Oil in cylinders, any quick suggestions!!

pcatterall

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I have refitted the head on my Perkins 4108.
The original pistons, rings etc were all as they should be and I had relapped and fitted the valves. tappets were adjusted and the rocker cover replaced.
Later I added the correct quantity of oil.
While turning the engine by hand ( looking at the fuel pump rod) I found loads of oil being pumped out of the open injector holes.
I can see that while filling the engine a very small amount of oil could get down the valve stems but not the amount sitting on the pistons.
I can only guess that somehow there is a restriction/blockage which prevented the oil from getting down to the sump but then there is no way that the rocker cover could contain the volume of oil I put in.
Am I missing something!! ??

Edit Just looking at the other engine and there seem to be plenty of passageways for new oil to drain quickly from the rocker box down into the sump. Some head scratching going on here!
 
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As you say, oil drains quickly from the rocker box down into the sump and does not go anywhere near the cylinders. The only place that oil can get onto the pistons is, indeed, past the valves but it the valve stems or guides are not hopelessly worn I cannot see how much oil can get down even if the valve stem seals were worn or missing. I assume that the valve stem seals were replaced during the rebuild?

When I rebuild an engine I do use a lot of oil on the bores and on the valves which means that when the engine first starts there is a huge amount of blue smoke emitted for the first few minutes. Are you sure that the oil is not simply the remnants from the rebuild?

Richard
 
Don't know the Perkins, but on many engines oil passes to the valve gear via drill-ways crossing the block/head interface. If the head gasket isn't installed correctly then oil can leak into the nearby bore. Shouldn't expect all cylinders to be affected though.
 
Don't know the Perkins, but on many engines oil passes to the valve gear via drill-ways crossing the block/head interface. If the head gasket isn't installed correctly then oil can leak into the nearby bore. Shouldn't expect all cylinders to be affected though.

That's true but I'm sure that a wrongly installed head gasket would only result in oil going to the wrong place (and even then, probably not the bores) when the engine is running and the oil is being pumped. I think that oil always drains under gravity from the rocker box to the sump so the head gasket cannot exert any influence.

Richard
 
Thanks,
Good long shot but the breather is not connected! Seals on valve stems, only light oil used on bores.
Did I have a senior moment and pour oil into intake?? don't think so !! Open to more suggestions!

You're going to have to remove the rocker cover and see what's going on. That should be a simple job unless access is very restricted. The only way that large quantities of oil can get from the rocker box into the cylinders is through the valve guides excepting something extreme like a cracked cylinder head. Obviously oil can be introduced though the exhaust or intake ports but that, as you say, would be impossible if the only place that you actually poured any oil was into the filler hole in the top of the rocker box.

If that much oil is coming out it can only be because one or more valce spring collets have not been fitted properly and the valves have dropped into the cylinder or something equally unlikely. However, I don't see how the engine would actually turn a full revolution.

Once you remove the rocker box and turn the engine over you will soon see if something major is amiss.

Richard
 
The most likely cause is oil passing through the valve guides, but guides wear out gradually, with small amounts of oil passing through. Do a visual inspection through the rocker cover and if all looks good, put the cover back and start the engine, after one minute the oil should burn out, if the engine carrys on with huge amont of smoke from the exaust, especially when revving up, then you will know that something critical is wrong; if this is the case, the cylinder head has to be removed again for close inspection to determine the fault. Good luck.
 
Did you empty the sump before you did the work? Sounds daft, but if you filled the engine oil on top of an already full sump the engine will be awash with oi which will creep up past the rings. I am sure you are not that daft, just putting it out there to check the oil level...
 
Did you empty the sump before you did the work? Sounds daft, but if you filled the engine oil on top of an already full sump the engine will be awash with oi which will creep up past the rings. I am sure you are not that daft, just putting it out there to check the oil level...

He has had the sump cover off so i assume the original oil is long gone
 
yes sump cover had been removed! But looking for 'daft' reasons is not a bad idea!!

I recall adding the oil and checking the level on the 'new' dipstick. It was low so I added a couple of pints more.
I am now racking my brain, or what is left of it, to recall the event.

Did I inadvertently pour that oil down the air intake ( the 'filter' head) was not in place and the two holes are close together!! ?

Other possibilities as to how the oil got there seem remote so I am leaning towards a 'daft' senior moment!
So what to do now? Head off or is there another way to get most of that oil out?
 
yes sump cover had been removed! But looking for 'daft' reasons is not a bad idea!!

I recall adding the oil and checking the level on the 'new' dipstick. It was low so I added a couple of pints more.
I am now racking my brain, or what is left of it, to recall the event.

Did I inadvertently pour that oil down the air intake ( the 'filter' head) was not in place and the two holes are close together!! ?

Other possibilities as to how the oil got there seem remote so I am leaning towards a 'daft' senior moment!
So what to do now? Head off or is there another way to get most of that oil out?

It is a diesel, spin it over to get most of it out of the injector hoes, then fit the injectors and fire it up. It will be smoky for a while but otherwise fine. I cannot see any way you could have so much oil in every bore without having poured it in the manifold, or overfilled the sump.
 
It is a diesel, spin it over to get most of it out of the injector hoes, then fit the injectors and fire it up. It will be smoky for a while but otherwise fine. I cannot see any way you could have so much oil in every bore without having poured it in the manifold, or overfilled the sump.

Spinning the engine over should get virtually all of it out ..... but you could always stick a narrow pipe through the injector hole and try to suck any remaining oil out either by mouth or using a manual or electric pump. That should reassure you that you are clear to start the engine without risking any lock-ups, although best to warn your neighbours that there will be a massive stinking oil smoke cloud. :ambivalence:

Richard
 
yes sump cover had been removed! But looking for 'daft' reasons is not a bad idea!!

I recall adding the oil and checking the level on the 'new' dipstick. It was low so I added a couple of pints more.
I am now racking my brain, or what is left of it, to recall the event.

Did I inadvertently pour that oil down the air intake ( the 'filter' head) was not in place and the two holes are close together!! ?

Other possibilities as to how the oil got there seem remote so I am leaning towards a 'daft' senior moment!
So what to do now? Head off or is there another way to get most of that oil out?

I wouldn't go with dipstick markings until I was sure that you had filled the engine with the correct quantity of oil. Adding a 'couple of pints' 'cos it didn't look right isn't the way to go. If the engine requires 8 litres of oil, it will take eight litres.
I suggest draining all the oil and refilling with the recommended amount before trying to start.

Donald
,
 
7 pints/4litres. Engine horizontal on bench. 3 litres added, nothing on dipstick, added the final 2 pints.
The amount which has come out of the injector holes looked a lot but is probably only half a pint.
No evidence of oil in the intake which destroys my 'wrong hole' theory.
My comments about the dipstick arise because I wanted to get the 'correct' measured amount in and then see ( for future reference and topping up) where that level came too on the dip stick.
The 'stick' is new in that it came with an engine that I have not used so I wanted to be sure of it.
Thanks all
 
7 pints/4litres. Engine horizontal on bench. 3 litres added, nothing on dipstick, added the final 2 pints.
The amount which has come out of the injector holes looked a lot but is probably only half a pint.
No evidence of oil in the intake which destroys my 'wrong hole' theory.
My comments about the dipstick arise because I wanted to get the 'correct' measured amount in and then see ( for future reference and topping up) where that level came too on the dip stick.
The 'stick' is new in that it came with an engine that I have not used so I wanted to be sure of it.
Thanks all

So you have overfilled it
Forget the dipstick reading, only add what is stated in the handbook, when the engine is reinstalled THEN check what the DS level is, that will give you a "correct" reading
 
Just a note of caution. diesel engines can and do “run-away” by combusting lube oil in the chamber. I personally would not try to start the engine until you are sure that you do not have a supply of oil finding its way to the combustion chamber.
 
So you have overfilled it
Forget the dipstick reading, only add what is stated in the handbook, when the engine is reinstalled THEN check what the DS level is, that will give you a "correct" reading

Correct , by around a 1/4 pint and, as I said, I wanted to see where this amount came to on the dip stick. It is actually on the low side of the mark even with the extra cup full. I will get the spirit level out!
The point about runaway engines is well made so I will investigate the oil in cylinders further.

Thanks all.
 
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