I'm installing a remote oil filter on my truck. I'm also going to install a bypass filter and send away regular oil samples to determine when I actually need to change my oil, not just some nice round number that makes me feel good. I'm wondering if it would be possible to install an oil pressure gauge before and after the remote oil filter, and use the pressure difference to determine when it is actually time to change the filter?
Oil pressure gauge to determine filter change time
- Thread starter OilFilters
- Start date
- Status
A bypass filter is going to have full oil pressure at the inlet, and ZERO at the outlet (which returns to the sump). IMHO, best way to evaluate the bypass is to put the return line somewhere easy to remove & check the flow (like an oil filler cap).
I'm not talking about the bypass filter, I'm asking about the main full flow filter. It's going to be remote also.
Yes. Change the oil filter when the pressure difference gets to 50% more than when the oil filter was new, warm engine at 2,000 RPM. This kind of thing is done with air filters to determine clogging, should work fine for oil filters.
Check my answer with Jay Buckley with Fram, as he can ask engineers there to be sure.
Also ask him if its actually better to run a dual parallel oil filter setup, like a bypass oil filter right next to a normal oil filter, where all the flow goes to the engine. With that, maybe 5% will go through the bypass filter (not actually bypassing the engine though!!).
Jay's handle name is often MotorKing, and I can't find his email address right now.
Also PM him here on bitog just in case.
Also ask him if its actually better to run a dual parallel oil filter setup, like a bypass oil filter right next to a normal oil filter, where all the flow goes to the engine. With that, maybe 5% will go through the bypass filter (not actually bypassing the engine though!!).
Jay's handle name is often MotorKing, and I can't find his email address right now.
Also PM him here on bitog just in case.
Jay Buckley at [email protected]
and PM Motorking in case he monitors that anymore.
and PM Motorking in case he monitors that anymore.
dnewton3
Staff member
Jim Allen was experimenting with this very concept. He was collecting some really good data. But he's been gone a while now. I will say the equipment he had was very pricey.
Also, the decision you'd have to make is at what dP would you be driven to FCI? For example, if you had a FF filter that was set to crack open at 9psi, then perhaps you'd change at a steady 8psi? That would give you about 12% safety margin for the assured variance of each filter you purchase; not all of them are going open exactly at 9psi ...
The real problem you'd have is that you'd have a VERY hard time actually telling when the BP valve was opening towards the end of the filter life.
Jim's data showed that the BP burped open VERY infrequently, and only under cold start combined with WOT blips. Otherwise, the BP essentially is a safe guard that (thankfully) is rarely engaged. His filter had a 9-11psi (crack open to full open) range. But his running dP over the filters was only 2-4 psi. So he never came close to loading the filter up.
But as you experiment with loading the media, you're closing that gap. You're going to trying to operate around 6-8psi. And once you get to around 8-psi, you have to ASSUME that you're not really letting come BP sneak by. Because of a lot of variables (OEM spec ranges, your gage variance, et), you'll not REALLY know EXACTLY when the BP is going to open. It make pop open, then close, then open, then close ... who knows? Or, if you're close to the edge, it may open and stay cracked open, and you'll not know you're in BP because the dP is possibly going to remain in your pre-determined safe range?
This concept works well when there's a fairly large dP range. It's much more tricky when you're trying to get "close" to the BP event, without going over the edge.
Also, be prepared to FCI at a moment's notice. Once the media loads up near it's full capacity, the loading is exponential and not linear.
Although you're talking about oil filters, the same applies to air filters.
See this air-filter-minder page about loading ...
www.filterminder.com
see the second tab over on the lead page; talks about the loading frequency.
So my point is that once you decide to ride close to the limit (presuming you're trying to maximize the filter ROI), then you are also running very close to going over the edge. And that line comes up VERY quickly.
Also, the decision you'd have to make is at what dP would you be driven to FCI? For example, if you had a FF filter that was set to crack open at 9psi, then perhaps you'd change at a steady 8psi? That would give you about 12% safety margin for the assured variance of each filter you purchase; not all of them are going open exactly at 9psi ...
The real problem you'd have is that you'd have a VERY hard time actually telling when the BP valve was opening towards the end of the filter life.
Jim's data showed that the BP burped open VERY infrequently, and only under cold start combined with WOT blips. Otherwise, the BP essentially is a safe guard that (thankfully) is rarely engaged. His filter had a 9-11psi (crack open to full open) range. But his running dP over the filters was only 2-4 psi. So he never came close to loading the filter up.
But as you experiment with loading the media, you're closing that gap. You're going to trying to operate around 6-8psi. And once you get to around 8-psi, you have to ASSUME that you're not really letting come BP sneak by. Because of a lot of variables (OEM spec ranges, your gage variance, et), you'll not REALLY know EXACTLY when the BP is going to open. It make pop open, then close, then open, then close ... who knows? Or, if you're close to the edge, it may open and stay cracked open, and you'll not know you're in BP because the dP is possibly going to remain in your pre-determined safe range?
This concept works well when there's a fairly large dP range. It's much more tricky when you're trying to get "close" to the BP event, without going over the edge.
Also, be prepared to FCI at a moment's notice. Once the media loads up near it's full capacity, the loading is exponential and not linear.
Although you're talking about oil filters, the same applies to air filters.
See this air-filter-minder page about loading ...
www.filterminder.com
see the second tab over on the lead page; talks about the loading frequency.
So my point is that once you decide to ride close to the limit (presuming you're trying to maximize the filter ROI), then you are also running very close to going over the edge. And that line comes up VERY quickly.
Last edited:
A bypass filter does not have a bypass, all the oil has to go through it. On my old '69 F1000 Ford truck I used my hand to tell me when to change the bypass filter. When the filter did not get hot or took longer to get hot I'd change it out. If oil can't get through it, it won't get hot.
Not very scientific but that old Cummins 335 had over two million miles on it.
ROD
Not very scientific but that old Cummins 335 had over two million miles on it.
ROD
Originally Posted By: dnewton3
Also, the decision you'd have to make is at what dP would you be driven to FCI? For example, if you had a FF filter that was set to crack open at 9psi, then perhaps you'd change at a steady 8psi? That would give you about 12% safety margin for the assured variance of each filter you purchase; not all of them are going open exactly at 9psi ...
Not a good idea to get that close to the bypass valve setting when checking differential pressure at 2,000 rpm on a hot engine. Remember cold viscous oil is going to create even higher differential pressure, meaning bypass happens way to often if you're 12%-close hot.
Using the bypass pressure spec could be wise though. I'd allow up to 40% of the margin between new filter differential pressure and the bypass spec to be encroached upon (again, 2k rpm hot) before changing the filter. Fram engineers would have a more exact answer.
Also, the decision you'd have to make is at what dP would you be driven to FCI? For example, if you had a FF filter that was set to crack open at 9psi, then perhaps you'd change at a steady 8psi? That would give you about 12% safety margin for the assured variance of each filter you purchase; not all of them are going open exactly at 9psi ...
Not a good idea to get that close to the bypass valve setting when checking differential pressure at 2,000 rpm on a hot engine. Remember cold viscous oil is going to create even higher differential pressure, meaning bypass happens way to often if you're 12%-close hot.
Using the bypass pressure spec could be wise though. I'd allow up to 40% of the margin between new filter differential pressure and the bypass spec to be encroached upon (again, 2k rpm hot) before changing the filter. Fram engineers would have a more exact answer.
- Status
Similar threads
- Locked