Get my engine running again - dealing with the emulsified oil

[chris-s]

In simple terms, I'm pretty sure the head gasket failed on our VP2003 at the weekend, I can't NOT try to fix it. We have not reached the stage of fitting a refurb or re-engining yet.
Before we get there, any POSITIVE tips or advice on getting THIS engine running again would be greatly appreciated. To all you doom-and-gloomers, don't, just don't, there is plenty of time for that later!

History
Last season, our first with this boat, the engine performed faultlessly. Certainly it is a high-hours engine, a little tappety but it is tidy, doesn't leak, starts on the button and drives well.
We put sixty hours on it last year with oil and filter changes at the start and end of the season.
Being a raw-water cooled variant, we flushed it with ProFlush at the beginning of last season and again when we hauled out just as a preventative measure as I don't think it had been flushed in some time,
although we have had no indications of overheating.
New impeller each season, no leaks or drips from the water pump and it's always pumped water quite happily.
Thermostat was also replaced just as a matter of course at the end of last season, tho the existing one tested fine, yes, the correct one for raw water.
We also fitted a Silicon Marine dual sensor unit to the exhaust and on the thermostat housing last season and its never shown anything of concern.
No visible oil or water leaks from around the engine/block or traces of water in the oil (until now).

This season
The engine was run multiple times whilst ashore leading up to splash day, nothing to note.
The boat was launched less than a fortnight before, a short motor to our mooring and a little motoring the previous weekend, no concerns.
The only comment I'd make is that the tickover seemed a little lower circa 600rpm.

The fateful journey
The journey was an eight mile trip to the Helford from Flamouth, unfortunately the wind and swell was such that we had to motor most of the way.
All seemed fine, although in the last mile approach to the moorings we did notice a little steam coming out of the exhaust, not billowing out in clouds, just a little.
Temps all good and plenty of cooling water otherwise. RPM note did drop a little a couple of times, but I put that down to possible slippage/knock of the throttle lever as a little touch
restored them. Moored up, switched off and then almost immediately, decided to take a different mooring, so restarted without issue and relocated.
A little niggle in my head made me check the oil, no issue, clean and plenty of it.

Later in the evening, with the steam/rpm thoughts still niggling away, I started the engine, it started fine, but it was not sounding quite right, gave it some revs, lots of 'smoke/steam', throttled back to
idle and it petered out. Checked the oil and it had emulsified and the fluid level was higher than earlier (should have checked before starting it possibly?)
With two top-end gasket kits onboard, the only thing missing was a torque wrench, probably just as well.

The Plan
So here we are, less than two weeks into the season with a dead engine, before we get into the discussions and virtues around repair or replacement engines etc, step one is to assess the damage.

The assumption is that the head gasket has failed, hopefully without too much other damage and the optimistic thoughts are to do a top-end overhaul without removing the engine. All well within my capability.
We are also assuming that it wasn't the raw water pump that allowed water into the engine given that there have never been any external signs of it leaking and that it wasn't exhaust elbow related as that was replaced in 2022.

Before I take the head off, is there anything I can do to help identify other possible damage which I couldn't do so easily after taking the head off?
A compression test for the rings comes to mind, but not sure I want to spin the engine much in its current state and its probably meaningless with a blown head gasket anyhow.

Happier days..


PS I have watched the YT videos from RAN Saling and Sailing Brittany cover their VP2003 rebuilds, straightforward and encourging stuff.

 

[AntarcticPilot]

Just to encourage you, I'm no mechanical wizard and my wife and I successfully did a top-end service on our VP 2003 a few years ago. As I recall, the hardest bit was getting a good seal round the valve cover! Also, seat all the water pipes carefully BEFORE tightening the securing yokes - trying to seat them by tightening the yokes will result in leaks. Guess how I know! Take care with the banjos on the injectors; the original VP ones are very weak and overtightening them will cause them to shear, Again bitter experience! Some VP agents can supply a bolt that is much stronger (Volspec, for example).

You'll have the exhaust elbow off - it's very much worth checking for any build-up of deposits or blockage of the water channels. Also, there's a water distribution pipe that runs through the block; the holes in the side of that pipe can also get blocked fairly easily and it's worth giving it a good clean.

 

[chris-s]

Just to encourage you, I'm no mechanical wizard and my wife and I successfully did a top-end service on our VP 2003 a few years ago. As I recall, the hardest bit was getting a good seal round the valve cover! Also, seat all the water pipes carefully BEFORE tightening the securing yokes - trying to seat them by tightening the yokes will result in leaks. Guess how I know! Take care with the banjos on the injectors; the original VP ones are very weak and overtightening them will cause them to shear, Again bitter experience! Some VP agents can supply a bolt that is much stronger (Volspec, for example).

You'll have the exhaust elbow off - it's very much worth checking for any build-up of deposits or blockage of the water channels. Also, there's a water distribution pipe that runs through the block; the holes in the side of that pipe can also get blocked fairly easily and it's worth giving it a good clean.

Thanks for the support! Have had plenty of experience with the cooling pipes, always using new seals helps, and I know the distribution pipe is clear as I shoved a boroscope down it after the last flush.

 

[SimpleSailor]

One step at a time, take some pictures before you remove bits, You will then know where to put them back! If you can get some sort of tray or receptacle under where you are undoing bits it might save some bilge diving! Have a container at hand, in a safe spot, for the bits you don't drop in the bilge. Don't just dive in and start taking things apart, stop and have a think. You will probably find it is not as daunting as you may think. Think of the satisfaction when you press the button and it roars into life.

 

[neil_s]

Before you take the cylinder head nuts off, check the torques - this might give you a clue as to why the gasket failed.

 

[steveeasy]

From what you are saying I think the clue to the problem is water has got in to the oil.
I don’t know your engine type at all but someone will be able to identify possible causes..there might be a chance your not need to remove the head just identify the cause of the water entering the oil and fixing that. That’s the positive approach. When it happened to my tractor it was pourus piston liners but a completely different engine.

Steveeasy

 

[AntarcticPilot]

From what you are saying I think the clue to the problem is water has got in to the oil.
I don’t know your engine type at all but someone will be able to identify possible causes..there might be a chance your not need to remove the head just identify the cause of the water entering the oil and fixing that. That’s the positive approach. When it happened to my tractor it was pourus piston liners but a completely different engine.

Steveeasy

The 200x series are very straightforward engines, and the only realistic pathways for water to get into the oil are the cylinder head gasket or just possibly through the oil and water seals on the water pump going. But the latter wouldn't stop the engine from running, and there would be a noticeable water leak behind the water pump. There are no cylinder liners and the block is a heavy casting with plenty of metal between the water galleries and the cylinders. They're designed for raw water cooling.

 

[chris-s]

Removing the emulsified oil... this is one of the first things I assume I should do to prevent any corrosion occuring intenrally given it will be several weeks (in my dreams) before re-assembly, or is corrosion unlikely given it is a very oily-salt water mix? If I do remove it, should I replace it temporarily with something like a diesel/oil mix or just 'engine oil'? Should I temporarily 'overfill' it to maximise coverage around the crank or even hand-crank it in an attempt to get it pumped thru the system?

 

[Refueler]

Removing the emulsified oil... this is one of the first things I assume I should do to prevent any corrosion occuring intenrally given it will be several weeks (in my dreams) before re-assembly, or is corrosion unlikely given it is a very oily-salt water mix? If I do remove it, should I replace it temporarily with something like a diesel/oil mix or just 'engine oil'? Should I temporarily 'overfill' it to maximise coverage around the crank or even hand-crank it in an attempt to get it pumped thru the system?

Personally ? I would drop out all the old emulsified oil .. get the cheapest light oil you can find and refill to max mark ... start engine - stop engine - it was just to get oil flushing round the system ... drain and check oil .. see what comes out.
Do your work on engine ... then maybe use that cheap oil again as a first flush start .. then drop it all out and if all well - refill with correct oil.

 

[chris-s]

Personally ? I would drop out all the old emulsified oil .. get the cheapest light oil you can find and refill to max mark ... start engine - stop engine - it was just to get oil flushing round the system ... drain and check oil .. see what comes out.
Do your work on engine ... then maybe use that cheap oil again as a first flush start .. then drop it all out and if all well - refill with correct oil.

So something like a cheap semi-synthetic 5w-xx would be fine for this, given the recommended oil is a mineral 15-40 and I can't find a lighter weight mineral engine oil. It will no doubt have multiple oil changes before we are done anyhow.

 

[Refueler]

So something like a cheap semi-synthetic 5w-xx would be fine for this, given the recommended oil is a mineral 15-40 and I can't find a lighter weight mineral engine oil. It will no doubt have multiple oil changes before we are done anyhow.

It really will not matter as you will use it as a flushing medium and to check whether it has water in it when drained ... the cheapest you can find ... and of course a few filters to go with it !!

 

[david_bagshaw]

I would add, as you wont be running the engine for long, would consider disconnecting its cooling water, along with putting light oil on top of the pistons while the head is off to help cleaning the ring lands of gunge and protecting the bores. expect to do alt least 4 running oil changes to remove all the emulsion.. from my experience of a stationary when dunked 4 stroke outboard.

 

[chris-s]

I would add, as you wont be running the engine for long, would consider disconnecting its cooling water, along with putting light oil on top of the pistons while the head is off to help cleaning the ring lands of gunge and protecting the bores. expect to do alt least 4 running oil changes to remove all the emulsion.. from my experience of a stationary when dunked 4 stroke outboard.

Yes, I was planning on draining any remaining coolant and making sure the inlet turned off, let’s not make things any worse!
It has a decompression lever so I will raise that and turn by hand to begin with.

 

[ylop]

or is corrosion unlikely given it is a very oily-salt water mix?

Is it raw water cooled? should it not be a mix of oil and your coolant? (which probably has some corrosion inhibitors in it).

 

[chris-s]

Is it raw water cooled? should it not be a mix of oil and your coolant? (which probably has some corrosion inhibitors in it).

Yes, it is raw water cooled.

 

[B27]

I had a car ages ago with emulsified oil, lots of black 'margarine' in the rocker box.
If there is a build up of this kind of stuff, you might not remove much of it by just changing the oil.
Especially without getting the engine hot.
Maybe look inside the rocker cover first?

 

[Tillana]

I'm not familiar with the engine, but I had water pass the seals on my md11c and get into the sump without any signs from outside. The weepholes on the pump were blocked with crud. Does it have a similar water pump. Are the weepholes clear?

 

[AntarcticPilot]

I'm not familiar with the engine, but I had water pass the seals on my md11c and get into the sump without any signs from outside. The weepholes on the pump were blocked with crud. Does it have a similar water pump. Are the weepholes clear?

If the seals fail there's an obvious leak. Basically there are two identical seals back to back with a gap between them, one keeping water in the pump and the other keeping oil in the crankcase. So both seals have to fail for water to get into the crankcase, and it's actually unlikely that much water would get from the pump to the crankcase by that route, as the water has an easier path to the outside than to the crankcase. I wouldn't discount it as a possible pathway, but I think it would be very easy to diagnose.

 

[Tillana]

I replaced the seals and bushing with a kit, but the shaft itself was heavily scored. There was no obvious leak as the holes were filled with general engine grime. It was an easy job to take the pump off and refurbish

 

[chris-s]

Right then, first step done. I removed most of the oil, thick grey soup which neither the electric extraction pump nor pela style would touch, so it was down to the little brass hand pump. It took a while, but then fiilled with fresh oil and a new filter, removed impeller and drain any coolant (raw water cooled), decompressed it and turn it by hand first and it felt fine, so blipped it on the starter a few trimes with the stop lever pulled, all seems fine, so there was nothing left to do but fire it up.

It started fine and didn't sound too bad either. I did half a dozen or so short runs, like 20-40 seconds at a time, bearing in mind there is no exahust coolant either. Plenty of smoe out of the exhaust but no horrible sounds.

Checked the oil, mucky but thinner so the second oil change was muich quicker. Repeated the short start-stop runs after the second change and then checked the oil again, pretty darn clean, cleaner than the mess I made. Need more paper towel!

I will get some more oil and filters tomorrow and repeat the process a couple more times just to be happy I have as much of the crap out as possible.