Oil filter has no bypass valve

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DiyNutJob

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Got a bosch P2060 / 0986452060 filter from ebay for use on a micra. Both the filter and box look OK, but the filter doesn't appear to have a bypass valve, which I find could be unusual. As I have no experience of these filters, wondering if anyone knows this is normal? Or, do I have a fake product?

At the bottom of the filter element is a dome shaped recess for encasing the spring at the bottom of the can. Normally the valve would be in the middle of the dome. There's nothing at the top of the filter to suggest the valve is there either. Around the dome, there is just glue for fixing the filter media in place.

filter2.png
filter1.png
 
That's the filter anti-drain filter, I think.....it depends on the filter orientation whether it's necessary. Perhaps it's a filter that fits several cars as well as the Micra.
I'd like to fit one that is exactly the same, as it has to re-fill if drained and the oil light takes a few seconds to go out.
John :)
 
The bypass valve is for when the media is blocked by debris. It is also for when oil is cold and doesn't flow through the media easily. This valve is not same as the rubber seal behind the holes. The seal is for keeping oil in the filter. In all the videos of oil filters, there is a bypass valve.
 
Fair enough - I haven't made a study of them but I do buy filters that I can trust to be the same as OE.
The bypass is often in the oil pump or the filter housing - but hopefully the filter would never be allowed to block anyway. Eco paper cartridge filters have to use this method.
John :)
 
The bypass valve is in all american filters. So it seems unlikely the valve would be in the engine rather than in the filter. It could be an american thing because they are very obsessed with the filter. I am just curious if it's normal to not have a valve. The bosch literature suggests a valve.

 
All engines have an oil pressure relief valve, but that's completely separate to the one in the filter. As has been said, the one in the filter is only for when the element is too clogged for the oil to get through - on the assumption that dirty oil is better than no oil at all. I don't know what's in the current Bosch filters, but I've seen various different ways of doing it. Some cheaper ones seem to have a simple spring where the whole element is just pushed off its seat when they operate. I tend to prefer Mahle and Mann filters over Bosch these days, but that's just a personal preference.
 
The large spring at the bottom of the can serves to press the filter element against the base plate for a permanent seal. Unlikely to impossible oil pressure will open that seal. The spring on the bypass valve is small and weak. I am fairly sure there is no valve in this filter. Since I have no point of reference, I can't tell if that's normal. I guess people in the UK don't look before using their filter. I will use the filter for extended service, and minor details like this does matter. If nissan filters have no valves for the UK, I won't need the valve either. I might be able to get a half a confirmation from the existing filter when I take it out. But it's likely to be a cheap generic put in by the local garage. I know they use cheap tires as I see one on the car.

These days I use the cheapest with some confirmed quality that works. I got the bosch one cheaper than anything else. I use mann can-less filter for my car. That's confirmed good for 10+ years. I will stick with that simply because I don't want to spend another 10 years testing something else. The micra is new experience for me. So, I can do tests on it and forgo the more expensive canned mann filter. There's no guarantee there is a valve in that either.
 
The spring rate on its own, is irrelevant unless you know the area over which the pressure is acting. 40PSI of oil pressure acting on the whole top surface of a 3" diameter filter element will produce about 300 lb of "push"...

It's not something that concerns me hugely, but then, I don't try to keep the same oil and filter for 10 years, so it's unlikely to get clogged in the first place...
 
If in doubt, buy a main dealer one - they aren't expensive and then you know it's correct. Who knows what has been fitted in the past?
John :)
 
The bypass valve opens on light pressure. If something opens on high pressure, then it's not really a bypass valve. It would be an anti-burst valve.
 
Burnerman said:
If in doubt, buy a main dealer one - they aren't expensive and then you know it's correct. Who knows what has been fitted in the past?
John :)
Click to expand...

I might have done that if I knew it was this complicated. Now that I already have the filter, I will run with it. Asking questions is free. I am OK to deal with the unknown. But, seriously, not one single person in the UK knows the can filters have valves in them?!!!
 
DiyNutJob said:
The bypass valve opens on light pressure. If something opens on high pressure, then it's not really a bypass valve. It would be an anti-burst valve.
Click to expand...
What do you consider to be low and high pressure?
The bypass valve was factory set so that the original paper filter doesn't burst......highly unlikely anyway since we did away with the 20/50 multigrades. The pressure was set higher once OHC engines came along.
John :)
 
Poking the valve open with finger would be light pressure. Deforming this piece would be high pressure:

spring.png
 
DiyNutJob said:
The bypass valve opens on light pressure. If something opens on high pressure, then it's not really a bypass valve. It would be an anti-burst valve.
Click to expand...
I'm not sure you actually understand the concept of "pressure"? You can hold back 1000 PSI with your little finger, if it's acting over a small enough area, whereas you won't be able to hold back even 100 PSI with your whole hand over a larger area.

The bypass valve (if fitted) will open when the pressure differential across the element reaches a value that the manufacturer reckons would be likely to cause some damage.
 
DiyNutJob said:
... But, seriously, not one single person in the UK knows the can filters have valves in them?!!!
Click to expand...

I would have thought the fact that you're here, discussing valves in oil filters with at least two people in the UK, suggests that you're wrong in that assertion...:rolleyes:
 
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