3116's smoking- where to start?

Guys, I am new to diesels and have an issue with black smoke when running at speed as well as with my genset. I did not notice this previously but I had a dock neighbor running behind me that said it was pretty bad. I recently had an algae issue in my fuel which I treated per Frank W's fuel system treatment post. Probably need another round of diesel 911 or whatever the fuel treatment stuff was and cleaning/changing out my racor's again. That said it is probably time to have my valves adjusted and I have no idea what that should run. Can anyone give me a ballpark cost on the following? and what the service interval should be? I have no idea when this was last done:
Valve adjustment for CAT 3116
Valve adjustment for Westerbeke 7.6BTD
Injector service/adjustment for 3116
Injector service/adjustment for 7.6BTD

Anything else to look at? Freshwater, clean bottom, straight shafts and props are good.

I'm not a Cat guy, but how are your air filters/air-seps? If it is starved for air, it will make black smoke.

Jaybeaux

Also, you need to be running the CAT oil for these engines. That will also help.

Cocktail


I'm going to be up at the lake the next couple days if you want a second set of eyes on it. Be glad to help. Hopefully something simple. Yancy Bros. is the local cat dealer. I've had good luck with them for basic filters/lube etc.


Black Smoke - this is the most common one and is really just an imbalance in the air to fuel ratio - too much fuel to not enough air. This means either too much fuel is being added to the mix or there's not enough oxygen being supplied to burn the fuel. The black smoke is full of particulates that are basically large diesel particles that normally would be burned as fuel. Any way you look at it, a diesel truck emitting black smoke is not going to be getting the optimal fuel mileage it should be getting.

Most common causes of black smoke are faulty injectors, a faulty injector pump, a bad air filter (causing not enough oxygen to be supplied), a bad EGR valve (causing the valves to clog) or even a bad turbocharger. Some of these are easy fixes.


Address: 330 Lee Industrial Blvd, Austell, GA 30168
Hours:
Closed ⋅ Opens 7:30AM Mon
Phone: (770) 941-2300

Air filters/separaters. Turbo after cooler may need cleaning. If the previous owner used a multi viscosity oil, it is very possible they may need cleaning. These are the first places I would look. Cheapest and DIY.
I'm sure Frank will chime in here and drop a serious knowledge bomb on us.

On 3116's the cause of excessive black soot/smoke is unburned fuel in the combustion process. There are several possible causes for unburned fuel......

1. an injector tip fouled with carbon or some other debris
2. restricted intake air flow from
a.dirty air filter
b. dirty or fouled aftercooler

Unlikely causes are using the wrong oil.... but it takes 1000-1500 hours to foul an afteercooler; bad EGR valve.....Cat 3116's don't have them; faulty injector pump....Cat pumps on 3116's supply constant high pressure fuel to the fuel gallery unlike other diesels that use a pressure distribution pump with bursts of pressure to injectors. If a Cat pump has a problem, the engine usually just dies. And, you have eliminated the usual culprits from the equation by stating you know the bottom is clean, and props are ok.

But here are some questions for you:

1. Did this problem just begin after you treated the fuel or was it present when you discovered sludge in the fuel system?

2. When you state the bottom is clean, are you assuming that because you are in freshwater? The 400DA is susceptible to performance problems with any excess drag on the hull. Freshwater algae can cause enough drag to cause sooting.

3. Do the engines turn up 2800 rpm? If not, the props may be too aggressive for the load on the boat and the engines will smoke.


Answers to your questions re: maintenace interval and cost:

The engine overheads (resetting the valve lash and injector timing) are supposed to be reset at 250 hours then not again until 2000 hours. Do both anytime the valve covers are removed because nobody other than a trained Cat mechanic with the correct gauges and tools needs to be messing with anything under the valve covers. So, if you are already paying a mechanic to come to the boat, you have paid a good portion of the cost just getting the mechanic there. So do the complete overheads if he removes the valve covers.

The cost is about $1200

Cat injectors do not need reqular service.....only when something is wrong.

Westerbeke:

I have forgotten the service interval (500-750 hours?), it is in your generator's operation manual, but you should periodically adjust the valves and re-torque the head bolts. It is a good idea to remove the Westerbeke injectors and have them sent to a diesel repair serivce to be pop-tested to be sure they open at the right pressure and stay closed without leaking. This test is done with a solvent that cleans the injectors while the test is done. If the test ok, then the cost is about $100, if not, the diesel service can rebuild them while they are there. That cost depends on what needs to be done, but these are small and simple injectors and the cost won't be prohibitive.



Recommendations:

If you are using multiviscosity oil, change to either Rotella T1 or Delo 400 or a similar single viscosity diesel oil, SAE 30 or 40 or Cat SAEO Special Application Engine Oil) at the next oil change.

If you are over 1000 hours have your aftercoolers removed and cleaned. Yours are jacket cooled so you don't need them cleaned by a radiator shop....a parts washer at the mechanic's shop is adequate. If you do this, order and replace all the hoses and hose clamps conected to the aftercoolers ( I have a list by part number for Cat replacement parts if you need it)

Try running another dose of Diesel 9-1-1 thru the system. I am leaning toward the fuel system being run too long with sludge in it since the engine and the generator were both involved.

Turbocharges may also be a problem if they are not spooling up. This isn't an owner's job because it takes gauges to test the turbo charger operation.

You may end up having to get Cat to the boat to evaluate the fuel system.

I hope that helps...........

Though, with the turbos you should be able to free spin them by hand.

Frank hit on this as well but I don’t know when this problem started or how long you have owned the boat. I will attest that most Searay boats are overpropped once fuel, water and belongings are added. Make sure you can reach 2800 rpm wot before you mess around with 30 other things. Also, and Frank mentioned this, black sample is I burned fuel, that’s it so keep that in mind when all the guys at the dock give you their opinion and story.

Frank hit on this as well but I don’t know when this problem started or how long you have owned the boat. I will attest that most Searay boats are overpropped once fuel, water and belongings are added. Make sure you can reach 2800 rpm wot before you mess around with 30 other things. Also, and Frank mentioned this, black smoke is Unburned fuel, that’s it so keep that in mind when all the guys at the dock give you their opinion and story.

Frank hit on this as well but I don’t know when this problem started or how long you have owned the boat. I will attest that most Searay boats are overpropped once fuel, water and belongings are added. Make sure you can reach 2800 rpm wot before you mess around with 30 other things. Also, and Frank mentioned this, black smoke is Unburned fuel, that’s it so keep that in mind when all the guys at the dock give you their opinion and story.

Awesome, thank you all. I am also leaning toward a fuel issue as it is only apparent at higher rpm's and with the genset. Using Rotella T and did a filters and fluids about 75 hours ago. Turbos sound and feel normal. I haven't gone past about 2400 rpm but will wind her up and see if she hits 2800. Like I said when I am cruising at 2400 rpm I don't notice a lot of smoke but apparently you can see it from the side and behind me. My transom has sooting and it is more pronounced on the starboard side by the genset exhaust. Will do the racors and another Diesel 9-1-1 treatment and see. Appreciate the advice and will report back on the cause and what corrected it, hell it might be normal and I am just crazy. Frank, I am at 1750 hours so the aftercoolers are on the list for this winter. Please let me know parts info you recommend.

Can you send me an email address by PM?