Is my engine dead?

[Stewie12]

Sounds like a cylinder head gasket to me. Use the KISS principle and go for the obvious.

[Scubaseas]

Don't trash the engine for the sake of a head gasket or even a cracked head. Blown head gasket may effect the compression reading. There are a several ways to determine a blown gasket.

If you are not familiar with engine maybe hire a mechanic to diagnose it for you.

One way to diagnose is to put a pressure tester on the coolant reservoir, pump to 14 psi and let sit. Take out injectors or glow plugs. Crank over engine. If coolant/water comes out you have a blown head gasket. Another way is pump up the cooling system , let sit over night then try and hand crank the engine over. Careful as the engine may be hydrolocked. Unlock by removing glow plugs or Injectors then cranking over.

Another way is a leak down test but you will need a compression tester fitting, a leak down tester and compressed air to do this.

Another way is to fill the cooling system and leave the cap off then crank the engine over. If water shoots up into the air you have a head gasket or head issue. This only works on BIG leaks.

Another is to leave the coolant pressure gauge on and run the engine. It will slowly build pressure due to normal thermal expansion but once up to temp it should hold steady. If you warm up the engine and with it running the pressure continually builds up then yes, you have a blown gasket or warped or cracked head. This is a good way to check for small leaks.

If you have a blown head gasket you should start to see the engine oil start to look like a chocolate milkshake. This may take a couple of hours or even longer to happen.

Rule out salt water smoke by running the engine without the raw water going to it for about 2 to 3 minutes when the engine is cold. If the smoke stops you have a problem where raw water is getting into the engine somewhere. Possibly at the mixing elbow. Watch the exhaust hose doesn't get too hot when doing this but you can run the engine for short periods without raw water going to it.

Possible you de-tempered the piston rings but I kinda doubt it. You would need to get the head off to tell you if then fixing the boat is worth it or not by looking at and measuring the bores.

NCBoatrx has a good plan. Ditto pete7 Look at Youtube "Bums on a boat" who just took their head off of a MD2030 which is the same beast. It's really not hard to do.

Does the smoke smell like oil and leave a sheen on the water? Or does it smell like steam from a kettle? Or smell like diesel and also leave a sheen on the water?

[ABJ87]

Good advice above, just a couple of comments. Injectors can also cause white smoke, does the exhaust smell like fuel or slightly sweet (coolant). Pressure testing the cooling system will tell you for sure, many auto parts stores in the us rent testers.

[sv mintaka]

When I bought my boat I looked at the kubota diesal engine and said I hoped it never broke down as I would not have a clue how to fix...long story short I ended up taking the head off, grinding the valves, putting in new injectors and head gasket finishing off with a new altenator. Runs like a charm now and was not difficult to do with the right help. All done in the boat on a mooring buoy!
A few tips: make sure you have a torque wrench with a long handle, the pattern to undo and do up the head bolts, add a little oil to threads of the bolts before putting back in and lots of patience. Hope this helps

[zstine]

White smoke Sounds like a blown head gasket. Others have given methods to test.

It is running. So definitely NOT Dead!

It is possible to DIY the head gasket if you have some technical aptitude. The parts are not expensive, but the labor may be if you need to pay for a tech... However, It is still WAY cheaper than a repower. So, NO your engine is not dead! Time to become a grease monkey

[Clivevon]

I would not consider myself inclined to be mechanically all that knowledgable but I will chip in my 2 cents worth:
Despite the above, I did many years ago completely strip down & rebuild a car engine & got it working - at the time it was a case of needs must, although I didnt know what a tappet was when I started. I got a good workshop manual & went from there - it is surprising what you can do if you have to.
Also I recently (5 years ago) paid a professional to install a new engine. Buying the engine was less than half the total bill... (needed new everything else while at it, also the prop on the old Volvo MD17D engine turned the opposite way to the new Beta 35). Which way does your prop turn?
Before scrapping your engine: Why did the engine overheat in the first place? Lack of water in the system or some other problem?
You say the mechanic replaced the heat exchanger tank. What is that? Do you mean the heat exchanger (because it was blocked up), or the coolant expansion tank (because it was leaking)??
If it is your head gasket blown, the white "smoke" will not be smoke at all. It will be steam because your coolant is getting through the blown gasket, into your combustion chamber, & being blown out of your exhaust as steam. We all have water cooled exhausts of course which makes it more difficult to tell but you might try seeing if the "smoke" condenses into water on a cold surface (say a freezer pack) held above it?
The 2nd & more important issue is that your coolant will also be contaminating your engine oil causing more engine damage. Check your dipstick - does the oil look good or has it got milky white stuff in it where the coolant is affecting it?
The 3rd issue is to not run the engine too much in this condition as you will make the head gasket leak worse & cause more damage. The cylinder head & engine block jointing faces are now exposed to high compression gases from your combustion chamber which could soon erode a channel into the metal which means that a new gasket will not fix the problem as you will also have to have the joint faces skimmed (if that is possible) to get rid of the erosion channel so you can make a gas tight joint.
The previous recommendation to ask around for 6 mechanic recommendations is a good one. A head gasket repair could be very straightforward giving you years more service from that engine. The reason I replaced my engine was down to lack of availability of spare parts at reasonable prices, as it was 35 years old. You may not have that problem. Good luck.

[Cadence]

Originally Posted by Lepke

Overheating can do anything from no damage to major damage. It depends on how hot for how long. Since you know little about engines, you'd probably be better off with a new working engine. Spend the money all at once instead of one part at a time.The average marine isn't going to be much help except for emptying your wallet.

I seldom disagree with Lepke, I do on this. It would be worth the money to get a qualified opinion. It would also depend on engine hours.

[johnn33]

MD2020 I suddenly found coolant on my saloon floorboard (above a very flat bilge). The poorly designed heat exchanger has two black rubber moulded ends secured with Jubilee clips keeping fresh water with coolant apart from the sea water. One had moved and also the exhaust elbow where warm seawater cools the exhaust gases had become partially blocked. The engine was unharmed. Heat exchanger rebuilt and a stainless steel non-Volvo elbow fitted. The newer Volvo models have proper metal ends for the heat exchanger.

John

[roverhi]

If you can isolate the problem to the head gasket or head, pulling the head on an engine is not rocket science and it doesn't require pulling the engine to do if you have access. While the head is off use 'cottontail's' ring test to find a wasted cylinder. Would have a mechanic come in and check the pistons, cylinders and block checked out for wear and cracks. That's something you certainly don't have the experience to evaluate. With the head off would have a valve job done with new valve guides and injectors rebuilt. It's a relatively inexpensive way to get good as new performance from the engine. Removing the head can be done in a day and reinstalled in less time as you'll have developed some expertise and knowledge working on the engine. You will need a torque wrench to reinstall but it can be rented. Other than that basic tools are all that's required and, depending on your engine room, the flexibility of a yoga instructor.

[Wotname]

Originally Posted by sandy stone

.................
You didn't say what kind of boat you have, but I can't imagine you would have to remove the engine just to pull the head.

Originally Posted by LittleWing77

It's a boat that's got a Volvo engine in it. ...............

The OP's profile says he has a 33 Dufour GibSea.

[thunderhoof]

My MD2030 developed a leak in the heat exchanger (corrosion) that allowed water into the exhaust manifold - resulting in continuous white steam in the exhaust. You might remove the heat exchanger body and the exhaust mixing valve and inspect them. They will have to come off anyway if you have to remove the head.

[dw1979]

A relatively inexpensive early warning to an over heat situation cause by lack of raw water flow is available from several sources. I recently installed a unit from Borel Mfg, but there are other suppliers also. This device straps a sensor on your exhaust hose just as it leaves the engine. It will give an almost instant alarm if the raw water is not present. (Watching the temp gauge will not give you fast enough warning that something is amiss). A similar device might have saved you going thru the repair/replace situation you are now in.
I suggest that once you get things back to normal consider installing this for piece of mind.

[Puregravy]

I have the same engine and had to replace the head due to a rocker arm malfunction. Long story as to a new head. Turns out that this engine is a marinized Perkins and was able to find parts through a company in England that were a fraction of the price of going through Volvo dealer. They had over the years been able to cross reference Volvo part numbers for the same Perkins part. That particular Perkins is used world wide across platforms so parts are readily available and reasonable. Check out parts 4 engines dot com. Mechanics in our area were flat out busy at the time and my mechanic offered to stop by and mentor as required. I used him initially and was able to complete the job through the use of a manual and a bit of YouTube. With new mixing valve, head, heat exchanger boots and assorted parts I spent about $3K CND.

[SOLAR SUPPORT]

Originally Posted by johnn33

MD2020 I suddenly found coolant on my saloon floorboard (above a very flat bilge). The poorly designed heat exchanger has two black rubber moulded ends secured with Jubilee clips keeping fresh water with coolant apart from the sea water. One had moved and also the exhaust elbow where warm seawater cools the exhaust gases had become partially blocked. The engine was unharmed. Heat exchanger rebuilt and a stainless steel non-Volvo elbow fitted. The newer Volvo models have proper metal ends for the heat exchanger.

John

Good point. Md-20/30/40 VP motors' elbow was made from iron cast. Replace your elbow with a SS 316L made one even if you have a new engine. This part is like a cancer cell for your exhaust manifold and overheat issues observed with VP Md-20/30/40 series.

Michael If you can't find an affordable 316L S. Steel made Elbow for your engine please let me know. I can supply one for you. EMail : volkangorciz@hotmail.com

[Paul Carey]

I don't think you mentioned hours run , on this range of engines, overhaul can start @ circa 3000 hrs unless it has been maintained excesevily beyond V/P recomendations , White smoke is indictitive of head & or head gasket problems & this family of engines do have a reputation for head cracks , particularly if a water heater is in cct ..Now we all know that V/P don't make anything themselves (only money) but these engines are rebadged Perkins Peramas & writing here from limey-land I believe that in the US Perkins support is better than V/P ? ..If you are not the grimy fingernail type , you don't have to use specifically a marine engineer , this work should be well in the remit of a small town auto mech whom should know local machining shops whom can rework the head . with the head off you can check the bore wear ,, get the injectors recalibrated at a diesel shop ,, & save on renewal ,,,