6BTA Spool Up Issue

[siwicki]

Dear Tony,

Carolina Classic 28 with a pair of 6BTA5.9 M3 330HP. Roughly 2200 hours on the engines with no major problems. Cummins did a full service at 2000 hours which included adjusting the values. I generally put about 60-80 hours a year on the engines. I also have your water pumps on for the last three years.

I had a strange problem with my starboard engine that happened on my last trip in December, the afternoon before I had to haul and winterize for the season. I am hoping you can give me some ideas where to start in a few weeks as I prep for launch.

The bottom line is the starboard engine seems to be operating fine at idle and troll, but the turbo won’t spin up and it smokes like hell when I try to take off. So let me explain the day as this quickly progressed to give you some background.

It was about 35 degrees when we fired up at the slip(Cape May, NJ). I have Wolverine oil pan pads on year round so there is generally no issue with a smooth start even when the temp is in the upper 20s. This particular morning, the starboard was a bit difficult to start. I normally pump the throttles twice and then set just above idle for starting after the ignition has been on about 8 seconds. The Port fired right up with no problems and the starboard took a few tries and I had to add more throttle advance before it lighted up. Seemed to be running fine, so I figured maybe it was just the cooler weather since I hadn’t run the boat for a few weeks. We took off and ran about 10 miles to our first trolling spot. Both engines spun up fine with no smoke, just a little steam as is normal when it is cooler. We hopped around several runs like this trying to find the fish and were now about 30 miles north.

The next time when I when to throttle up, was the first sign of an issue. The starboard lagged pretty bad when the turbo should have kicked in. I think it only spun up because the port engine turbo engaged and probably pulled the starboard up after about 20 seconds. This was usual for my boat because typically the starboard turbo usually kicks in about 5 -10 seconds before the port. Still everything seemed to be running fine for a while and then I started getting dark gray smoke out the starboard exhaust. The attached video captures what it looked like. All the gauges were fine and both temp and oil pressure were reading normal. I throttled back and the smoke stopped. I tired to take off again and the starboard turbo just wouldn’t engage this time and we had a lot of black smoke.

I brought the boat to a stop, put her in neutral and raised the engine hatch. Two things immediately popped out at me. I had oil sprayed on the inside rear of the engine and I had water dripping onto the transmission.

The oil was a result of the puke bottle I had attached to the crankcase blowby hose filling with oil and the blowing out the hole in the cap where the hose loosely entered the bottle (pictures attached). This is unusual for me since there is hardly ever a drop of oil in that bottle on either engine over the course of a whole season.

The water was a result of a small hole in a raw water system pipe. It is a metal pipe that is connected to out bound side of the gear cooler by an elbow rubber hose that turns downward. The pipe runs under the turbo and then connect via another elbow rubber hose (turned upwards) to the bottom of the heat exchanger(picture attached as well). I don’t think the water leak has anything to do with the engine issue. I think it was leaking for a while since I had noticed my bilge would briefly kick on a few times during the last couple of trips. I had checked but couldn’t find any leaks. This was hidden pretty good since it was between the turbo and the transmission. Multiple calls to CUMMINS and they have yet to identify the pipe so I can order replacement.

So at this point I shut down the engine and we made the 12 mile journey back to the dock on one engine at trolling speed. Got back to the dock, took some pictures, cleaned up the oil, and then removed and patched the leaking pipe. Got up the next morning and tried to take a quick ride before haul out. The engines started fine, but the starboard wouldn’t spin up and smoked when I accelerated. I had no choice but to haul out and winterize the engines for the winter nap.

I spoke to a diesel mechanic friend who has worked on my engines in the past before he moved to Florida. He didn’t think it was the turbo, but maybe a fuel filter or an injector issue.

Aftercoolers, gear coolers and heat exchangers all removed and fully serviced per your protocols about 180 hours ago. Already have your kit with planned service before launching next month

The fuel filters get changed every spring

The injectors are all originals to the best of my knowledge.
Removed Air filter. Turbo spins free, feels tight and no binding.
No sign of water spray on the filter, only dripping down onto the transmission. Using S&B filters, clean and treat every spring. Filter is still clean inside and no oil in the air side of the turbo.

No signs of any broken clamps or leaks related to turbo, but will have to look harder when I get to the boat in a couple of weeks. Boat is docked 4 hours from home. No whistle noise or change in normal sounds other than not spinning up.

From the time I left the dock to the issue starting was about 4 hours. Engines were running continuously either cruising or trolling. I would appreciate any advice on what you think it might be and where to start.

The most recent picture of the exhaust side is shot of the engine compartment about a year ago before I cleaned up and repainted the coolant tank and the exhaust side of the turbo. The one with the fresher paint job is after a cooler service and painting in 2011, but shows the elbow better

Thanks

Steve

Topic

[Tony Athens]

Just what I suspected early on…….This engine has been on a salt water diet for years.. #5 & #6 cylinders always go first when it’s an inline drive. When you pull the head, drop the valves on 5 & 6.. You’ll see it big time on the stems and seats.

As to all the rest-No sense fixing the damage until you fix the “reason” why it happened–It’s called Poor Exhaust design & not following both Cummins & common sense requirements..

Tony

[siwicki]

Mechanic prepared the engine for removal tomorrow. Ended up having to cut the last two bolts on the turbo exhaust. Pictures attached.

[Tony Athens]

I suspect we may all “discover something” inside related to your issues..

Pics need to be clear & in-focus from about 18″ away and then from about 10″ away.

Tony

https://www.sbmar.com/articles/what-a-marine-diesel-turbo-should-look-like-when-inspected/

https://www.sbmar.com/articles/new-turbo-vs-27000-hours-turbo/

[siwicki]

Tony,
Still working the turbo bolts. I am about ready to put a chisel to the three remaining bolts. Been doing heat, PB, and tapping with no luck. Back at it again tomorrow.

[Tony Athens]

When do I get to “SEE”inside the turbo/exhaust outlet?

Tony

[siwicki]

Insurance is paying for discovery for now. Mechanic did pressure test. Cylinders 6 and 5 have zero compression. 1-4 were good. Definitely blown head gasket. Given the oil blow by at the time of the incident, mechanic believes it is probably a piston ring. Going to start the process of pulling the engine for a tear down to get to the bottom of it.

Any thoughts welcome.

[siwicki]

Waiting for the insurance adjuster to visit the boat to see if it is covered or I am tackling this one with a friend. Any opinions on the current diagnosis other than a blown head gasket?

[siwicki]

Tony,
Yes, external fuel solenoid was pulling the run lever to the full up position when cranking.

My former mechanic was passing through NJ and met me at the boat today. We opened and verified fuel was pumping to all the lines. Used the correct tool to expose the cams in the housing and verified they were all functioning. Verified we didn’t have a stuck rocker.

Pulled the value covers to verify we didn’t have a dropped valve. The valves all seemed to be functioning normally, but we could hear an air rush in a regular interval when turning it over.

Mechanic suspected a blown head gasket. We uncapped the radiator cap and it was pressurized quite a bit despite being cold. Cleaned up the coolant that spilled out and gave the engine a crank. There was a regular interval gurgle of air bubbling out of the top of the tank when cranking.

Next we removed the hose connection at the air exit of the after cooler. When had the hose off and cranked for 30 seconds, when we stopped, we got a small amount of exhaust smoke coming back out of the hose about 20 seconds after we stopped cranking.

Mechanic friend is convinced between the air bubbling in the coolant and the exhaust smoke pushing back out to the air intake side that I have a blown head gasket.

Before we go through the effort to disassemble and replace the head gasket, do you agree with the diagnosis?

[siwicki]

Tony
I still have the arm zip tied to full power. I have the solenoid plugged in but just hanging. I will be able to check that tomorrow.
thanks
Steve

[Tony Athens]

Fuel solenoid

While cranking, is the external fuel solenoid pulling the run lever to the full UP POSITION or “sucked up” position .

Tony

[siwicki]

Tony

Tried 5 times per you note and it didn’t start.

At the end of each 30 SEC attempt, the plunger was hissing. Sounded like it was also hissing while cranking but tough to be sure.

No change in the turn over sound.

Had a friend with me that has 4b and 6b engines in his construction equipment and he agreed it sounds like the engine is not getting fuel.

[siwicki]

Thanks Tony, Will try that this weekend when I am back at the boat.

[Tony Athens]

“While the lines were disconnected from the injectors, I pushed the fuel pump primer. It didn’t push out any more fuel and hissed after 3-4 pumps.

Reconnected the fuel lines and cranked the engine. The first 3 seconds, the turn over sounded normal, then it went back to a groaning kind of sound. Still did not fire up or seem like it might.”

“Hissing”–“SQUEAKING” is good..

Open the throttle 100% to WOT.. Pump away & crank—- Be sure the battery is good and crank for 30 second intervals..The wait for 2-3 minutes..

Fuel will not come out the injector line while pumping and “squeaking”…………

Tony

[siwicki]

All,
Just back from an expected 3 week trip to Afghanistan. The boat is now in the water. Still working on the turbo exhaust bolts. Got one bolt off so far. Hopefully another period coated in PB Blaster will loosen the other ones. In the mean time, new after cooler core and new gear cooler installed. New water pipe below turbo (between gear cooler and heat exchanger) installed.

Only problem, this engine (starboard) won’t start, which I believe is totally unrelated to the spool up issue. Never encountered this problem in any of the previous spring start ups. Port engine fired up fine in less than 3 seconds. I have a recording of the sound on my iphone but this forum won’t accept the file for upload. Engine turns over but sounds like it isn’t getting fuel, sort of like a groaning sound as it turns over. Fuel Solenoid is still off and the arm is zip tied in the full position. Pumped the throttles numerous times and even tried starting with throttle in the middle and then WOT. Verified the throttle was advancing on the engine when pushed. Tried pumping the ball on top of primary racor filter and worked the primer on the fuel pump. The primer on the fuel pump starts to hiss after 3-4 pumps which I think means the lines are pressurized. Tried to start with no luck.

Next I opened each fuel line connection at each injector and turned it over for a few seconds. Got fuel in all lines but not as much as I would expect(first time doing this). Enough fuel to soak a small folded paper towel square between each of the lines and the injectors after turning over about 3-4 seconds.

While the lines were disconnected from the injectors, I pushed the fuel pump primer. It didn’t push out any more fuel and hissed after 3-4 pumps.

Reconnected the fuel lines and cranked the engine. The first 3 seconds, the turn over sounded normal, then it went back to a groaning kind of sound. Still did not fire up or seem like it might.

Headed back to the boat late this weekend.

Would appreciate any ideas to get the engine to fire up.

[Tony Athens]

6 point x 10 mm box end wrench. PB Blaster or Kroil and then heat.. It needs to come off..

Tony

[siwicki]

Thanks for the quick responses. I think most of what was removed was surface build up, but I will check that closely. I expect you are right and the core will fail the pressure test. Hope to have that done locally this week.

Turbo elbow is next when I get back to the boat the weekend after this one. I wire brushed off all the paint and loose rust. I couldn’t budge any of the bolts on the turbo elbow last trip despite multiple attempts with PB, CRC freeze, etc. Looking at heat and possibly bolt extracting wrenches. I am open to any other suggestions.

[Rob Schepis]

Ends look good. As to the 30mil Tony references, that’s about a credit card thickness…

[Tony Athens]

If the sealing surface looks like this on both ends, you are 100% as long as you did not remove more than .030″ to get it this clean/smooth.. The inner corrosion does not affect the sealing. If you did have to remove more, then you need to remove about the same for the core end.. When pre-assembled with no o-rings, the core needs to float in-between the end caps at least .020″ ~.040″ or up to about 1 mm….. If you end up buying new cores but not housings, then check the end clearance before you do final assembly…. This is all easy stuff to deal with. You just have to understand the logic and how it all is supposed to work…No “book” or manual will tell you that.

NEXT: Let’s get the exhaust elbows off the turbos for a good look inside..

https://www.sbmar.com/articles/what-a-marine-diesel-turbo-should-look-like-when-inspected/

Tony

[siwicki]

So I talked with Tony late Thursday and followed his instructions to block sand the cooler housing surfaces to see if they would likely seal. Photos attached and it all looks clean for the sealing surface. Trying to find a local shop to bead blast the inside corrosion per Tony’s instructions and to pressure test the cooler core.

Any opinions on the sealing surface?

[Mike Mason]

Those don’t look good. That’s a critical spot with the o ring. May be time for new housings and inserts.

Looks like your seeing salt on the air side as well. For sure indicates a leak. The cores may pressure test and your leak may be at the o ring.

CC, like many boat builders went cheap on the exhaust design. This is exactly why you have non original turbos in the boat.

Friend of mine has the same boat with similar problems and had Tony make him a set of custom risers to correct the issue. He had yanmars.

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siwicki

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