Jump to content

Water,water everywhere (inside my engine!)


Featured Posts

Hi

 

I recently bought a 40ft narrowboat powered by a BMC 1.5L diesel with standard marinisation using dry exhaust. The original engine had been trashed by mechanics unknown and proved a basket case.

 

I obtained a second hand engine which looked pretty good. I fitted this engine and initially it ran well. After about twenty hours normal running the following occured. The boat was moored up while I was carrying out renovation work. Having flattened the batteries somewhat I ran the engine on tickover in order to recharge the batteries for about twenty minutes. I then noticed white smoke from the oil filler cap and immediately shut the engine off. Examination of the rocker cover and dip stick showed water emulsification of the engine oil. However the engine had not overheated and there was no significant visible water loss from the main coolant header tank.

 

Having been scratching my head for a few days to try and work out if this was a simple head gasket failure although there was no usual build up to this. Today I removed the exhaust pipe connection from the manifold. To my surprise there was about 3 pints of clean, clear water inside the exhaust system. The outlet to the exhaust is well above water line and I can see no reason how water could have entered from the outside.

 

The level of the outlet is about 4.5 inches above the height of the manifold connection. Is this OK, normal?

 

Can anyone advise me on this failure as I am a bit puzzled.

 

thank you

 

Paul Jackson

Edited by jacksonp_uk
Link to comment
Share on other sites

Hi

 

I recently bought a 40ft narrowboat powered by a BMC 1.5L diesel with standard marinisation using dry exhaust. The original engine had been trashed by mechanics unknown and proved a basket case.

 

I obtained a second hand engine which looked pretty good. I fitted this engine and initially it ran well. After about twenty hours normal running the following occured. The boat was moored up while I was carrying out renovation work. Having flattened the batteries somewhat I ran the engine on tickover in order to recharge the batteries for about twenty minutes. I then noticed white smoke from the oil filler cap and immediately shut the engine off. Examination of the rocker cover and dip stick showed water emulsification of the engine oil. However the engine had not overheated and there was no significant visible water loss from the main coolant header tank.

 

Having been scratching my head for a few days to try and work out if this was a simple head gasket failure although there was no usual build up to this. Today I removed the exhaust pipe connection from the manifold. To my surprise there was about 3 pints of clean, clear water inside the exhaust system. The outlet to the exhaust is well above water line and I can see no reason how water could have entered from the outside.

 

The level of the outlet is about 4.5 inches above the height of the manifold connection. Is this OK, normal?

 

Can anyone advise me on this failure as I am a bit puzzled.

 

thank you

 

Paul Jackson

 

 

Is it safe to assume (being a narrowboat) that this should be a dry exhaust, there are a number that are not and if yours is one of them then apart from the "clean" description its normal. However the run of the exhaust needs checking in case water can run back into the manifold and the into a cylinder and past the rings into the sump.

 

iF it is a dry exhaust, the tick-over bit may be a clue (but again its the "clean" water that mystifies me - I would have expected sooty). Any internal combustion engine will produce vast quantities of water vapour in the exhaust and if left at idle the exhaust may not have heated up so much of it could be condensation. However this should not explain the water in the sump.

 

Without anything more to go on I fear an internal crack. Possibly in the exhaust manifold, but more likely head or block. Once you are sure it could not have got in from outside (partial sinking type situation)I think the head may haver to come off (in case its the gasket) and then some pressure tests done.

 

A completely "off the wall" suggestion. I do not suppose you connected the breather hose that should be fitted between a "stub" on a cover below the manifolds and the air cleaner to the cooling system?

 

Tony Brooks

If

Link to comment
Share on other sites

Is the exhaust run sloping down from the exhaust skin outlet back to the manifold instead

of running down to the outlet ??

Could it be rain water getting through the skin outlet and dribbling back down towards the engine ?

Link to comment
Share on other sites

Is the exhaust run sloping down from the exhaust skin outlet back to the manifold instead

of running down to the outlet ??

Could it be rain water getting through the skin outlet and dribbling back down towards the engine ?

 

Hi

 

Thanks for your advice. I think that rainwater from the outlet may well be a strong possibility. The exhaust system does slope back by 4.5" overal to the manifold connection. At present the boat is stern moored with the outlet very close to a pontoon. Last week there was some serious rain and the bilge had collected 4". I suppose it is possible that water running off the pontoon boarding could possible enter the outlet pipe. (Murphys law!) The quantity of water in the system would suggest to me that the engine would not have run at all last week and the water was clear. Also the header tank level has not dropped at all and there must have been 3 pints in the system.

 

cheers

 

Paul Jackson

Link to comment
Share on other sites

Hi

 

Thanks for your advice. I think that rainwater from the outlet may well be a strong possibility. The exhaust system does slope back by 4.5" overal to the manifold connection. At present the boat is stern moored with the outlet very close to a pontoon. Last week there was some serious rain and the bilge had collected 4". I suppose it is possible that water running off the pontoon boarding could possible enter the outlet pipe. (Murphys law!) The quantity of water in the system would suggest to me that the engine would not have run at all last week and the water was clear. Also the header tank level has not dropped at all and there must have been 3 pints in the system.

 

cheers

 

Paul Jackson

 

 

I think you would be well advised to try to fit a swan neck in the exhaust in the form of an inverted U. Right up to under the deck. Between silencer and outlet would be ideal if it is rain, or if that is difficult between engine and silencer. If that proves to problematic at least fit a "low section" to contain the water in either of those two places.

 

I am a bit mystified how such a quantity of water found its way through the silences. I would have expected it to have soaked the lower half of the wadding first.

 

 

Tony Brooks

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.