[mangos86q]

I keep reading horror stories about n55 engines seizing with failed rod bearings after OFHG changes. Has anyone experienced this? Mine isn't leaking currently, but I know its only a matter of time.

[95blkmax]

LMAO! Man stop reading car stories from those flat-earth websites jk

What WILL kill rod bearings and seize engines is running them out of oil (like if you have a leak and don't take care of it). Or, if you did the OFHG and you didn't properly torque down the bolts... you'll end up with a leak... which if you don't notice in time can cause you your engine.

So in short, no. Changing gaskets doesn't lead to seized engines or killing rod bearings. What DOES cause them is having leaky gaskets and not monitoring your oil level allowing it to starve. Hope that answers your question!

[doodlebro]

Originally Posted by 95blkmax

LMAO! Man stop reading car stories from those flat-earth websites jk

What WILL kill rod bearings and seize engines is running them out of oil (like if you have a leak and don't take care of it). Or, if you did the OFHG and you didn't properly torque down the bolts... you'll end up with a leak... which if you don't notice in time can cause you your engine.

So in short, no. Changing gaskets doesn't lead to seized engines or killing rod bearings. What DOES cause them is having leaky gaskets and not monitoring your oil level allowing it to starve. Hope that answers your question!

Have you been living under a rock or something? This is a well known issue and your entire comment doesn't acknowledge this. Very unhelpful

The issue with N55 OFHG and siezing engines is apparently related to the external oil cooler. The basic heat exchanger shouldn't have this problem since it is all attached to the oil filter housing and doesn't pipe down/back up from a radiator in the bumper...

Anyways, the problem comes down to the oil pump not being able to clear air bubbles in the oil cooler, resulting in starvation. Procedure from BMW is to prime the oil system for 30 seconds (with ignition or fueling disconnected) before starting. BUT!

Even with that procedure followed to a tee, people have lost engines to this. I have heard it is related to the idle oil pump speed and that immediately getting in and driving will bring revs up enough to deal with the air pocket in the oil cooler before serious damage occurs. Most of the time this issue immediately shows up (within 300 miles). I haven't seen many N55's with this issue once they get higher than that. I have also heard that people are waiting too long to do the job, leading to dirt/gunk dropping down oil galleys. This is less common and obviously an install issue, but it has happened.

N55: https://www.1addicts.com/forums/show....php?t=1537202

N55: https://www.reddit.com/r/Justrolledi...ilter_housing/

N55: https://bmw.*********** .com/threads/broken-n55-crankshaft.4716/ < sp00lstreet but we still have censorship

N54: https://www.n54tech.com/forums/showt...t=57495&page=2

This is very common people.

[95blkmax]

WOOOOOW I guess I have been dude I've never heard of this! But thank you for sharing and explaining it in detail for us under-rock residents lolol!

[ziekxq]

I second that information... My BMW mechanic told me this is true story and they had this happen to cars with as low as 30k miles. I have external oil cooler and my OFHG was replaced 50k miles ago. So whoever did the job did it good.

[BimmerHausPerformance]

WOW i just did my OFHG but everything is fine... Is it only when you do the pan too? How is the oil bubble introduced to the pump? Wouldn't a normal oil change do this too?

[doodlebro]

Originally Posted by BrowBMW

WOW i just did my OFHG but everything is fine... Is it only when you do the pan too? How is the oil bubble introduced to the pump? Wouldn't a normal oil change do this too?

The bubble is not in the pump, is in the oil cooler which breaks off of the OFHG on the cars that have it.

[ziekxq]

Originally Posted by BrowBMW

WOW i just did my OFHG but everything is fine... Is it only when you do the pan too? How is the oil bubble introduced to the pump? Wouldn't a normal oil change do this too?

Yes... My mechanic said it has happen on oil changes too.

[Surly73]

Originally Posted by doodlebro

.

Anyways, the problem comes down to the oil pump not being able to clear air bubbles in the oil cooler, resulting in starvation. Procedure from BMW is to prime the oil system for 30 seconds (with ignition or fueling disconnected) before starting. BUT!

Even with that procedure followed to a tee, people have lost engines to this. I have heard it is related to the idle oil pump speed and that immediately getting in and driving will bring revs up enough to deal with the air pocket in the oil cooler before serious damage occurs.

I remember posting a PSA about this about a month ago - not sure anyone believed me

My problem with the recommendation is this: If the problem is insufficient oil pump speed and pressure during idle - why is the speed and pressure SUFFICIENT at starter speed? That just doesn't make sense. If the issue was loss of prime - sure. If the issue is oil cooler air bubble, cranking on the starter isn't going to help.

The N55 has an electronically controlled variable-displacement oil pump. I've seen no indication in my documentation that extra volume/pressure is called for during start that is not called for during idle.

Because of the high amount of electronic control, I would expect a specific ISTA+ oil priming procedure. Time to do some more research.

I'd also love some iron clad information that if you don't have the external oil/air cooler you aren't at risk (since I don't have one )

[BimmerHausPerformance]

So do I need to be nervous each time I change my oil? Think of how many N55's with oil coolers are out there and get their oil changed constantly... this has to be some sort of weird anomaly.

[Unspec]

Originally Posted by BrowBMW

So do I need to be nervous each time I change my oil? Think of how many N55's with oil coolers are out there and get their oil changed constantly... this has to be some sort of weird anomaly.

I don't think oil changes touch the oil in the cooler. After all, you'd have to undo the hoses to drain that oil since it sits at the filter area, way higher up than the cooler. So in theory it shouldn't cause an issue.

[BimmerHausPerformance]

Anyone have a pic/image of where the pump is that get's the air bubble?

[lsturbointeg]

we just did mine yesterday since we changed the oil filter housing gasket and oil cooler gasket. Burrninja and i performed this by priming the oil system for 30 seconds (with ignition or fueling disconnected) before starting. there's 3 fuses we had to pull in the trunk. from there he than had the coolant capped removed to where you can see it spitting into the reservoir where he would keep adding blue coolant until it stopped.

[ramman434]

Picture of the fuses to pull? For future reference for all of us when priming the system.

[lsturbointeg]

Originally Posted by ramman434

Picture of the fuses to pull? For future reference for all of us when priming the system.

i'll take some pictures when i get off work today. there's a diagram that's stored next to your fuses but it's the fuel logo i believe and it has 3 fuses #'s next to it. 134(5), 135(5) and 189(20)? i'll confirm this like i said when i get home. this prevents the car from starting so it allows the priming of the oil system

[Unspec]

Originally Posted by BrowBMW

Anyone have a pic/image of where the pump is that get's the air bubble?

Pretty sure there's no dedicated pump for the oil cooler. It's the same oil pump that is used for the rest of the oil system.

[ziekxq]

Originally Posted by Unspec

I don't think oil changes touch the oil in the cooler. After all, you'd have to undo the hoses to drain that oil since it sits at the filter area, way higher up than the cooler. So in theory it shouldn't cause an issue.

The mechanic that works on my car said he seen and experienced n55 engine seizing after oil changes.

[Unspec]

Originally Posted by ziekxq

The mechanic that works on my car said he seen and experienced n55 engine seizing after oil changes.

You sure he's specifically talking about the ones with the oil cooler?

[Bmwdoubles_]

I think there's a YouTube or maybe FCP video that shows refilling through the OFHG

[ziekxq]

Originally Posted by Unspec

You sure he's specifically talking about the ones with the oil cooler?

No he never mentioned oil cooler. He just said they had few n55 that came in for oil change and they end up seizing the engine after oil change. He did say it was caused due to air bubbles in the pump/line I don't remember that part.

[lsturbointeg]

Originally Posted by Bmwdoubles_

I think there's a YouTube or maybe FCP video that shows refilling through the OFHG

that's what we did. we filled the oil in the OFHG, added some oil to the inside of the filtration than added the rest in the normal oil refill cap

[lsturbointeg]

Originally Posted by Bmwdoubles_

I think there's a YouTube or maybe FCP video that shows refilling through the OFHG

is this the same Bmwdoubles?? your post count is off