Engine Guages and Tach for M35B

[Robert P Adams]

Got a surprise this spring starting the M35B in my Cat 350-2006 hull #378. Engine runs fine but gauges and tach non operative. Buzzer works fine when keys left in ignition switch after killing engine. Pulled panel off of wheel housing to check to any disconnected wires-found none. Even replaced ignition switch-no change. Any thoughts? Intuition tells me the problem is originating someplace else.

[scott.monroe]

Morning Robert,

Two possible sources for your problem, either power to or ground from your panel. Easy things first. On the power side of equation, there is a breaker on the panel, small button on front of console, just double check that it hasn't tripped. It provides over-current protection/ power for the whole panel, although since your buzzer is working that solution is suspect, but worth a press. At some point you will have to check power to the panel to see if they are getting any. A volt meter would do that test. Attached pic of wire harness view down through compass, inset is color codes from pg 25 of operation manual. Check red and black with volt meter while battery switch is on. Should read 12v. If ok, turn on ignition switch then check red/white against black, should read 12v. But if you don't get 12 V on meter and since the engine starts from the panel / and buzzer works could be ground problem.

Ground problems could explain your symptoms. If the ground from the panel is compromised none of the gauges would work. The buzzer however, while getting power through the aforementioned breaker, is grounded via a different path, the switch on the engine (if oil pressure is too low, as when the engine isn't running, the switch is closed completing the circuit). I included a picture of the my 2006 panel wiring as seen down through the compass port. I highlighted the ground connection to the wire harness. Notice the corrosion on the black wires I found in my 2006. This is certainly a possibility, cleaning may help. If cleaning doesn't help you might have to track down where the black wire terminates and see if its disconnected or corroded.

Hope this helps.
Scott

[KenKrawford]

Can’t add much to Scott’s reply. Nicely done !

[Zephyr307]

My problem is similar to Robert’s above, but began with occasional chirping from the oil pressure alarm. While trying to track down the cause of that problem, I had the engine running and control panel on the pedestal open when I noticed the tach and gauges (water temp, fuel and voltage) were no longer working, but the alarm still works! I have traced wires and checked continuity throughout the panel, to the alternator and solenoid as much as I am able and haven’t found a loose connection.

Scott mentions a button, or breaker, on the front of the control panel. My panel (2005, hull 307) doesn’t have one, thought it seems like some fuse must have blown or breaker tripped. I can’t find a fuse or breaker for the engine electronics in the M35b electrical diagram. (There are two CB’s integral to the engine and I have continuity through them.)

Two other possible related factors. The chirping began after I replaced the original 51 amp Mando alternator with a new 65 amp Mando. The output is great, but the tach became more sensitive (would swing from under reporting to over reporting) and then the occasional chirping started. Also, in January we experienced an oil switch failure and replaced the original with one with very similar specs from an auto parts store. It seems to be working well.

Any suggestions as to where the point of failure might be (or even how to further troubleshoot) would be greatly appreciated! We are down in the Bahamas and it will be long trip home without the gauges and with that d*** chirping all the way home!

Dave Strachan
Zephyr
Hull #307

[KenKrawford]

Dave, I've had a chirping alarm following the replacement of the buzzer. Mine only occurs after the engine has been run a a while. I've checked all the panel connections to no avail. Right now I'm just ignoring it.

Below is an image with the panel breaker shown. I'd be very surprised if your panel is different.

[Zephyr307]

That was it.... this is a relatively new boat to me and I thought for some reason that the button was a light associated with the blower. Once I pushed that button and the gauges were restored! I have not seen any reference to a circuit breaker in any of the documentation that came with the boat. Having spent several days tracing wires and checking connections, at least I am now much more familiar with my engine! As for the chirp, I will live with it, too.

Dave Strachan
Zephyr - Hull 307

[bobdelia]

Good Morning fellow 350 Owners. My Ignition Key switch failed, and I replaced it, but have no power coming into the control panel. The excellent posts have helped me somewhat, in that I now (after 19 years of ownership) know that there is a breaker on the Control Panel, but I have no power coming into the connection strip behind the panel. The schematic shows there is a fuse or breaker somewhere in the red power wire coming in from the alternator. Has anyone found that? I looked all over. Any input would be appreciated. Thanks! Bob

[TBOT422]

I'm not near the boat now. But, if you are talking about the 20 amp breaker shown on the schematic, ours is located in the engine compartment. My recollection is that it is somewhere near the fuel lift pump. It is breaker with a red button that is labeled "20".

Good Luck

[bobdelia]

Thank you for the quick response. I have whole 020. I cannot find any breaker switch in my engine compartment, and I’ve searched it thoroughly. Anybody with an early whole number have any suggestions? Thank you!!! Bob

[KenKrawford]

The circuit breaker that Gary referenced should be on the same bracket as the starter solenoid. I don't believe there's anything else around there with a red button. I'm not positive but I believe all C350's regardless of hull number have the Universal M35B engine. Here's the schematic from the manual -

[Pgtjs]

Hi there, my C 350, #392, has a Yanmar 3YM30 HP Diesel - special ordered that way from Catalina and commissioned in May 2006. It's a long story but my 350 replaced a 2005 C320 which Catalina took back under warranty and I asked for the same engine in a 350. I had a Universal 30HP diesel on a previous boat in the early 1990s and said never again. The 320s had Yanmars and I have to say Catalina was very gracious and generous in allowing me to move up to a C350 when they replaced the 320. I even got a personal call from Frank Butler at the time. There was nothing written about the 320 problem by mutual consent.

Cheers, Geoff. S. Taeko 1V, Semiahmoo WA.

[GRWhite]

Just thought I would post some pictures on the location of this circuit breaker. It tripped on me last week the engine stalled as well. I couldn't restart the engine since there was no voltage to the instrument panel. The service manual remedy is "reset breaker, if opens again check preheat solenoid circuit and run circuit for shorts to ground".