OM612 low oil pressure - Oil Pump Info
- Thread starter AdrianD
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Re: OM612 low oil pressure when hot
And for a short time in the good ole' US of A. Added. Nope.
The Jeep OM612 diesel had an oil pressure monitor among some other differences. The NAS aka NAFTA Sprinter OM612 and OM647 5 cylinder diesels never got the oil pressure monitor. We only have an oil level monitor.
vic
Unrelated.
The Dodge Crossfire has a version of the MB NAG1 transmission.
The Jeep OM612 diesel had an oil pressure monitor among some other differences. The NAS aka NAFTA Sprinter OM612 and OM647 5 cylinder diesels never got the oil pressure monitor. We only have an oil level monitor.
vicUnrelated.
The Dodge Crossfire has a version of the MB NAG1 transmission.
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AdrianD
Member
Re: OM612 low oil pressure when hot
It really was? I was under the impression that the Grand Cherokee was never offered with a diesel in the US until the WK generation, 2005+, which had the same drivetrain as the V6 NCV3 Sprinter.
Also as far as I know only, the only OM612 application with an oil pressure sensor is on the Jeep.
I can't wait to open up my old oil pump, as I found two pieces of a circlip in the oil cooler input, they got munched by the oil pump and probably caused some damage.
It really was? I was under the impression that the Grand Cherokee was never offered with a diesel in the US until the WK generation, 2005+, which had the same drivetrain as the V6 NCV3 Sprinter.
Also as far as I know only, the only OM612 application with an oil pressure sensor is on the Jeep.
I can't wait to open up my old oil pump, as I found two pieces of a circlip in the oil cooler input, they got munched by the oil pump and probably caused some damage.
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Re: OM612 low oil pressure when hot
2002–2005 2.7 L CRD Diesel Mercedes Benz Diesel 163 hp (122 kW) 295 lb·ft (400 N·m) Not Available in North America
https://en.wikipedia.org/wiki/Jeep_Grand_Cherokee#Engines_2
The fact that the Jeep OM612 engines have an oil pressure tap/monitor has been mentioned here on the forum. I ass-u-me'd that the reference was to Jeeps which were in N. America. I was wrong.
Thanks for the correction. Sorry for any confusion.
vic
You are correct. I stand corrected.
2002–2005 2.7 L CRD Diesel Mercedes Benz Diesel 163 hp (122 kW) 295 lb·ft (400 N·m) Not Available in North America
https://en.wikipedia.org/wiki/Jeep_Grand_Cherokee#Engines_2
The fact that the Jeep OM612 engines have an oil pressure tap/monitor has been mentioned here on the forum. I ass-u-me'd that the reference was to Jeeps which were in N. America. I was wrong.
Thanks for the correction. Sorry for any confusion.
vic
AdrianD
Member
Re: OM612 low oil pressure when hot
The time has come to change the oil again, so I took off the oil pan and replaced the oil pump in the process. Pretty simple procedure. Now for some carnage pics of the old pump:
This is what I found in the summer, at the oil cooler input. These two pieces went through the pump
First end plate (counting from pump input) has some nasty marks:
Pump gears look solid but check out the damage on this:
And the housing of the damaged gear:
Other gears, housings and end plates looked ok. With that kind of damage, no wonder I would have low oil pressure if it would heat up any amount over normal temperature.
Now for testing.
The time has come to change the oil again, so I took off the oil pan and replaced the oil pump in the process. Pretty simple procedure. Now for some carnage pics of the old pump:
This is what I found in the summer, at the oil cooler input. These two pieces went through the pump
First end plate (counting from pump input) has some nasty marks:
Pump gears look solid but check out the damage on this:
And the housing of the damaged gear:
Other gears, housings and end plates looked ok. With that kind of damage, no wonder I would have low oil pressure if it would heat up any amount over normal temperature.
Now for testing.
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AdrianD
Member
Re: OM612 low oil pressure when hot
Now, I've been driving like this for the past 42k miles, and who knows since when it had that damage. So hopefully the bearings are ok. During my ownership I haven't seen a degradation of the oil pressure, I assume that if the bearings would've taken damage from lack of lubrication, it should've gotten worse in such a long driving time.
If anything, once I replaced the oil cooler and cleaned the debris in the oil pump strainer, the oil pressure showed some improvement.
Now, I've been driving like this for the past 42k miles, and who knows since when it had that damage. So hopefully the bearings are ok. During my ownership I haven't seen a degradation of the oil pressure, I assume that if the bearings would've taken damage from lack of lubrication, it should've gotten worse in such a long driving time.
If anything, once I replaced the oil cooler and cleaned the debris in the oil pump strainer, the oil pressure showed some improvement.
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AdrianD
Member
Re: OM612 low oil pressure when hot
I know
Sadly I don't have a socket for the main cap bolts and I'm also a bit scared to undo rod or main bolts.
Around town the idle oil pressure stabilizes higher than it used to be and at 1500 rpm it's up to where it was in the past cruising at 2000 rpm.
Updates to come as I drive it some more
Later edit: Sorry about the pic size and thanks for the resize Vic. I need to change my imgur settings.
I know
Sadly I don't have a socket for the main cap bolts and I'm also a bit scared to undo rod or main bolts.
Around town the idle oil pressure stabilizes higher than it used to be and at 1500 rpm it's up to where it was in the past cruising at 2000 rpm.
Updates to come as I drive it some more
Later edit: Sorry about the pic size and thanks for the resize Vic. I need to change my imgur settings.
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AdrianD
Member
Re: OM612 low oil pressure when hot
Since everybody likes carnage pics, this is what happened to a hydraulic pump on a Case backhoe we used to own. The operator ran it low on oil. $1200 mistake, I was lucky to find an NOS pump in the US on the same day we took it apart. Dealer prices were 3 times that.
Since everybody likes carnage pics, this is what happened to a hydraulic pump on a Case backhoe we used to own. The operator ran it low on oil. $1200 mistake, I was lucky to find an NOS pump in the US on the same day we took it apart. Dealer prices were 3 times that.
AdrianD
Member
Re: OM612 low oil pressure when hot
I did some serious testing this weekend, I had to climb a steep slope off-road, with 4 people in the car, on slushy snow. Coolant got to 215 for a very short period of time and coincidentally I had to stop then, the oil pressure did not drop below the lowest mark on the gauge. Victory! Previously it would drop at zero on the gauge even before the coolant got that hot.
I did some serious testing this weekend, I had to climb a steep slope off-road, with 4 people in the car, on slushy snow. Coolant got to 215 for a very short period of time and coincidentally I had to stop then, the oil pressure did not drop below the lowest mark on the gauge. Victory! Previously it would drop at zero on the gauge even before the coolant got that hot.
Re: OM612 low oil pressure when hot
Salut Adi , deci ce pompa ai folosit pana la urma ?
6121810201 - the 613 longer pump , s-a potrivit plug&play ?
EDITED/ TRANSLATED)))
Hi Adi , so what pump did you end up using ?
6121810201 - the 613 longer pump , was is a straight fit - plug&play ? - hi5 Aqua !
Salut Adi , deci ce pompa ai folosit pana la urma ?
6121810201 - the 613 longer pump , s-a potrivit plug&play ?
EDITED/ TRANSLATED
)))Hi Adi , so what pump did you end up using ?
6121810201 - the 613 longer pump , was is a straight fit - plug&play ? - hi5 Aqua !
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Re: OM612 low oil pressure when hot
Hi Adi, so the pump you use anyway?
vic
For others not familiar, Google says Romanian.
Hi Adi, so the pump you use anyway?
vic
AdrianD
Member
Re: OM612 low oil pressure when hot
OM612 pump off a CLK270. OM613 pump would've required shortening the suction tube.
There's an AMG C30 CDI pump for sale in Germany, that one should fit without any changes and it's as big as the OM613 pump.
Actually Lemioux12 is in my friends list on facebook .
More on the subject: the original sender failed, I replaced it with a Standard Motor Products one, it showed zero at idle and then it started puking oil. Then I purchased a Blueprint one and the oil pressure on the dash is rock solid.
I cut the last oil filter and found 4 or 5 shiny specs, very very small. According to the interwebs it should be fine. I'm still bummed that I did not take off a bearing cap when the oil pan was off.
OM612 pump off a CLK270. OM613 pump would've required shortening the suction tube.
There's an AMG C30 CDI pump for sale in Germany, that one should fit without any changes and it's as big as the OM613 pump.
Actually Lemioux12 is in my friends list on facebook .
More on the subject: the original sender failed, I replaced it with a Standard Motor Products one, it showed zero at idle and then it started puking oil. Then I purchased a Blueprint one and the oil pressure on the dash is rock solid.
I cut the last oil filter and found 4 or 5 shiny specs, very very small. According to the interwebs it should be fine. I'm still bummed that I did not take off a bearing cap when the oil pan was off.
Re: OM612 low oil pressure when hot
Thanks for the follow-up.
I wouldn't beat yourself up about that... I mean, You shouldn't worry about it. The oil pressure is good. After the service and miles you have since driven the bearings must be ok. It is unlikely that a visual inspection would have revealed much. If the damage back then was bad enough to see, by now bad bearings would have reared their ugly heads.
vic
Thanks for the follow-up.
I wouldn't beat yourself up about that... I mean, You shouldn't worry about it. The oil pressure is good. After the service and miles you have since driven the bearings must be ok. It is unlikely that a visual inspection would have revealed much. If the damage back then was bad enough to see, by now bad bearings would have reared their ugly heads.
vicMidwestdrifter
Engineer In Residence
Re: OM612 low oil pressure when hot
The bearing material/structure is very resilient. If it was bad enough to hit the cascade failure point, you would know by now. Likely a visual inspection would show minimal damage, only a plastigauge check for clearances would have given useful information.
The bearing material/structure is very resilient. If it was bad enough to hit the cascade failure point, you would know by now. Likely a visual inspection would show minimal damage, only a plastigauge check for clearances would have given useful information.
Hi Everyone,
It's my first post, nevertheless I also suffer with low oil pressures during idle loads, on hotter days the pressure gauge falls to 0, then I have to rev it slightly (up to 1000rpm) to get the pressure up. My engine temperature usually sits at 100C (212F). I own the Jeep WJ with OM647 engine, I drive it hard at times, on my last safary in the sand dunes, the engine temp rose up to 110C (230F) and the oil pressure was falling constantly to 0 during idle. So I had to let it cool down a bit.
I think the reason of my higher temperatures might be a blocked radiator, as whilst driving on the highway the temp sits just below 100C (212F), but not at 90C (194F as it should), the thermostats are rated at 87C (188.6F) on the Jeep WJ OM647. I also have a suspension lift and larger tyres (32") so it's much more load on the engine compared to a stock vehicle.
Based on this topic and other information on the web I assume the oil pump is to blame. My car has approx 280kkm on the clock, it looks like most of the OM612/647 engines have oil suffocation in this running range.
I have ordered a new pump. Part Mercedes part number 612 181 02 01.
But once it arrived, I see that it's the longer (more powerful?) pump. There are two pumps available with this part number, one two chamber (OEM) and the longer one I received.
OEM pump fitted on the Jeep WJ with OM647 engine:
My new pump is one section longer, although with the same part number:
It also has an additional hole in the shiny section, any thoughts what is it used for? Searching photos it looks like nothing connects to it.
Comparing both pumps based on the photos (I still havent removed my old pump) , it looks like I can still fit the longer one, although it will require some modification of the tubes.
AdrianD, would you remember will the larger pump fit?
One of the tubes will have to be cut and extended, as otherwise it will not pass the corner of the longer pump.
The other tube will need to be cut and shortened. Is there enough room for the pump itself to fit?
Otherwise I will have to disassemble both pumps and build one from two.
It's my first post, nevertheless I also suffer with low oil pressures during idle loads, on hotter days the pressure gauge falls to 0, then I have to rev it slightly (up to 1000rpm) to get the pressure up. My engine temperature usually sits at 100C (212F). I own the Jeep WJ with OM647 engine, I drive it hard at times, on my last safary in the sand dunes, the engine temp rose up to 110C (230F) and the oil pressure was falling constantly to 0 during idle. So I had to let it cool down a bit.
I think the reason of my higher temperatures might be a blocked radiator, as whilst driving on the highway the temp sits just below 100C (212F), but not at 90C (194F as it should), the thermostats are rated at 87C (188.6F) on the Jeep WJ OM647. I also have a suspension lift and larger tyres (32") so it's much more load on the engine compared to a stock vehicle.
Based on this topic and other information on the web I assume the oil pump is to blame. My car has approx 280kkm on the clock, it looks like most of the OM612/647 engines have oil suffocation in this running range.
I have ordered a new pump. Part Mercedes part number 612 181 02 01.
But once it arrived, I see that it's the longer (more powerful?) pump. There are two pumps available with this part number, one two chamber (OEM) and the longer one I received.
OEM pump fitted on the Jeep WJ with OM647 engine:
My new pump is one section longer, although with the same part number:
It also has an additional hole in the shiny section, any thoughts what is it used for? Searching photos it looks like nothing connects to it.
Comparing both pumps based on the photos (I still havent removed my old pump) , it looks like I can still fit the longer one, although it will require some modification of the tubes.
AdrianD, would you remember will the larger pump fit?
One of the tubes will have to be cut and extended, as otherwise it will not pass the corner of the longer pump.
The other tube will need to be cut and shortened. Is there enough room for the pump itself to fit?
Otherwise I will have to disassemble both pumps and build one from two.
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