I do hope there is no damage, especially to the ecu. Hopefully not.

Actually, you need 2 terminators (terminating resistors) - one at each end of the network.

For a network that has 2 devices (in this case, the Suzuki interface and the Garmin display), you need 3 T pieces (one for each device and one for power), 1 drop cable, a network power connection and 2 terminating resistors (TR).

It will look like this, if you think of the printed letter “T” as having a vertical leg and a cross at the top, it represents a networkT piece:

TR - T - T - T - TR.

The devices and power must only EVER be attached to the leg of the T’s. Attach the power to the T in the centre of the group of 3.

The T’s can directly attach to each other at the cross part at the top, in a nice neat line. Put a TR on the unused ends of the T’s at each end. The line of T’s set up like this is called the network backbone.

Good luck, fix up the backbone so its right, connect up the power and devices, and then test how the Engine runs and see what info you get on the display. You might have to reset network data sources on the Garmin to get it to show all the engIne data, this procedure is in the Garmin menu somewhere.

[Ryds 695 Family]

With the right interface and correct installation it worked of fine.
My installation wasnt that bad as I drawned. I had one more T that I had forgot and a termination.
Thanks Moonlighter!