Engine smoke

[STB]

Hey Linda,

Thanks! Once the photo(s) are posted, I, I'm sure among others, wilk let you know what I think I see.

I'm Greg, btw. Hardly a guru. There must be social promotion over here!

 

[hfmckevitt]

Hi I’m Henry, the boat is named after my wife (Linda Lee)

 

[FF]

"Engine runs around 120 deg."

Smoke is common with an engine running that cold.

Install a working thermostat , so you operate closer to 180F.

 

[Ski in NC]

Yep, something wrong with temp regulators (Cat speak for thermostats) if it is running 120F.

Troubleshooting smoke is tricky. Can be many causes. And in some situations smoke (or it could be steam) is sort of normal.

Go into detail about the conditions where you see the smoke and when you do not.

Cold start both engines and let idle at normal rpm (usually 600-700rpm). Go look at the exhaust on both. Compare smoke.

With engines still cool, rev both up to like 1500. Check on smoke. Heavy smoke then on one could be late injection timing.

Back down to dead idle, go in engine room and pull the blowby hose out of the hole in air filter box (right bank), prop it up on top of box, and shine a light on the flow coming out. The will be a light flow of mist coming out. Looking here for a rhythmic "puffing" in sync with one cylinder firing. Puffing means bad ring sealing on one hole. Compare to other engine.

Get boat under way and put engines under a good load (like 2000) and IR gun the bronze nozzle where sea water goes into the exhaust mixing elbow. Compare to other engine. If one engine is like 10-20F hotter there, you have reduced sea water flow and that will make steam out the exhaust.

A few very cheap things to try.

 

[STB]

Hi Henry,

Note Ski's email...a very good point about using an IR thermometer. They are about $20 at harbor freight or Amazon and a little more at Home Depot or Lowe's. Get block and exhaust.

I dont believe gauges at all until proven and unless periodically reproven.

Get the temperature of both exhaust and block. I dont believe the 120 number. I sort of just mentally discounted it but probably shoukdnt have, but at least commented.

The particulars you are describing, worsening without lightening in color under load after use, doesnt sound like a cold block to me.

Im betting when we see it, it is a little blue grey with oil from turbos or a little loss of oil control or compression secondary to the overheating.

The only thing bothering me about the oil idea is 1 quart per 50hrs, while high for the engine isn't terrible if that 50hrs is ~25 gal of fuel and likely not enough to fully explain what I understand you are seeing.But add it to a small loss of compression or loss of turbo boost at 2000 and maybe.

 

[hfmckevitt]

Thanks,
After following Ski’s recommendations I will get back to you.

 

[Jimintheair3]

First of all you have the dogs gonads of an engine. Probably one their of their best
OK move on, somewhere in there is a HUMAN error, all diesel engines smoke until they achieve working temperature under loads. That's a fact !
Then its simply methodical.
So, lets get things in perspective.
Before those tree huggers in Europe triggered of this 'green' crap, diesel engines started and smoked a little until they attained working temperature after which they work hard ALL DAY EVERY DAY with no smoke unless badly maintained.
The newer diesels with computerised engines (I have one in my Mercedes E 320) work great with their particulate filters etc but then cruising down the high way the particulate filters cleans itself in somebody back yard WTF ?

The 'greens' in Europe have destroyed the car industry in pursuit of their ever green agenda.
By all means reduce pollution but with well researched un-unbiased thinking.
p.s Growing up on our farm we had no refuse collection service, we didn't need it,
We recycled everything and now the young tell us we should be recycling ! Wake up and smell the coffee.

Thank you for the "Rant", very helpful to OP.

 

[Vinny]

Most of the times that I have had injector problems they start out as a minor miss every now with a puff of smoke and then progressed to a more serious problem like dropping under load, and light to heavy smoke.

How’s your oil look and smell? Does it look normal or thinned? Does it smell of strong fuel? I usually start getting unburned fuel in the oil as a tell-tale to look for from my past experiences.

I’ve had a turbo go bad on a John Deere and give me boost problems before... that smoked light gray but like a sky writer and wouldn’t run under a load... smoked so thick that it muted out the sound of the muffler.

Cracked a valve on a DD V16-71 before that smoked light, ran fine under load, but I could hear a tinging/pinging sound through the stack when I got on the throttles.

I’ve had what I thought was light smoke from the stack on a Cummins that was really steaming from the stack, along with milky oil, wet on the inside of valve covers, water in oil pan, steaming out of the dipstick tube. That ended up being pitting around o-rings on my liners.

I’ve had stuck thermostats in a Amot thermostatic valve that made an EMD engine smoke bad, but engine would only warm up to 120 degrees.

Lots to narrow down, but you’ll find it.

And yes, diesels just simply smoke.

 

[hfmckevitt]

As of this morning I had the original mechanics that did a lot of work on the engines here. They now believe it maybe the injector time.
They plan on coming back next with the crew and run some testing at the dock and underway.
I will follow up with the results

Thank you

 

[Parro]

A Fact?

I have 5 (five) Detroit V71’s and none of them smoke at all on startup. Or when running under load or any othe time for that matter.
Sometime I wish they would so I could see it when starting from the bridge but no, it is not by any means a Fact.

Having said that I do see a lot of smoky diesel exhausts on the water.

First of all you have the dogs gonads of an engine. Probably one their of their best
OK move on, somewhere in there is a HUMAN error, all diesel engines smoke until they achieve working temperature under loads. That's a fact !
Then its simply methodical.
So, lets get things in perspective.
Before those tree huggers in Europe triggered of this 'green' crap, diesel engines started and smoked a little until they attained working temperature after which they work hard ALL DAY EVERY DAY with no smoke unless badly maintained.
The newer diesels with computerised engines (I have one in my Mercedes E 320) work great with their particulate filters etc but then cruising down the high way the particulate filters cleans itself in somebody back yard WTF ?

The 'greens' in Europe have destroyed the car industry in pursuit of their ever green agenda.
By all means reduce pollution but with well researched un-unbiased thinking.
p.s Growing up on our farm we had no refuse collection service, we didn't need it,
We recycled everything and now the young tell us we should be recycling ! Wake up and smell the coffee.

 

[Slider70]

Most 3208 engines either start instantly or don't start at all. The last one I owed only smoked after trolling for 10 or 12 hours or running at idle all night running my freezer compressor. And then only for less than a minute once taken up to cruising speed - I ran at 1800 rpm.

 

[EngNate]

That engine should produce no visible smoke once operating temp is reached, and very little otherwise after 2-3 min from startup. Good advice has been given, but I don't remember seeing fuel filters mentioned, restricted fuel causes smoking; also check that the return line isn't blocked; be sure it isn't steam from insufficient water flow; check that the turbo spins freely; at that point check the injection timing - the drive gear on the injection pump is a taper fit without a key - it can slip. This isn't hard to do, there is info on the web with pics somewhere. After that, pull the injectors and have a look at each one to possibly identify a cylinder with a mechanical issue and follow up on that. When that is put back together check the valve adjustments. After going that far without a cause & solution I'd be pulling the injection pump and sending it in.

A qt/lt of oil for 50 hours is within the normal range for that engine, but do a check to see if you might be keeping the level too high. Check level after 50 hours and put a small mark on the stick with a file or scribe, do not add oil. Check after another 50 and make another mark then compare the two. If it uses less oil at a lower level, keep it there.

 

[Lepke]

So, lets get things in perspective.
Before those tree huggers in Europe triggered of this 'green' crap, diesel engines started and smoked a little until they attained working temperature after which they work hard ALL DAY EVERY DAY with no smoke unless badly maintained.
The newer diesels with computerised engines (I have one in my Mercedes E 320) work great with their particulate filters etc but then cruising down the high way the particulate filters cleans itself in somebody back yard WTF ?

The 'greens' in Europe have destroyed the car industry in pursuit of their ever green agenda.

p.s Growing up on our farm we had no refuse collection service, we didn't need it, We recycled everything and now the young tell us we should be recycling ! Wake up and smell the coffee.

ditto, except the electronic engines are only as reliable as their sensors. And on this side of the ocean it's the EPA that screwed everything up.

If we could all just ride bicycles and eat shrubbery the world would be perfect.