Here you go Chilly this may help. https://www.duramaxdiesels.com/forum/threads/oil-pump-conversion-info.42505/
Low oil pressure on new build using LML/L5P oiling parts
- Thread starter Chilly
- Start date
Not by any means on the Banks band wagon but I did just see his Monster truck dyno video and he mentions using the bigger nozzles and them having to use a “Wide Gear Oil Pump” whatever that is to keep the oil pressure up when using them.
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banks made their own higher volume pump that is larger than the LML/L5P. it is not for sale.
Unless you open up the bottom end and start looking for the issue, its all guessing game.
Unless you open up the bottom end and start looking for the issue, its all guessing game.
I guess I could chime in on this one.. I was just showing the banks video to my GM tech buddy yesterday. He's the one who came up with the idea to modify the LML pumps we use in the marine engines. We got a good laugh out of it, cause we started running that setup over 4yrs ago. But felt good to see our work verified by him.
First, I hope your checking pressure with a manual gauge and not going by the dash. I've played with the LBZ/LMM ECM enough on the bench to know GM pads the output below 35psi, that I would verify anything I questioned with a manual gauge. I've actually used a variable resistor in place of OEM sensor and scaled it top to bottom. Below like 35, GM will show you 30, when it might only be 15psi.. It's padded in the ECM code, and I suspect due to the oil squirters spring and ball closing in that same area. Also there was an issue with sensor wire chafing at the connector on valve cover that will screw with the gauge. Noted my experince with that somewhere on here many years ago.
Before the LML squirter mod, we used to drill the tube tips out on older stuff. Never noted any issue with pressure using an old style pump and that trick. However, refer to paragraph above.. That said, I've only used LML squirters with a LML pump. And those pumps get shimmed up to where we make about 100PSI cold oil pressure above 1500R. Now that I've put about 80hrs on these two engines, they have fallen off from 60psi to holding 35-40 at HOT idle. I don't have a manual gauge either, but do have an old school oil pressure switch in the setup that controls lift pumps and pops an oil light on dash if they drop under 25psi. So far no light at idle, so engines and me remains happy.
I can't speak for any aftermarket pumps, but everyone and their brother has tried to sell me their version. The main reason we chose to run the LML pump was the pickup tube and obvious thicker gears means more volume potential. Popped a couple swashers under the bypass spring for good measure and, and questioned that upon first firing.. But now, glad we did because they hold 80-100psi above 2000rmp. With the LML, GM changed to that whole setup for a reason. Only other noted oiling change was the squirter size. So you have to ask, why did GM make those upgrade??
Personally I don't believe your issue would be the squirters because of the check ball setup. If you are dropping under 25psi, those are not passing any oil and thus not the issue.. Just my 2c however.
First, I hope your checking pressure with a manual gauge and not going by the dash. I've played with the LBZ/LMM ECM enough on the bench to know GM pads the output below 35psi, that I would verify anything I questioned with a manual gauge. I've actually used a variable resistor in place of OEM sensor and scaled it top to bottom. Below like 35, GM will show you 30, when it might only be 15psi.. It's padded in the ECM code, and I suspect due to the oil squirters spring and ball closing in that same area. Also there was an issue with sensor wire chafing at the connector on valve cover that will screw with the gauge. Noted my experince with that somewhere on here many years ago.
Before the LML squirter mod, we used to drill the tube tips out on older stuff. Never noted any issue with pressure using an old style pump and that trick. However, refer to paragraph above.. That said, I've only used LML squirters with a LML pump. And those pumps get shimmed up to where we make about 100PSI cold oil pressure above 1500R. Now that I've put about 80hrs on these two engines, they have fallen off from 60psi to holding 35-40 at HOT idle. I don't have a manual gauge either, but do have an old school oil pressure switch in the setup that controls lift pumps and pops an oil light on dash if they drop under 25psi. So far no light at idle, so engines and me remains happy.
I can't speak for any aftermarket pumps, but everyone and their brother has tried to sell me their version. The main reason we chose to run the LML pump was the pickup tube and obvious thicker gears means more volume potential. Popped a couple swashers under the bypass spring for good measure and, and questioned that upon first firing.. But now, glad we did because they hold 80-100psi above 2000rmp. With the LML, GM changed to that whole setup for a reason. Only other noted oiling change was the squirter size. So you have to ask, why did GM make those upgrade??
Personally I don't believe your issue would be the squirters because of the check ball setup. If you are dropping under 25psi, those are not passing any oil and thus not the issue.. Just my 2c however.
Removing the sandwich adapter fixed low pressure issues for us on 2 LML's with 2020 coolers. I have not had a chance to figure out why. If customer needs more cooling, we put a small cooler up front with -4 line and drain into filler neck. Has worked well for our hotshot guys.
For the people that had trouble with the sandwich adapter are you using the mocal adapter with at least -12 lines?
This one on page 5 on the link below
SP2TC Billet Thermostatic Sandwich Plate
This is what I used and have no problems.
Edit: Not sure if it will work on the 2020 cooler/filter header assembly though.
This one on page 5 on the link below
SP2TC Billet Thermostatic Sandwich Plate
This is what I used and have no problems.
Edit: Not sure if it will work on the 2020 cooler/filter header assembly though.
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Removed sandwhich plate and adapter for 2020 cooler.
Oil pressure has come up tremendously!
Oil temp and pressure was around 180/39PSI at 2000RPM and wouldn’t budge one bit above 40 PSI. Cooler removed I am now seeing around 195/55-60PSI at around 2000RPM. My only conclusion is that it was a combination between a poor flowing cooler and the sandwhich plate leaking flow somewhere. I originally by-passed cooler ONLY and did see a slight increase in pressure but not enough.
Removed everything and am quite happy with the results.
I still plan to drop the 15w-40 for 20W50. Keeping aux cooler off for good!
Something was just weird with that adapter plate. As soon as oil pressure hit 40PSI it’s like the pump just hit a wall. Even though I had another 1500-2000RPM to turn.
Oil pressure has come up tremendously!
Oil temp and pressure was around 180/39PSI at 2000RPM and wouldn’t budge one bit above 40 PSI. Cooler removed I am now seeing around 195/55-60PSI at around 2000RPM. My only conclusion is that it was a combination between a poor flowing cooler and the sandwhich plate leaking flow somewhere. I originally by-passed cooler ONLY and did see a slight increase in pressure but not enough.
Removed everything and am quite happy with the results.
I still plan to drop the 15w-40 for 20W50. Keeping aux cooler off for good!
Something was just weird with that adapter plate. As soon as oil pressure hit 40PSI it’s like the pump just hit a wall. Even though I had another 1500-2000RPM to turn.
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His engines also are in a boat that sees a ton of sustained high RPM. An oil pressure drop is not uncommon on a fresh motor as everything settles in.
Gotcha, on the boat part.
I’ve built a lot of engines. Stock all the way to heavily modified. Never built a diesel though. I’ve never seen a 20 psi drop in oil pressure just from “break in”. Not even 5 psi, actually, but I digress.