Official Caterpillar3116/3126 Thread

Strecker25 said:
I wonder, is it temp sensitive and turns on and off that way or does it switch on and shut off after a set period of time regardless?
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I've never seen a good description of the Air Heater (AH)control, but from reading the troubleshooting guides, this is what I came up with. The Control Module really is a "Black Box". Its mounted on the side wall of the junction box with a wire harness plugged into it. The inputs are a coolant temperature switch and an oil pressure switch, which are what it needs to do its thing.

This is the order of operation.

1. Air Heater Lamp Test - (Sea Ray didn't install these to my knowledge, so we wont see this). Lamp ON for 2 seconds. If the coolant is below 65*, the system should then go directly to the Preheat Cycle (lamp doesn't go out). If above 85* it would go off. No AH required.

Note: There is an optional temperature switch (Part # 7E-9425) which can change these temps to 120* and 95*, and there is an optional Control Module (Part # 4P6602) that has "different" cycle time. I'm not sure which version Sea Ray specified, but I'm assuming standard temperature and cycle times.

2. Preheat Cycle - If coolant is below 65* and ignition switch to RUN position, AH's come on for 30 seconds. Start the engine after the 30 seconds (or you see your volt gauge needle move back towards a normal reading). If you interrupt the AH cycle, the AH's are disabled. If you turn the ignition off, the cycle is reset.

3. Crank Cycle - AH's ON

4. Regular Heat Cycle - Once engines are started (oil pressure switch above 35 psi), the AH's run continuously for 5 minutes, then cycle ON (10 seconds)/OFF (10 seconds) for up to 15 mintes, until the the engine coolant/switch is above 85*, then turn off the AH's.

5. If engine coolant cools to below 65*, the coolant temperature switch resets and the AH cycle is reset. If the coolant temperature/switch stays above 85*, the AH's are disabled (not AH required).
 
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Actually found a Air Heater section in the CAT Manuals with a pretty good description, schematic and a Functional Flow Chart that lays it out in detail. Its about 5 pages long. PM me if you would like a copy of that section. What I wrote above is fairly acurate, the CAT documents have a little more detail if you were trying to troubleshoot.
 
dtfeld said:
Actually found a Air Heater section in the CAT Manuals with a pretty good description, schematic and a Functional Flow Chart that lays it out in detail. Its about 5 pages long. PM me if you would like a copy of that section. What I wrote above is fairly acurate, the CAT documents have a little more detail if you were trying to troubleshoot.
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Perfect, thanks. I’ll look at the service manual as well

I think that might why towards the end of the season I had a little bit of smoke on morning startups after being on the hook. I never let ignition sit on (and beeping) for the 30 seconds so I must have been interrupting the AH cycle.

next time I chase wires up to the helm I’m going to add some low voltage wire for an indicator LED on each engine. I would like to know when they’re heating
 
Strecker25 said:
Perfect, thanks. I’ll look at the service manual as well

I think that might why towards the end of the season I had a little bit of smoke on morning startups after being on the hook. I never let ignition sit on (and beeping) for the 30 seconds so I must have been interrupting the AH cycle.

next time I chase wires up to the helm I’m going to add some low voltage wire for an indicator LED on each engine. I would like to know when they’re heating
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I thought about running the wires, and adding an indicator, but to me it very obvious when they are on. The interesting thing I learned reading this this morning, is that if you interrupt the preheat cycle, it disables the AH's. I was considering a switch to turn them off for most of the year, but turns out that is unnecessary.

I think I'll keep the system as is...ie its already KISS!!
 
dtfeld said:
I thought about running the wires, and adding an indicator, but to me it very obvious when they are on. The interesting thing I learned reading this this morning, is that if you interrupt the preheat cycle, it disables the AH's. I was considering a switch to turn them off for most of the year, but turns out that is unnecessary.

I think I'll keep the system as is...ie its already KISS!!
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you’re probably right, I should just leave it. The voltage drop should be a good indicator pre-start
 
Cocktail Time said:
Just spoke to CAT and 3116's have a Crankcase Breather, no replaceable element change every 2000 hrs. https://shop.cat.com/en/usa-parts/filters/4W-3027 but, I appreciate the direction. I'll wait to swap that out. Now to see what model Walkers I have. Maybe they do have an element in them?
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I just bought 2 of these and there is no reason in the world that these can't be cleaned with solvent, dried out, and put back in...
https://gtengineparts.com/538857 $33.50 each
IMG_20210315_163930903.jpg
IMG_20210315_163943924_MP.jpg
 
Aftercoolers are coming off today, any helpful hints for draining the coolant without making a total mess?
 
Carver370 said:
Aftercoolers are coming off today, any helpful hints for draining the coolant without making a total mess?
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The 3116 is AF cooled, correct? Can you drain the coolant down past the aftercooler level? That should help

Ours are seawater cooled but I had winterized already before removing them so they had AF in there. I pulled the zincs to let them drain (there was very little left in there) then cut the hoses off with a razor blade because I was replacing them anyways.

I'd replace your turbo hose and clamps as well if it hasn't been done in a while
 
Strecker25 said:
The 3116 is AF cooled, correct? Can you drain the coolant down past the aftercooler level? That should help

Ours are seawater cooled but I had winterized already before removing them so they had AF in there. I pulled the zincs to let them drain (there was very little left in there) then cut the hoses off with a razor blade because I was replacing them anyways.

I'd replace your turbo hose and clamps as well if it hasn't been done in a while
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Yes these are AF cooled. I plan on just changing the coolant at the same time, all 14 gallons total.

I did buy all of the new hoses and gaskets already that you normally cant get to, great advice!
 
Slight mess of coolant but the aftercoolers are off. They definitely had some gunk built up in them.
4E525BE2-0629-44A8-962D-825F9B73498C.jpeg


Perfect time to steam clean the engines and bilges. Starboard engine is done already, port tomorrow.
 
Carver370 said:
Slight mess of coolant but the aftercoolers are off. They definitely had some gunk built up in them. View attachment 101380

Perfect time to steam clean the engines and bilges. Starboard engine is done already, port tomorrow.
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yes, another crazy steam cleaner! :)

how did it work to get the grease/grime off the engine? I didn’t try it yet as we’re still below freezing and I suspect I’ll get some water collecting in places

did you do the topsides of the engine as well? Looks nice and clean
 
Speaking of cleaning things up, I am going to touch up my gen and Cats. I have the red for the westerbeke, what is the paint code for the Cats?
 
Carver370 said:
Yes these are AF cooled. I plan on just changing the coolant at the same time, all 14 gallons total.

I did buy all of the new hoses and gaskets already that you normally cant get to, great advice!
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Smart move - the Cat coolant will leave a film on the engine internal surfaces if the coolant is old and hasn't been changed per the scheduled maintenance and inhibit the heat exchange that very coolant is supposed to do....
Make sure you flush the engines as well and then go back with Cat ELC.
 
Seymour at $7.00 a can vs cat @16.99 ?
I like how the Seymour covers.
I don’t see the zip tie your talking about?
 
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