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Zeusmotorworks

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@full-race geoff

Is the Melling M390HV Oil Pump really an upgrade? I've heard of people using it, but don't know if it offers more than just more oil pressure. Or I should say, I've not heard if the design itself is more robust or just a spring pressure change.
 
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full-race geoff

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A Gen2 oil pump is a crescent design with vanes on the gear and a spring on the crescent lever. The crescent has 2 modes. The system operates in "high oil pressure mode" most of the time.

This changes when the engine is fully up to temp and at idle or very light load it decides to save fuel, the ECM sends a 12V signal that switches the solenoid to rotate the crescent mechanism into "low oil pressure mode". This brings oil pressure all the way down to 20-24psi even at 2200rpm (!!!). That is simply not enough oil pressure for a high performance twin turbo raptor engine IMHO ... and this happens OFTEN.


The purpose is to improve fuel consumption by reduction of pumping losses. If the +12V signal wire is damaged or solenoid not extending, the oil pump has a spring on the crescent lever to stay in high oil pressure mode. But if the solenoid gets stuck in the extended position the oil pump will get stuck in low pressure mode.
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I don’t know about you but this low pressure mode and complicated oil pump gives me heartburn. At this point I've seen enough and want to remove the solenoid and its low pressure mode in their entirety. Converting to a traditional and more reliable oil pump is necessary to achieve my objective

Is the Melling M390HV Oil Pump really an upgrade? I've heard of people using it, but don't know if it offers more than just more oil pressure. Or I should say, I've not heard if the design itself is more robust or just a spring pressure change.

-> Have you truly heard of people using the M390HV on a Gen2 Raptor engine?? I can not find any evidence of this although it seems like "an upgrade" in that it removes the solenoid and the crescent/vane pack. I plan to spend time on trying this over the next couple of weeks. I have oil-pickup and p06da mil questions for anyone thats actually tried it already! here is my understanding:

1/ The M390HV is Melling's $150 pump for Ford's Generation 1 3.5L Ecoboost and comes with a stiff spring rate installed. They also supply a softer spring rate that IMO should be utilized in all 3.5L installations This is an interesting pump because it uses a traditional Gerotor oil pump design that is thicker/wider than OEM and a traditional pressure relief. I consider it to be more reliable. Is the gear the same powder metal as Ford OEM? (I think so). I have some spare pumps to sacrifice for science

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2/ The M490 is Melling's $350 pump for Ford's Gen 2 and Gen3 3.5L Ecoboost. Melling claims to upgrade the M490 to a stainless steel gear, I doubt that and will confirm my suspicions shortly. I’ve seen one user have the melling solenoid fail 850 miles after install. From what Ive seen the Melling is quite literally the identical tooling casting as OEM ford, but with the fomoco logos removed with a grinder. you can see the grinder marks in their photos below.

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Zeusmotorworks

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-> Have you truly heard of people using the M390HV on a Gen2 Raptor engine?? I can not find any evidence of this although it seems like it may be "an upgrade" in that it removes the solenoid and the crescent/vane pack. I plan to spend time on trying this over the next couple of weeks. I have oil-pickup and p06da mil questions for anyone thats actually tried it already! here is my understanding:
In retrospect I cannot say for sure it was Gen 2 motors. Back when I first decided to "settle" for an ecoboost raptor, did a lot of reading on the F150 forums. In following your thread, I had remembered saving the link to that pump. I have not found a link to that thread yet. The reason I asked.
 
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full-race geoff

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I kept at it and found the little gremlin. Here is the failure prone oil pump solenoid. It gets stuck in the low pressure mode:

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Here is the solenoid internals, you can see the second item is the internal piston that’s getting stuck

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Closeup to show scuffing as it got binded up in the bore and sticking on low pressure mode. I would switch 12V over and over and often times the solenoid would be stuck extended (low pressure mode). After I disassembled, cleaned and reassembled it was moving much better and not sticking, but I could still get it to stick once in a while.

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@Zeusmotorworks I have to say thank you. Checking the Gen2 block with the non variable Gen 1 oil pump + pickup earlier today and IT WORKS. This is the start of the solution I’m looking for
 
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Zeusmotorworks

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I swear someone else had done it before. However, at this age/mileage I just can't remember which forum. However, if it works and helps people here, all the better.
 
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full-race geoff

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Yukons 4.88s are installed in the Gen 3 rear axle, and rear suspension is ready to go.

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No ebrake for now- the 2017 cable ebrake is not useable on the gen3 axle. The 2018+ EPB (electric parking brake) remains here and I’d love to use the Mustang/RTR drift brake ‘PEPB’ though that can all wait.

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Gen 1 (blue), Gen 2 (red), Gen 3 (black) - it’s incredible how many similarities there are across the lineage, and how many improvements are present in the Gen 3.

After a busy few days - here’s where I’m at on the oil pump topic: a serious engine needs a strong oil pump. Just like a serious athlete needs a strong heart. Here’s an example of what an oil pump gear should look like for a $15-20k engine build

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VS the Gen 2/3 oil pump…

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Therefore the one part that irks me on the Gen 3 is it uses the same Gen 2 oil pump. This is an expensive over complicated engineering atrocity with weaknesses everywhere you look. Yes it can eek out 0.1mpg and it can also fail spectacularly
 

letsgetthisdone

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There is nothing wrong with the vane style oil pump. Its actually how a lot of hydraulic pumps, including power steering pumps, are built. They can flow a lot with very high pressures (3000-4000psi) and are highly reliable as long as the fluid they are pumping stays (relatively) clean (power steering pumps fail because no one ever changes that fluid).

The issues arise with the variable geometry/pressure system. A lot of manufacturers have moved to that and of course the 1st generation of anything has it's issues. BMW for example, their oil pumps are fully variable, as opposed to Ford's more simple hi/lo only system, and BMW had issues with the variable oil pump in the Gen1 B58's. For the hi/lo switchover in our trucks, you can go into the tune and change when the pump switches over. In HPTuner it's a (IIRC) 3D table with RPM and load on the axis. I never bothered to mess with it other trying to see if the Ford tuned it to be basically on/off, but it was actaully a PWM output so I could get the oil pressure up a bit for cruise. It's not a PWM output on the ECU so we're stuck with on/off, so I left the table the stock becuase I got oil pressure codes when trying to adjust the target and the "duty cycle" to an "in the middle" value.

So, I would not hesitate to run the vane pump with the variable displacement stuff disabled/locked out.
 
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