Hi,
I have two questions about oil and filters in our Fulvia's.
First about the filters. The Fulvia I recently bought has a MANN filter type w940/1 in it, this has been fitted by the previous owner. This part cross references with the filter type known by the Viva Lancia community W940/25. The filters all have 'flowback valves' in them and I found out the differences lie in the opening pressure to open the valve which is 1,2 bar for the W940/1 and 2,5 bar for the W940/25, quite a difference. This pressure of 2,5 bar is more or less the same for all the suitable oil filters from other brands named in the Q and A section. Does anyone know what this number indicates?
Second about oil. What is your experience with mineral oils in Fulvia engines? I decided to go for an oil type from Eni, I-sint 20w50 classic API SF. The name suggests synthetic oil however it is mineral.
Oil related questions
Re: Oil related questions
To deal with the second question, I have found (finally) this old thread which I have not seen before:
http://www.viva-lancia.com/lancia_fora/ ... 1#msg-4391
Since my strategy is change oil and filter often I have a good feeling about mineral oil.
http://www.viva-lancia.com/lancia_fora/ ... 1#msg-4391
Since my strategy is change oil and filter often I have a good feeling about mineral oil.
Re: Oil related questions
That is some time ago.
In our shop we now use Millers full synthetic 10W60 with 3 esthers and NT (nano technology) in rebuilt engines right from kilometer zero. That will keep the engine in top condition for at least 300.000 km. Excellent oil pressure and no oil consumption. Of course we make sure the inginition is never earlier than specified. Oil change every 30.000 km.
If a car comes in with an engine that has been running on mineral for some time we still use the 20W50 or 15W40 and change more frequently.
In our shop we now use Millers full synthetic 10W60 with 3 esthers and NT (nano technology) in rebuilt engines right from kilometer zero. That will keep the engine in top condition for at least 300.000 km. Excellent oil pressure and no oil consumption. Of course we make sure the inginition is never earlier than specified. Oil change every 30.000 km.
If a car comes in with an engine that has been running on mineral for some time we still use the 20W50 or 15W40 and change more frequently.
Re: Oil related questions
Ok, good to know. The car has run 98.000km and current oil is also mineral 20w50 SF.
Any idea what the bypass valve in the filter does? Is this may be to make the oil flow passed the filter in case its clogged?
Any idea what the bypass valve in the filter does? Is this may be to make the oil flow passed the filter in case its clogged?
Re: Oil related questions
The bypass valve opens to prevent oil starvation of the engine. As you say the filter may be clogged. Or when the oil is still cold not enough may pass through.
If you Google on the bypass valve, you find plenty. Try to read more than one article. When you have read them all, still keep an open mind.
If we neglect the internal leakage of the oil pump, the Fulvia oil pump is a pump that pumps a fixed volume per revolution. The oil pressure is the "back pressure" as determined at the receiving end. The sum of all the clearances at the bearings etc and the viscosity of the oil determine oil pressure. Theoretically the pressure could go up to infinity if nothing breaks and the engine has unlimited power.
However, there is another by pass valve just before the oil filter where the oil arrives from the pump. That valves opens at 6 bar and bleeds excessive oil back to the sump.
If you Google on the bypass valve, you find plenty. Try to read more than one article. When you have read them all, still keep an open mind.
If we neglect the internal leakage of the oil pump, the Fulvia oil pump is a pump that pumps a fixed volume per revolution. The oil pressure is the "back pressure" as determined at the receiving end. The sum of all the clearances at the bearings etc and the viscosity of the oil determine oil pressure. Theoretically the pressure could go up to infinity if nothing breaks and the engine has unlimited power.
However, there is another by pass valve just before the oil filter where the oil arrives from the pump. That valves opens at 6 bar and bleeds excessive oil back to the sump.
Re: Oil related questions
I've read some articles and not all state the same so it can be confusing.
May I conclude it is quite likely that the oil filter is bypassed right after start up?
I am not sure if it makes a big difference but I am trying to figure out what the difference between 1,2 bar and 2,5 bar means in practical terms.
Nevertheless I am keen on proper engine maintenance so the oil and filter need to be refreshed!
May I conclude it is quite likely that the oil filter is bypassed right after start up?
I am not sure if it makes a big difference but I am trying to figure out what the difference between 1,2 bar and 2,5 bar means in practical terms.
Nevertheless I am keen on proper engine maintenance so the oil and filter need to be refreshed!
Re: Oil related questions
There are so many questions unanswered for your particular situation and even if you would have the answers they change with temperature and probably a whole lot more.
Many years ago I asked my oil filter supplier to supply me with oil filters equivalent to the Lancia listed number I gave him. He came up with the MANN W940/1 which I used since then.
Many years ago I asked my oil filter supplier to supply me with oil filters equivalent to the Lancia listed number I gave him. He came up with the MANN W940/1 which I used since then.