Lombardini engine woes !

[phil5]

Hi all ............ looking for help/suggestions/past experiences regarding my Lombardini LDW 903 engine

 The problem I have is oil getting into the air filter box.

I've cleaned the breathers which are part of the rocker box & diverted the flow into an oil catch can. Nothing appears to be going into the can, but oil is still appearing in the air filter box.

 The only other way I can see for oil to get in there, is by getting by the piston rings, into the combustion chamber, then through the inlet valves. I can't see that this is happening as it would surely result in rough running and a smokey exhaust, neither of which I have.

 Any help out there ? 

[mrsmelly]

18 minutes ago, phil5 said:

Hi all ............ looking for help/suggestions/past experiences regarding my Lombardini LDW 903 engine

 The problem I have is oil getting into the air filter box.

I've cleaned the breathers which are part of the rocker box & diverted the flow into an oil catch can. Nothing appears to be going into the can, but oil is still appearing in the air filter box.

 The only other way I can see for oil to get in there, is by getting by the piston rings, into the combustion chamber, then through the inlet valves. I can't see that this is happening as it would surely result in rough running and a smokey exhaust, neither of which I have.

 Any help out there ? 

Whilst I am no mechanic. Cars I have owned from the 1920s to around the 1980s often had this problem when they had a few miles on their backs. I believe it is down to bore/piston/valve stem etc wear. The old for crossflow jobbies of the 60s/70s were renowned for it.

[rusty69]

2 minutes ago, mrsmelly said:

Cars I have owned from the 1920s

Blimey mrsmelly, I knew you was old, but didn't think you was ancient

[mrsmelly]

5 minutes ago, rusty69 said:

Blimey mrsmelly, I knew you was old, but didn't think you was ancient

It wasn't a mistake. I used to collect old cars and at one time had 23. One of my faves was a pre flying Standard of 1928. I have owned others from the 30s upwards.

[dccruiser]

26 minutes ago, phil5 said:

Hi all ............ looking for help/suggestions/past experiences regarding my Lombardini LDW 903 engine

 The problem I have is oil getting into the air filter box.

I've cleaned the breathers which are part of the rocker box & diverted the flow into an oil catch can. Nothing appears to be going into the can, but oil is still appearing in the air filter box.

 The only other way I can see for oil to get in there, is by getting by the piston rings, into the combustion chamber, then through the inlet valves. I can't see that this is happening as it would surely result in rough running and a smokey exhaust, neither of which I have.

 Any help out there ? 

Bit of a strange one , the engine is obviously pressurising its just what route that pressure is taking to get oil into the air cleaner ... if it isnt via the breathers and the pressure isnt in the crankcase the only other way i can figure is via the valve stem seals or the valve seats themselves the only way of checking further is with a compression tester ... if your anywhere near the midlands i have one   

Rick 

[X Alan W]

16 minutes ago, dccruiser said:

Bit of a strange one , the engine is obviously pressurising its just what route that pressure is taking to get oil into the air cleaner ... if it isnt via the breathers and the pressure isnt in the crankcase the only other way i can figure is via the valve stem seals or the valve seats themselves the only way of checking further is with a compression tester ... if your anywhere near the midlands i have one   

Rick 

I would have thought if the inlet valve seal were worn/faulty the Suck of the Suck/Sqeeze/Bang /Blowset up would draw the oil along with the air into the cylinders if the valves were seating poorly compression would suffer is it possible to run the motor without the rocker /valve cover to see if there is any signs of blow by or any thing unusual.

[dccruiser]

7 minutes ago, X Alan W said:

I would have thought if the inlet valve seal were worn/faulty the Suck of the Suck/Sqeeze/Bang /Blowset up would draw the oil along with the air into the cylinders if the valves were seating poorly compression would suffer is it possible to run the motor without the rocker /valve cover to see if there is any signs of blow by or any thing unusual.

I agree to a certain extent was just thinking along the lines of a bike pump where a valve closing can make the seal and as it opens it releases pressure ... obviously its purely speculative on the information given ... and makes assumptions the pressure is top end rather than sump and coming up the oil feeds in which case i would expect the breathers to do their job if they have been cleared and showing no signs of oil.

 

Rick

[smiler]

Maybe teaching granny how to suck eggs - but did you check for blockages in any hoses connected to the breathers?

[miq]

I had this problem with my Lombardini engine for over 10 years and never solved it! The engine was stripped and rebuilt, by a competent fitter without any problem being found. The Lombardini agent whom I consulted and who had previously been involved in Lombardini engine renovations, had nothing to add, and in the end I removed the diaphragm unit and connected the engine breather pipe on the rocker cover direct to the air filter housing and did as you have done and diverted the 'overflow' into a container which I emptied periodically. The paper filter had to be removed and the filter housing left empty, but the engine space on a narrowboat is not a particularly hostile environment and a bit of crumpled stainless steel netting in the air intake tube prevented the possibility of any large stray items like leaves from entering the engine. The engine continued to run for some years and was still in good running order when I sold it.

[Tony Brooks]

1 hour ago, X Alan W said:

I would have thought if the inlet valve seal were worn/faulty the Suck of the Suck/Sqeeze/Bang /Blowset up would draw the oil along with the air into the cylinders if the valves were seating poorly compression would suffer is it possible to run the motor without the rocker /valve cover to see if there is any signs of blow by or any thing unusual.

You do get pressure pulses bouncing back down the inlet tract as the valves close and the inertia; in incoming air compresses it against the valve so it then "bounces/blows" back. I am not saying this is what is happening but its possible.

Can't help with the problem though, I go with Miq. Just throw the filter away.

[phil5]

Thanks for all the replies so far .......... some interesting thoughts & things to look at

One other thing that I have wondered about ............ down on the block, according to the manual, there is a pressure regulator - could that possibly be faulty, causing to high a pressure to be built up in the crankcase ? I'd guess there's no way of checking it & a replacement would be the way to go.

 

22 hours ago, miq said:

I had this problem with my Lombardini engine for over 10 years and never solved it! The engine was stripped and rebuilt, by a competent fitter without any problem being found. The Lombardini agent whom I consulted and who had previously been involved in Lombardini engine renovations, had nothing to add, and in the end I removed the diaphragm unit and connected the engine breather pipe on the rocker cover direct to the air filter housing and did as you have done and diverted the 'overflow' into a container which I emptied periodically. The paper filter had to be removed and the filter housing left empty, but the engine space on a narrowboat is not a particularly hostile environment and a bit of crumpled stainless steel netting in the air intake tube prevented the possibility of any large stray items like leaves from entering the engine. The engine continued to run for some years and was still in good running order when I sold it.

Thanks miq ............. obviously I didn't want to hear that !! Lol !

 So if your catch can was filling up, did it stop any flow into the air filter housing ? My catch can remains empty, but oil's still finding it's way into the AFH.

 My main concern with this problem is diesel run-on .......... where the oil starts to fuel the engine and it 'runs-away' with itself leading to eventual destruction. And apparently there's no way of stopping it !

 Otherwise, the engine runs fine with plenty of power & not smokey. 

[Tony Brooks]

2 minutes ago, phil5 said:

Thanks for all the replies so far .......... some interesting thoughts & things to look at

One other thing that I have wondered about ............ down on the block, according to the manual, there is a pressure regulator - could that possibly be faulty, causing to high a pressure to be built up in the crankcase ? I'd guess there's no way of checking it & a replacement would be the way to go.

 

Thanks miq ............. obviously I didn't want to hear that !! Lol !

 So if your catch can was filling up, did it stop any flow into the air filter housing ? My catch can remains empty, but oil's still finding it's way into the AFH.

 My main concern with this problem is diesel run-on .......... where the oil starts to fuel the engine and it 'runs-away' with itself leading to eventual destruction. And apparently there's no way of stopping it !

 Otherwise, the engine runs fine with plenty of power & not smokey. 

If its related to the breather system then yes, if say the fuel system or oil system then no.

I think a photo of this device or info about what its connected to may help.

[phil5]

Unfortunately I can't upload photos at the moment.

The pressure regulator is connected to the oil system. If it was faulty I'm guessing it could allow the oil pressure tobe too high, thereby forcing oil where it wouldn't normally go ?!!

[Tony Brooks]

If its the oil pressure relief valve by a "translated" name then yes, it could allow the engine oil [pressure to go high but they rarely fail in that mode. (in general, not Lombardini specific).  They usually fail open and that give slow oil pressure.

Any high oil pressure is only in the oil pipes and galleries inside the engine so apart from a possible oil leak from the cylinder head gasket where the rocker/cam shaft oil feed passes into the head high oil pressure is unlikely to cause external leaks.

If the Lombardini uses oil jet lubrication for the small end neraings then iyt just might allow excess oil to get onto the cylinder wall with high oil pressure but in my view a split oil filter would be a much more likely symptom.