MD2020 Engine Losing Antifreze

[Goofeyfoot]

For a couple of months, this engine was puking out white smoke, which I was told was unburned diesel. Mechanic said that a valve was costed with carbon or something. He advised that I run the engine and try to run it clean.

I ran it for maybe an hour today, in 10 minute increments.

In that time it drained the antifreeze reservoir completely dry.

There’s no antifreeze leaking anywhere on or under the engine that I can see, which makes me think that the coolant is making it into the combustion in some way.

Does anybody know what the problem is and whether it can be fixed?

Thanks.

Michael

 

[TrampBg]

Most probably blown head gasket.

 

[neilf39]

Possibly a leak in the heat exchanger between the seawater and fresh water circuits so it is going out the exhaust. White smoke may also be steam if it starts to come out a few minutes after running. Possibly a seal has gone in the heat exchanger. Is there a tinge to the water coming out the exhaust?

 

[Tamar]

Check the jubilee clips on the rubbers on the heat exchanger, if one has failed all the coolant will be lost

 

[Bobc]

Remove the exhaust elbow and check just inside the heat exchanger for corrosion. It's not uncommon for the material between the coolant and exhaust channels to corrode away leaving a hole from which the coolant escapes through the exhaust.

 

[PaulRainbow]

For a couple of months, this engine was puking out white smoke, which I was told was unburned diesel. Mechanic said that a valve was costed with carbon or something. He advised that I run the engine and try to run it clean.

You need a new mechanic.

 

[Bobc]

You need a new mechanic.

Absolutely. I can't believe how many times I see stuff like this. How these people get away with charging for their service amazes me.

 

[SteveA]

You need a new mechanic.

I agree Paul! The only contact there is between the coolant and SW is at the exchanger. As the engine warms up the coolant side is at a greater pressure than the SW hence any leakage will cause loss of coolant into the SW and then exhaust. This leakage could be from a failed tube stack, quite easy to remove and pressure test, or it could simply be leakage at the rubber endcaps.

 

[RichardS]

I agree Paul! The only contact there is between the coolant and SW is at the exchanger. As the engine warms up the coolant side is at a greater pressure than the SW hence any leakage will cause loss of coolant into the SW and then exhaust. This leakage could be from a failed tube stack, quite easy to remove and pressure test, or it could simply be leakage at the rubber endcaps.

That's not quite true. If the head gasket has gone then coolant could run into the cylinder, be expelled through the exhaust valve and then mix with seawater in the exhaust elbow. However, in the OP's case, I'm sure that this will not be the issue.

Richard

 

[179580]

For a couple of months, this engine was puking out white smoke, which I was told was unburned diesel. Mechanic said that a valve was costed with carbon or something. He advised that I run the engine and try to run it clean.

I ran it for maybe an hour today, in 10 minute increments.

In that time it drained the antifreeze reservoir completely dry.

There’s no antifreeze leaking anywhere on or under the engine that I can see, which makes me think that the coolant is making it into the combustion in some way.

Does anybody know what the problem is and whether it can be fixed?

Thanks.

Michael

Are you in the East Cornwall area? Sounds like the "Engineer" practicing his trade around here!

 

[Goofeyfoot]

Possibly a leak in the heat exchanger between the seawater and fresh water circuits so it is going out the exhaust. White smoke may also be steam if it starts to come out a few minutes after running. Possibly a seal has gone in the heat exchanger. Is there a tinge to the water coming out the exhaust?

No color to the exhaust water.

 

[Goofeyfoot]

Are you in the East Cornwall area? Sounds like the "Engineer" practicing his trade around here!

No, I’m not in Cornwall. I’m in North Carolina in the United States. Thanks.

 

[Bilgediver]

If your heat exchanger is the type with rubber end caps then make sure all the hose clamps are correctly tight. It is possible for the cooling water to pass to sea water due to a slack clamp. See page 12 in the manual.


Manual
http://mantaowners.org/wp-content/uploads/2012/11/Volvo-Do-It-Yourself-Manual-p1.pdf

 

[sailorman]

For a couple of months, this engine was puking out white smoke, which I was told was unburned diesel. Mechanic said that a valve was costed with carbon or something. He advised that I run the engine and try to run it clean.

I ran it for maybe an hour today, in 10 minute increments.

In that time it drained the antifreeze reservoir completely dry.

There’s no antifreeze leaking anywhere on or under the engine that I can see, which makes me think that the coolant is making it into the combustion in some way.

Does anybody know what the problem is and whether it can be fixed?

Thanks.

Michael

I woul look hor a head gasket leak hop u get sortedpdq

 

[Jim@sea]

I had a tractor which started to lose water, due to a bad engine casting the cylinder bore was thin and with wear became so thin that a hole appeared and every time the piston went down it was pulling water into the cylinder and expelled it through the exhaust valves.
A compression check found it.