Cat 3116 Problem

M

micadk

New Member
Jul 27, 2007
18
Houston TX
Boat Info
1996 440 Express Bridge
Engines
Cat 3116 TA
Hey all, I have a problem I have been trying to figure out. It will be a long drawn out story, but I am trying to give as much info as possible.

Cat 3116 TA engines. Last fall I was taking a trip to Lake Charles. We left on the evening, and as I made the ship channel and hit the throttles, it started blowing black smoke and would not get up on plane.
I turned back, and replaced Racors and the spin on filters. Left again and had no problems.
About half way there, I hit a small log in the water with the port prop. I was running about 14 knots, and got a pretty good vibration. I slowed down to 10 knots, the vibration was not noticeable, and we continued the trip. I checked the running gear when we got there, and no big problems, nothing that was evident, so we drove back at 10 knots. This trip is 150 miles one way.
When back I had the prop pulled, and scanned. The fixed one blade, and re-pitched it. You could not tell by looking at it there was anything wrong.
Put the prop back on and went out. The boat would not get on plane, and has a lot of black smoke. I changed fuel filters again, and air filters. Had the boat pulled and cleaned the bottom. I can't figure out what is happening. It seems like a fuel issue. Both engines are smoking, and neither will get more than 1950 RPM. I don't hear the turbos spool up on either engine. Tried each engine by itself, or together there does not seem to be any difference.
 
Have you had the top end reset ever? Basically valve lash adjustment... Not sure if that would cause this problem but it is a maintenance item that needs attention at certain intervals.
 
I have not had the top end adjusted since I have owned the boat. There were 350 hours on it when I bought it 4 years ago, now at 700. Another guy I talked to about this problem also suggested this. I am unsure that this is the problem because this happened rather suddenly to both engines at the same time. If that were the issue, I would think that it would happen to one or the other engine, and would give some issues/symptoms for a while. But I do not know, that could be it. That is why I am asking.
Thanks for the suggestion.
 
That is what I am thinking, fuel issue. But I don't know. The Racors had some algae looking stuff, but no water. I burned through over 600 gallons last year, so the fuel has not been sitting around.
It looks as though I need to have the valves adjusted anyway if it is a maintenance item, so I will probably get that set up to do.
 
I'm no Frank Webster (but I know him and have slept in a Holiday Inn Express before) - are you complying with the CAT Bulletin on SAEO (Special Application Engine Oil)? Marine 3116's and 3126's must run on straight grade oil - not multi-viscosity oils - due to crankcase ventilation issues. The crankcase vents through the turbo and aftercooler and the viscosity enhancers of multi-viscosity oils clog the aftercoolers - wehich will make black smoke. If you have been running multi-vis oils, you may have clogged your aftercoolers.
 
From the original post, this seems like a rapid onset problem. I'm not trying to state the obvious here, but that is where to start......a fouled bottom or shafts and props will certainly cause excessive smoke with a rapid onset and prevent the boat from breaking over on plane.

The cause for the turbos not spooling up can also be narrowed down by the process of elimination with the rapid onset symptom.

1.Striking an obstruction would cause the vibration in the running gear and may cause sooting over a long run at low speeds, but not a bunch of smoke all at once and the boat should still spool up and turn rated RPMS.
2. Clogged fuel filters......nope- they cause fuel starvation and excessive smoke is unburned (too much fuel).
3. The aftercooler clogging does casue air starvation and will cause some sooting on the transmo....but not a lot of smoke when the throttle is advanced.

Both engines with the same symptom also kind of eliminates the turbo or turbo control system. SOmething is preventing the engines from developing enough pressure to open t he turbos.........points toward a fouled bottom.

Lastly, if you don't have service records showing that your engine overheads were reset at the prescribed 250 hours after rebuild, then you should have it done. The overhead service adjusts the valves as well as injector timing and dwell and it is important on a new rebuild, but would not cause the engines to fail to spool up or cause them to emit a lot of black smoke.

I don't usually do "it isn't this that or the other" answers and prefer positive suggestions pointing at solutions, so I'm sorry I can only come up with one idea that is a most likely cause............but the good news is that it is the cheapest fix of them all.
 
Pull a fuel sample and have it inspected. One possible cause is an algae bloom. Happened to me a couple of years ago. Not sure about the black smoke, however I experienced a noticeable loss of power and had difficulty getting on plane. It seemed like a rapid onset issue at the time. Algae in the Racors is certainly a sign...

it it was a pain to have to deal with - had the fuel polished, however it took a while to fully resolve the issue.

Paul
 
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Thanks Frank, and everybody else. Like I stated before, I pulled the boat and cleaned the bottom, when this began, which was not bad. It did come on rapidly and seems to affect both engines which leads me to fuel. I have thought about fuel polishing. I will also set up the overhead service as i do not know if it has ever been done, but I do not think that is my issue.
What is the turbo control system and what opens up the turbos?
 
So pulled it out of the water and had one of the propellers worked then put the boat back in the water and had issues with both engines. Both engines sooting badly and cannot obtain RPM or get the boat on plane - right?

Can both the prop shafts be rotated smoothly by hand? ie; if the shafts are bound up for some reason and the engines cannot turn them, you will get fuel with throttle settings but the engines will not spool the turbos creating all of the symptoms you are seeing.

Were you there when the boat was pulled? Eliminating something the yard workers might have done like lift straps around the drive train or bending the struts......
 
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Actually ttmott, I had the problem with the prop, and had it pulled by a diver. Took it to the shop and had it scanned/repaired, and the diver put it back on. Then took the boat out to check it and it would not run up on plane. Then started with changing fuel filters. No difference. I pulled the boat out of the water at this time to check it out. I was there with the boat when it was pulled, and both shafts will spin freely, I put new shaft zincs on when it was out. Then I changed all the fuel filters again, Racors and spin on, and added some fresh fuel just because.
That was good catch though.
 
Well I would defer to Frank, but you haven't mentioned checking the turbos.

If you had a problem with wear or excessive oil in the turbos, they might not spool up. I would remove the air filters and inspect the turbos. I'd also inspect and clean the breathers. Sounds like you put these engines under pretty heavy load without the turbos spinning and heating up the engines. Are you seeing excessive oil on the air-seps?
 
Thanks I will check the breathers. And I can take the filters off and look at the turbos, I don't know what I am looking for really though. I guess anything that looks bad, LOL. I have not really loaded the engines much, and no heating. Just normal temps. I have not run very far since this has been going on. I am not seeing anything abnormal as far as oil on the air filters. There is not much there.
 
Ok I am at the boat, so here is an update. Took the air cleaner off the starboard engine and looked in at the turbo. I cant tell anything but it looks ok. I cant reach the fins to spin them, and i dont want to stick anything in there. I started the engine and looked in from the air cleaner and the fins are not spinning. I ran the rpms up and I can get 2300 but i do not hear the turbo spool up. There seems to be a rattling sound coming from in between the two housings on the turbo. That isnt good is it?
I started the port side and ran the rpms up to 2300, no sound from the turbo spooling. When do they start whistling normally?
How difficult of a job to replace the turbo? It does not look that difficult, but I dont know if there is any tuning or adjusting involved. I guess i will have to call Elite Diesel and have them come out.
 
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