Block Heater in DD 8v92 TA DDEC

[Hat52MY]

I have (what I believe to be) the Hatteras Factory installed block on my DD 8v92 TA DDEC engines. They block heaters have worked well. However, this past week when I flipped the breakers the port engine heater does not appear to be working (no heating). Starboard engine block heater works fine. Does anyone have a possible trouble shooting list to best determine why the block heater has stopped working. I have not confirmed but my understanding the location of the heater element is on the front left of the engine block behind a 4-bolt plate. In addition to possible trouble shooting list, can anyone confirm this is truly where the block heater element(s) is located on a DD 8v92 TA DDEC? Thanks, appreciate the help and insights!

Best regards,
--
David

[GJH]

See the other block heater thread for pictures of where they are on my non DDEC 8v92 engines. Quite possibly yours is different. Try feeling around anything that looks like my pics on the engine that has a working one and you will find the hot spot. An IR thermometer helps too.

[Hat52MY]

George - Thank you for the reply. I read the other post, did not realize at the time the pictures were of a 8v92. Thanks for the help on the possible location. Any addition thought on trouble shooting? It's my thought that unless the heating probe is defunct, there must be a short or loose wire connection. Are there any other possibilities?

[eze2bme]

Just a thought ... Is there a fuse in the heater circuit?

[Hat52MY]

Each block heater is on a dedicated breaker. You make a good point regarding a possible in line fuse. I have not had a chance to trace the wires (trying to get all of my ducks in a row before diving in).

These are DDEC engines. If I remember correctly, there is a "Smoke Control" setting within the DDEC system. Is it possible that the block heaters are tied into the DDEC system "smoke control"? Or is this a stretch?

[Bill Root]

OK. I'll bite. What's DDEC? Guess: Detroit Diesel Emission Control? How would one know of the engines on their boat were so equipped?

[GJH]

Electronic Control.

[Hat52MY]

Bill - DDEC stands for Detroit Diesel Electronic Controls. There are a numbers of threads on the site that discuss DDEC in detail - pros, cons, etc. In short you either love'em or hate'em. I must admit I was skeptical of the electronics at first but love'em as they allow me to monitor all sort of different aspects of the engine....maybe it is just the computer geek in me that has crossed over into the engine room. ;-) The easiest way to tell if you have DDEC installed you have an electronic control module (no analog gages) on the bridge.

In any regards, I am attempting to determine the following regarding the block heater:
1) physical location of the block heating element (this may have been answered, will know later in the week)
2) possible trouble shooting steps (or insights) of anyone who has been down this path before or anyone who might have some creative idea in trouble shooting
3) If the block heater was possibly controlled by DDEC and possibly by the "smoke control" setting.

[GJH]

I've got the shop manuals, which include the DDEC models, when I get a chance I'll look to see if there is anything in there.

[MikeP]

After the breaker/fuse checks...

Can you get multimeter probes onto the heater's connections at the engine? If so, disconnect the wires and probe the heater connections with the meter set on resistance. You should get virtually no resistance (literally a short circuit) or a couple of ohms at most. If you show an open circuit (infinite resistance), then the heating element has failed.

Now Connect the multimeter set to ac volts to those wires that you disconnected from the heater and turn on the power - you should see 120vac or thereabouts. If not then move up the wires to the succeeding circuit connections until you do see 120vac. THe problem is between those two points.