Gearbox oil colour

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RadiumRob

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I commissioned an Engineer to inspect the engine of a boat I am in the process of buying. He found a sizeable patch of clean green oil beneath the engine, which he is confident is from a gearbox leak.

The owner disagrees with this, stating its a slight engine oil leak which he mops up and tops up.

I'm with the Engineer with this, as engine oil usually becomes black very quickly. Can anyone offer any views to support/refute either theory, and which scenario would be the worst/most costly to repair (Penta 2002).

The Engineer also spotted a broken mount and a very loose mount - not sure whether that is relevant beyond feeding my paranoia!

Thanks in advance!
 
Gearbox ATF is usually red (you could easily open the filler and check this). Greenish sounds like a spill when the engine was recently topped up with oil. So perhaps an engine with heavy oil consumption, or maybe a hurried attempt to make good a neglected oil level prior to the inspection.

If the engine has been run awhile with damaged mounts and subsequent mis-alignment, that might result in a number of faults including gearbox wear.

In all, a suspicion that this engine has not been well maintained. It could well be fine, but you should check it running.
 
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AndrewB said:
Gearbox ATF is usually red (you could easily open the filler and check this). Greenish sounds like a spill when the engine was recently refilled with oil. So perhaps an engine with heavy oil consumption, or maybe a hurried attempt to make good a neglected oil level prior to the inspection.

If the engine has been run awhile with damaged mounts and subsequent mis-alignment, that might result in a number of faults including gearbox wear.

In all, a suspicion that this engine has not been well maintained. You should check it running.
Click to expand...

Not all gearbox`s use ATF
 
AndrewB said:
Gearbox ATF is usually red (you could easily open the filler and check this). Greenish sounds like a spill when the engine was recently refilled with oil. So perhaps an engine with heavy oil consumption, or maybe a hurried attempt to make good a neglected oil level prior to the inspection.

If the engine has been run awhile with damaged mounts and subsequent mis-alignment, that might result in a number of faults including gearbox wear.

In all, a suspicion that this engine has not been well maintained. You should check it running.
Click to expand...

he has employed an Engineer to check it on his behalf
 
Have you wiped some oil from each of the dip sticks (engine and gear box) to see if it matches the green oil ?
The only green stuff I have seen under an engine is coolant. Are you sure it is not oily antifreeze ?
 
Well you really have a choice here. The owner who has to re-fill, is much more likely to know the real cause than an engineer so the question is - is the owner telling porkies and if so, why? Or to put it another way, if the owner is filling the engine and the gearbox is leaking you would expect the box to be near empty and the engine over full.

The colour of the oil is no real guide - my engine oil takes at least 10 hours running before it starts to go even a bit black. The smell of the oil would be a guide if the box was filled with hypoid but I cannot remember what the Volvo box takes. Engine oil at a guess.

From his perspective I can see no gain in telling porkies - there is little real difference in terms of problems / work involved in curing the leak. Both would require that the engine be moved off its bearers and the gearbox split off. Did it on my current boat where the leak was the rear crankshaft oil seal. Not a difficult job except for the confined working area.

The mounts could be influencing it. If the engine is moving excessively, the output shaft from the box might be compressing the lip seal unduly and causing a leak. Either way the bearers need replacing and from past experience of the 2000 series ( even Volvo said it was a barsteward to balance and as a result they had several series of different engine mounts during its production life) you need to replace all 4 at the same time. just 2 doesnt work - I tried it.

All second hand boats have issues - they are second hand and used after all so dont expect "new". Engine problems are some of the easier to deal with. Its things like wet decks that you ned to run a mile from.
 
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Halo said:
Have you wiped some oil from each of the dip sticks (engine and gear box) to see if it matches the green oil ?
The only green stuff I have seen under an engine is coolant. Are you sure it is not oily antifreeze ?
Click to expand...

No access to boat now, but if I buy that will be one of my first routes of investigation. Thanks.
 
wotayottie said:
Well you really have a choice here. The owner who has to re-fill, is much more likely to know the real cause than an engineer so the question is - is the owner telling porkies and if so, why? Or to put it another way, if the owner is filling the engine and the gearbox is leaking you would expect the box to be near empty and the engine over full.

The colour of the oil is no real guide - my engine oil takes at least 10 hours running before it starts to go even a bit black. The smell of the oil would be a guide if the box was filled with hypoid but I cannot remember what the Volvo box takes. Engine oil at a guess.

From his perspective I can see no gain in telling porkies - there is little real difference in terms of problems / work involved in curing the leak. Both would require that the engine be moved off its bearers and the gearbox split off. Did it on my current boat where the leak was the rear crankshaft oil seal. Not a difficult job except for the confined working area.

The mounts could be influencing it. If the engine is moving excessively, the output shaft from the box might be compressing the lip seal unduly and causing a leak. Either way the bearers need replacing and from past experience of the 2000 series ( even Volvo said it was a barsteward to balance and as a result they had several series of different engine mounts during its production life) you need to replace all 4 at the same time. just 2 doesnt work - I tried it.

All second hand boats have issues - they are second hand and used after all so dont expect "new". Engine problems are some of the easier to deal with. Its things like wet decks that you ned to run a mile from.
Click to expand...

Sounds like I need to get the Engineer to change all mounts and source the leak at the same time then. Your last paragraph rings very true - I suppose the worst case is to re-engine, which has some advantages in addition to losing the leak.
 
Assuming that the oil is from the gearbox for a moment, the leak can only be from seals, either the input end from the engine or the drive to the shaft, or a remote possibility that it is the one on the change lever. The seals themselves cost a pound or two, dependent upon the installation it shouldn't take more than half a day to change them and maybe considerably less. A leak does not indicate a major fault and I would not let it put me off.

I suspect it more likely to be engine oil. After just a few hours of use the small amount of carbon in new oil can give it a greenish tinge. Another thought - Is Duckhams oil still green? Does it still exist?
 
vyv_cox said:
Another thought - Is Duckhams oil still green? Does it still exist?
Click to expand...

I think not. It went into Castrol and first they dropped the green colour (which was marketing not technical I believe) and later dropped the brand AFAIK.

As I recall, the manual for my 1985 VP2002 said you could use ATF or engine oil 15-40CD in the gearbox.
 
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