[Nicholas]

I thought the same thing I just don’t see what it could be. The airseps are also only 2 years old and I don’t see any sign of deterioration or anything. Only thing I could think of would be…and this would be awful…maybe the techs when disassembling the engine for cooling system flush used the filter as a bucket to put nuts and bolts in…then maybe they forgot a washer or something in there when it went back on. I guess if so we’ll find it when we disassemble everything looking for the blade. 

[Nicholas]

Despite the fact that the turbo spun freely, upon closer look it threw a blade. Suspect the blade is downstream somewhere, maybe stuck in the charge air differential diaphragm or maybe in the intercooler. <br /><br />

In any case, the turbo is shot and didn’t realize it until a closer look with the airsep pipe removed.

crazy thing is the turbo is almost brand new – replaced in 2021, probably less than 100 hours ago, by the previous owner according to my documentation. Seems very odd for a blade on a new turbo to just break off. The tips of the other blades don’t look good either, although I attribute that to it being out of balance after throwing the blade. There is no perceptible wobble in the rotor that would suggest the blade was broke off due to a dynamic tip clearance issue. 

almost like something hit it, but that doesn’t make sense either because I’ve never run it with the airsep removed. 

[Nicholas]

No I have no boost pressure or EGT readings. I plan to add both. At this point, I know my boost pressure is zero or close to it because the turbos make a very audible whine, which I can hear on the port engine but not the starboard so it’s obvious the two on the starboard are not spinning up.

I agree with your instinct – I’ve had these exact symptoms a handful of times before on different engines and every singe time it was a busted hose clamp or split hose. But I’ve gone over them all and can’t find anything. Suppose one could be collapsing internally so will try replacing any that aren’t brand new (most are).  I was just trying to figure out if it was possibly something a little less obvious, like a waste gate stuck open or something like that, but I don’t understand how both turbos would be affected as it seems the only place they are connected to each other is on the exhaust side. Everything else seems independent. 

[Nicholas]

I was able to source a used OEM cooler. Appreciate the offer to help, may take you up on it when the other one inevitably goes bad 😉

[Nicholas]

Heck you’re practically next door! Enjoy the vacation and appreciate the suggestion. I had asked around and didn’t find anyone willing/able to fabricate it. I do have the old cooler to send. Any sense of how much it would save me vs the $9k OEM option? <br /><br />

Happy to discuss on the phone but don’t want to bother you on vacation (any more than I already have)

[Nicholas]

Thanks for the recommendation on Dallas Coolers. Jerry has been great to work with. Unfortunately the cooler is shot. Failed the pressure test. He tried to fix it but said its just leaking in too many places. He said he doesn’t have/can’t make anything that matches it. 

Any other suggestions beyond just biting the bullet and ordering a $9k replacement from ZF? 

[Nicholas]

Thank you Tony!<br /><br />Question – how would the cooler oil inlet/outlet be connected? When I look at the parts diagram, it just shows rigid tubes on either end of the cooler extending to the gearbox with a single o-ring. I don’t think it’s a face seal because there doesn’t appear to be any sort of flange. (Pic of parts diagram attached)

also – do I need to drain the gearbox oil to remove the cooler or is the gearbox oil level likely below the cooler when it’s sitting unpressurized?

[Nicholas]

After a little searching, seems like its common for the o rings to go bad on the delivery valves, so I suspect that’s the culprit here.

[Nicholas]

Just wanted to report back on this. I decided to bite the bullet and drop the oil pan. In hindsight, I shouldn’t have spent so much time wringing my hands over it.

Removing the broken studs was simple and the oil pan itself was not heavy at all. I decided to replace the gasket as well, although I did not know to put any sort of RTV or gasket sealant on it, which I hope doesn’t bite me later.

If I had not been replacing the gasket, it probably could have been a 1-person job by installing longer threaded studs and lowering the oil pan only part of the way down. But because i had to get the gasket around the sump, I had to drop it all the way down, and thus needed a second set of hands to raise it back up evenly. I did put in temporary studs to help with alignment bringing it back up.

My wife ended up helping me…she is much better sized than me for working on the outboard side of the engine.

The hardest part was retorquing the bolts on the front and back of the oil pan where access is terrible. Never was able to get a torque wrench on them – had to install them by feel and tighten them with whatever combination of extensions and sockets and ratchet handles would fit.

Anyway, its now fixed and only leaks the “normal” amount now. 🙂

[Nicholas]

Ok thanks. I may see if I can get some help. Removing the coolers and trying an ez out seems like the best route, but I guess I run the risk of ruining the threads on the block if I get misaligned.

Dropping the oil pan seems “safest,” but is beyond my abilities.

[Nicholas]

(apologies if this is a duplicate post but my posting disappeared after i thought i posted it)

Decided to go ahead and try to tighten the oil pan bolts, and to my horror there were 6 missing bolts on the aftercooler side of the engine, all in a line from the aft most bolt to the middle of the pan.

2 of the bolts in the middle section were just plain missing – so I got some metric bolts from the h/w store and put them in.

The last 4 bolts all have sheared off heads. I found 2 sheared off heads in the bilge.

So, it appears I’ve been running for who knows how long with several missing oil pan bolts, and 2 more just let go, leading to the big leak.

Any suggestions of the best removal method for getting the 4 bolt studs out? They are all flush, or slightly recessed, so there is no way to grip them. It’s possible if I remove the aftercooler and fuel cooler, I could get a drill underneath the pan. But I’ll be holding the drill up side down and would have to drill them out blind, and the oil pan itself will probably interfere keeping the drill straight.

Has anyone done this before in this tight of a space and had success?

[Nicholas]

I THINK the oil pan seal is the most severe of several possible leaks. Its possible that oil is just collecting there from a leak above, but when I run the engine, I think I can actually see a little bit of oil oozing out of that seam, and after a long run yesterday, the near-by stringer and floor of the engine room was covered in a misting of oil. Only other thing i can think of is that i damaged a fitting or something above that area when I put the aftercooler back on after servicing it a few weeks ago.

Also, access to my oil fill isn’t great and I occasionally spill some oil when filling, which then finds its way down the side of the engine. So some of what you are seeing is from that. But, like i said, i also think i have more than one leak.

I will clean up the engine, run it a little more, try to find the other leaks and post some more pics, but I’m 99% sure this area is the severe leak responsible for the recent dramatic up tick in leak rate.

[Nicholas]

Here’s a photo if anyone is curious. Crazy to see the bracket sheer on half like that

[Nicholas]

Turns out it was easier than I thought to find parts. Was able to order a new bracket. Alternator is proving tougher but I just need to find the right kubota cross reference.

[Nicholas]

I only saw the spray cans – so I just alternated between spraying them down, rinsing them off, drying them out, and repeating. It was very time consuming. Soaking may have been a better bet.

The guy who runs one of the diesel shops here at my marina told me next time to just drop the cores off and he’d put them in his cleaning tank for me. I’ll probably take him up on that next time. I don’t feel like I got them as clean as I wanted to.

[Nicholas]

After 8 gallons of simple green and 11 cans of brake cleaner, i’m about ready to re-install the cores. Here are some things I would think about for next time:

-Even though the cores had been installed “the seaboard way” when delivered, the silicone strips made them hard to remove. I still had to hammer out the cores with blocks, and then pry them out the rest of the way. Hopefully with the strips removed now this will go much smoother next time

-I’m not sure how productive the overnight soaks in simple green were. I didn’t have much in the way of calcium or barnacle deposits – only soot on the air side that really needed cleaning. The simple green soaks didn’t have much affect on the soot.

-The best way to get the soot off seemed to be brake cleaner, pause, more brake cleaner, pause, spray with simple green (not necessarily soak in simple green bath), pause, hose off, repeat. I think i could have used my brake cleaner much more efficiently than what i was doing at the beginning, which was basically just spraying until i emptied the can, then grabbing another can and continuing to spray.

-The heavy greasing of the “seaboard way,” in conjunction with occasional freshwater flushes (whenever I knew it was going to sit for a while) and the somewhat lower salinity of the middle Chesapeake bay are a good combination. 2 1/2 years didn’t seem to have been an issue – so i think i’m safe to proceed on 3 year cycles moving forward.

1 user thanked author for this post.

John

[Nicholas]

Rob Schepis wrote:

Yes, for sure NO ONE cares about your boat as much as you do. Well maybe us! Use one of the bolts for dia and length and get new flange head bolts.

right that’s the plan. from my reading though, it seems like zinc coated flange bolts will actually cause less corrosion issues with the dissimilar metals (aluminum in particular) than stainless steel.

does that sound right? just use zinc bolts, not stainless in this application?

[Nicholas]

Apparently, when I had the coolers replaced, the tech who installed them must have lost a couple of the bolts that fasten the cooler to the lower bracket because one bolt was new stainless and the other was missing all together. So I need to do something about those at a minimum. (One of many examples of why I now go out of my way to do everything I can on my own)

The other mounting bolts have varying amounts of corrosion, but can probably be saved, albeit with whatever coating was on them originally certainly no longer present.

The cap bolts are fine – they are less than 3 years old.

[Nicholas]

Got it. Will grease the spots and leave it at that.

Any recommendation on replacement fasteners?

[Nicholas]

I don’t think it’s soot. I cleaned it all out already. It’s hard and smooth like paint.

[Author]

Replies