White smoke in E38 Universal diesel engine

[Christian Williams]

Marie,

Well, maybe your video shows steam. If true, that's better than smoke. (Actually, as a result apparently of temporary site migration issues, your video now displays not either, but instead my friend Olivia Wyatt in a music video--at least on my computer).

I have steam in the exhaust ,too. Also, not as much water burping out of the exhaust as expected. That prompted me this week to rip out my entire cooling system to replace all hoses and revise the heat exchanger/water heater path. Overkill, no doubt.

As Bob says, often steam is result of not enough raw water entering the exhaust system. That may just mean servicing the heat exchanger, or finding some other constriction in the raw-water cooling circuit.

I'll report next week on whether my steam is reduced by a clean heat exchanger.

Oh, and your rpm is lower than expected*, even with a 3-blade (*if you have the typical Universal 5432; mine runs at 2300-2500 cruising, Wide Open Throttle is 2800). Often tachometers are incorrectly calibrated. If you can make the expected 6-7 knots, that might be it. At only 1700 rpms I'd be making about 5 knots with my 3-blade Michigan prop.

 

[Baslin]

Marie,

Your prop may be oversized or the pitch is off. Might want to check if the prop has been replaced at some point or possible bent.

 

[debonAir]

I'd expect top RPM to be a bit low when in gear and tied to the dock. The water is moving about 7kts slower past the prop than it would underway, but 1700 does seems low even there.

When was the last time your raw water pump was serviced (new impeller and clean raw water strainer at least)?

You probably have two coolant reservoirs. One that is connected with two sturdy hoses to the engine's fresh water pump and heat exchanger which is the regular one like you'd have in your car, and the other one would have a small hose to the exhaust manifold which is just an overflow tank for the manifold's coolant supply. I think the manifold can get hotter faster than the engine block and the expanding coolant needs a place to go before the thermostat opens and the main coolant tank would take it?

 

[Christian Williams]

Marie,

Here's my full report on steam in the exhaust. https://ericsonyachts.org/ie/threads/cooling-system-upgrade-2020.17240/

Also: The plastic jug is a coolant overflow container. It connects by a small rubber hose to a stub under the pressure cap on the engine. If coolant expands while the engine is running, it rises into the plastic jug. When the engine is shut off and the coolant cools, it gradually returns to the manifold tank on the engine.

I usually have very little coolant in the jug even when running.

 

[MCD]

Good news, we were able to take the boat out and make the compression test, and I think we can rule out any serious compression issue!
The rpm reached 2100-2200 full throttle, which is what we used to have if I remember correctly. And when opening the oil valve at the top of the engine while running, not oil splash.

My plan is to investigate the cooling next.

When was the last time your raw water pump was serviced (new impeller and clean raw water strainer at least)?

We had an issue with the raw water intake earlier this Fall. We turned out to have the through-hole blocked by growth and were able to unclog it. Before finding out though, we replaced the impeller and clean the raw water strainer (it was a little dirty bot not much).

Here's my full report on steam in the exhaust. https://ericsonyachts.org/ie/threads/cooling-system-upgrade-2020.17240/

Thanks Christian for pointing that out. It's nicely documented and will for sure be super handy if we have to do that too -which I'm afraid we may have to do. Patience as you said!

 

[Shaggy]

Hi, Marie -

That certainly does appear to be steam in the exhaust. Hopefully it is symptomatic of one of the more minor causes mentioned above. However, you may want to check a couple more things before running the engine again:

When was the last time the engine oil was changed? Have you looked at it recently? Take a look at the oil residue on the dipstick, or shine a flashlight into the dipstick opening to try and get a peek at the oil in the crankcase. The oil should appear golden or amber if changed recently, darker if not. However, if the oil appears "cloudy" or looks like chocolate milk, and/or if you have an abnormally high oil level on the dipstick, it could indicate a more serious issue.

The water pumps on these engines are mechanically driven and the impeller spins on a gear-driven shaft. There is a shaft seal behind the impeller that prevents the pumped seawater from entering the crankcase of the engine. If that seal fails, water will get into the oil and indicate as steam in the exhaust of a fully warm engine at all rpm settings.

Worse yet, as more water gets pumped into the crankcase, where it does not belong, it can fill up the crankcase to a point where the engine will have difficulty reaching full governed RPM, may begin to stutter and will eventually stop in a traumatic way due to hydrolock. The crankcase full of the seawater/engine oil mix will actually prevent the engine from being able to turn over at all.

Obviously you would want to avoid this situation!

One more telltale sign would be evidence of even a tiny water leak or residue from the water pump on the front of the engine.

Don't despair if this turns out to be the case. You (or your mechanic) would need to replace the impeller shaft seals and do two or three engine oil and filter changes in fairly quick succession, running the engine 30-40 minutes and up to full operating temperature each time.

Ask me how I know.... I avoided the full hydrolock situation, fortunately.

After the 3rd oil and filter change I still had a very tiny amount of steam in my exhaust. After an hour of running the engine in gear at the dock at about 2400 RPM, the steam was gone completely and has not recurred since. All of the non-oil moisture had fully been evaporated/expelled through the exhaust.

Obviously, I never dealt with my previous mechanic again, but the honest diesel mechanic who helped me through this ordeal said that as tough as these engines are, the engine will be just fine if the issue is dealt with promptly.

Not trying to alarm you, but I wanted to provide another avenue for you to inspect if you still have steam in your exhaust.

Best of luck and please keep us posted.

 

[Geoff W.]

Hi Marie, curious if you guys finished your exhaust experiments. I am also at the point where injectors + doing all the exhaust maintenance Christian did is on my immediate to-do list. My exhaust water definitely looks more like it's getting sprayed out at pressure than glugging out/pouring out as a lot of sailboats I see do.

I am also noticing more consistent white exhaust when motoring, rather than just starting. Also, it seems I am not motoring as fast as I used to at 2500 RPM - used to get me to 6kts easily but now am more around 5.5. Maybe I just have more stuff on the boat... bottom was recently cleaned. Really hoping it's not the head gasket..

Edit -

It gets to 3200 rpms as expected
Doesn't overheat or show higher than 160 in the cockpit readout
Starts fine after some glow, though still not a super fast start (likely injectors)

 

[MCD]

Hi Geoff and everyone on this thread,

We got caught up on other work upgrades that DNS'ed our boat, so the engine issues went down the priority list a little bit. As a result, we didn't end up doing the full exhaust system cleaning recommended by Christian.
But here is a little summary of where we did with respect to what was suggested on the thread (both for you and myself!):

• fuel-related:
  • We did change or clean the fuel filters and bleed the injector in the process. The fuel didn't look particularly dirty but that was our first time doing so as well, so we could very well have missed something. It didn't solve the steam problem but the start time was slightly reduced (30s of glow plug to 20s).
  • I recently added Stabil to the fuel but I haven't had the chance to check if it made a difference. Will check on our next trip.
  • We did the "easy" compression test by taking off the oil cap and no spill, so we assumed the compression was good and the head gasket was ok.
  • Possible other thing to do: service/replace the injectors.

• coolant-related:
  • We ended up adding up coolant as the plastic overflow tank seemed to never had seen coolant since we had the boat (and we also moved the tank to a more convenient location than above the trash). Not sure if more coolant had an effect but that was a while ago and I don't remember if we rigorously checked. But the coolant is now at least nice flowing back and forth from the overflow tank to the engine (or actually, overflowing fine but not everything is going back to the engine due to the lack of rigidity of the rubber hose that kinks).
  • We checked the engine temperature underway and no overheat.
  • We replaced the corroded coolant cap that was noticed during the survey.
  • Next on the list:
    • clean heat exchanger and raw water/exhaust circuit and our case replace the muffler. Let me know if the clean up fixes your problem if you end up doing it Geoff.
    • thoroughly check that we don't have a coolant leak.

• oil related:
  • We recently changed the oil and it was dark but didn't look milky. Once again, that was our first time doing it on this boat, so we may not be as accurate as an expert's eye. However, we had the oil analyzed during the survey and the result came out good. I think they would have picked it up if we had sea water in the oil, but I guess it's a pretty straight forward test so we may still check.
  • On the list: check if the oil texture/color.

• other things to check:
  • check speed full throttle underway: It should be 6-7 kt for 2300-2500 rpm with a 3-blade propeller (Christian), keeping in mind that the tachometer may have a wrong calibration (and even more so that in our case we just replaced the alternator and therefore it very likely needs re-calibration). Other "data point" (from Christian still): 5 kt for 1700 rpm.
  • check thermostat

I looks like our other project are wrapping up and that we may be able to finally go out again, which is gonna put the engine issues at the top of the list again. So I'll keep posting our progress if we make any...

Also, related to the long glow plug start that I had complained about earlier, and which had already improved with bleeding the injectors. We started the engine on our house bank for the first time and the engine started right away (less than 5s - our intention was not even to start it at that point, but rather test other things related to the alternator!). So it looks like our starter battery may be a little old and possible responsible for the long starts. Thinking of replacing it.

Thanks again for everyone's help and curious to see what happens to Delightful, if you go for the clean up Geoff.
Marie

 

[Jeff Uzl]

I love all the changes you made. The hoses are on my list of service replacements. However, I’ve been presented with an exhaust issue that I’d like your thoughts.
I have an 1988 E38-200 with an M-40 (5432) that a nipple connecting the exhaust to the water injector rusted off. I was planning on just replacing the nipple and be done but I am struggling getting the nipple out ot the 90 elbow.

I would have to do some major cabin disassembly to pull of the 90 degree elbow and I’m thinking of just redoing the piping as it comes off the engine. My concern is replacement parts and difficulty. Mostly of something doesn’t disassemble easily or properly.
I’ve shared some pictures.
Would love to know your thoughts.

 

[Loren Beach]

Is the engine under the galley counter or under the companionway?

 

[Kenneth K]

Undoing those rusted pipe fitting takes a "ton" of force, if it's even possible at all. The pipe sections make just break (like the broken section you have) before twisting out of their adjacent fittings.

It's unlikely you'd ever get enough leverage to remove them while they're still in the boat. I removed my entire manifold and exhaust riser when changing alternator brackets in 2016. I needed a 6 ft pipe to get the leverage to separate the riser from the exhaust flange. Luckily, the nipple stayed in the riser (which I replaced) and not in the exhaust flange when it came out. I was able to re-use the flange.


Your best bet is likely to remove the 3 bolts that hold the exhaust flange to the manifold. You will have to drain the manifold completely before doing this, as the flange forms the back-end seal for the coolant in the manifold.
(<--re-built riser and elbow)

Once you have the flange off, you can attempt removing the pipe fittings in your shop or garage. If you can't get the nipple out of the flange, you can buy a new flange and gasket for about $100 from Westerbeke.com.

Any pipe sections you replace should be 316 Stainless steel--these are available from any plumbing supply store. I read not to use galvanized pipe because it produces hazardous vapors when heated, and black-iron pipe, of course, rusts. Also, use Schedule 80 (thick-walled) stainless pipe and nipples, not Schedule 40 (thin-walled). Your plumbing supply store will likely have to order out for them.

 

[bigd14]

I had a similar issue and wasn’t able to separate the nipple and the flange. Another source for the flange here: https://www.catalinadirect.com/shop...e-exhaust-flange-rectangular/?SearchResults=1

 

[Jeff Uzl]

THANK YOU! This is exactly the help I needed. I hope the parts are readily available at Westerbeke.

 

[Jeff Uzl]

Is the engine under the galley counter or under the companionway?

Under the companionway.

 

[David Grimm]

I thumbed through this thread rather quickly, what temperature is your engine running at when it produces the smoke/steam?