Engine replacement?

[fortunateson]

My '02 525 with 360,000 KMS is driving me nuts. The main problem is oil consumption. A litre every two weeks! Also, on decel when coasting down a steep grade and then reving up ebottom of the hill a puff of blue smoke. A puff when I have left the car overnight. If I leave the car for two or three hours a major 007 smoke screen. This sounds like valve seals to me. I ought about doing the work myself by renting the tool for the timing issue. However, I would think that the valve guides might be gone as well. That means taking the head off, parts, and machine work ($600-900). In addition my SAP works on the bench but not in the car. Replaced the fuse under the seat and no change.

So.... I have found an engine with approximately 75,000 miles on it for about $1,200 CDN plus install. E issues I have I think this is a smart move. Would you all think my appraisal of the "burning blue" and oil consumption sound accurate? Could it be a n issue with the CCV? I replaced the CCV last summer and the oil consumption did not improve.

Any ideas about the SAP issue?

Desperately seeking advice......

[edjack]

Might try a piston ring soak. The M54 is notorious for carboned up rings. Many on this forum have had success.

Have you checked the SAP relay? It's buried in the E-box, K6304.

[fortunateson]

I did do a piston soak which didn't do much at all. Would the seal-like symptoms also indicate a bad CCV? I will check the SAP relay but I will need a DIY to do so. Thanks.

[JimLev]

When you did the CCV did you replace all of the hoses and clean out the dipstick oil return section?
The relay is in the front part of the DME box next to the wiper relay(s). Search...CCN/CN has a posted a pic more than once.

[auaq]

Sounds like bad valve stem seals to me if you have replaced your ccv along with all other associated hoses.

[auaq]

Forgot to ask, but do you have any oil leaks? Did you check your oil filter housing gasket, oil pan gasket, valve cover gasket?

[effduration]

My vote is for the engine swap. You might be able to defray part of your costs by selling valve cover, vanos (reconditioned), and possibly even your head after a machinist goes thru it (if economic to do so).

I would also also suggest you considering doing the swap yourself. Remove exhaust and driveshaft. You can take engine and trans out together with a hoist and a balancer without removing the front clip - just pull the radiator. Unbolt the AC and power steering and strap to sides- keeping those systems closed. The electrical harness unplugs at DME box and comes out with engine. Replace the 2.5liter or add The 3.0 engine which also bolts in and could be a relatively easy power upgrade with a DME re flash

[fortunateson]

My vote is for the engine swap. You might be able to defray part of your costs by selling valve cover, vanos (reconditioned), and possibly even your head after a machinist goes thru it (if economic to do so).

I would also also suggest you considering doing the swap yourself. Remove exhaust and driveshaft. You can take engine and trans out together with a hoist and a balancer without removing the front clip - just pull the radiator. Unbolt the AC and power steering and strap to sides- keeping those systems closed. The electrical harness unplugs at DME box and comes out with engine. Replace the 2.5liter or add The 3.0 engine which also bolts in and could be a relatively easy power upgrade with a DME re flash

I wish this happened during thesummer when I had a lot of time on my hands. The tranny is a five speed manual: will the stick clear when pulling the engine and could that tranny be used with the 3.0 engine as those usually have a six speed. Are all m54 cranks usable with a standard? Do all cranks have the hole for a pilot bushing? Thanks for the input.

[effduration]

I installed an m52tu engine with GM auto trans bolted to it. You'll have to do some research but I seem to remember the manual trans is smaller than the Auto. Either way, I had inches of room to spare. I would bet the engine and manual trans would clear. I forgot to mention removing the hood. Mark the hood hinges on hood with a sharpie to make alignment on reattachment easier.

I don't think the 6-speed was offered in any 6 cyl 525i or 530i from '01 -'03

while the 525i and 530i sedan DO have different manual transmissions, the 3.0 engine should bolt right up to the 525i engine, though I have not done it.

[fortunateson]

Whenever I remove a hood or trunk lid I always drill two 1/8th inch hole on each hinge so I can line up when replacing with a couple of nails to e parts go back exactly where they were.

Does se anyone know for a fact that a 3.0 will bolt right up to the five speed from 2.5. Would there be any other concerns replacing the 2.5 with a 3.0?

[geargrinder]

will the stick clear when pulling the engine

This didn't get answered really - like most Euro trannies, the shifter doesn't stick directly straight up out of the transmission like some kind of 1947 Ferd or Chebby unit.

BMW shifters ride in a long carrier beam ("arm") kind of arrangement that attaches to the tranny on one side and plugs into a bushing on the body on the other. So that has to be disconnected when the tranny comes out anyway. You basically disconnect the actual linkage that goes back to the tranny ("selector rod"), and disconnect the arm from the tranny, (none of which is difficult operation), and then remove the tranny, and those 3 shifter parts (shift lever, linkage, carrier) are separated. Here's a shot of an e36 linkage but most BMW setups are pretty much same in principle even if the individual parts are different dimensions or shapes.

[mxchris727]

Just do the valve stem seals first. Why replace the engine if there may be a quicker fix? Do a leak down and compression test first if you want; but those 2.5L M54s have the thicker piston rings (than the 3L) and iron cylinder sleeves; I'm sure the bottom end is fine.

[djb2]

Whenever I remove a hood or trunk lid I always drill two 1/8th inch hole on each hinge so I can line up when replacing with a couple of nails to e parts go back exactly where they were.

Does se anyone know for a fact that a 3.0 will bolt right up to the five speed from 2.5. Would there be any other concerns replacing the 2.5 with a 3.0?

The e39 hood doesn't need to be removed. The hinges have factory holes to put the hood in a vertical 'service position'. One side is even threaded.

The M54B30 engine long block is externally the same as the M54B25. The difference is the crank/rods/pistons and cam grind. The 3.0 has a larger diameter intake system with a different MAF, but that only matters for replacement parts and programming the ECU.

The transmission fit is exactly the same. If swapping engines, it's pretty common to forget the pilot bearing and think that they are different.

Swapping transmission types is more involved. The drive shaft length is different, and the diff ratio might be an issue. Plus there are minor wiring harness differences, and ECU programming.

[fortunateson]

I was thinking about replacement due to the engine having 360,000 KMS, worried that the valve guides might need replacing as well as the valve seals, potential of having pistons all carboned up, and the potential of the internal SAP passages all carboned up. I was quoted $600-900 just to re and re the valve guides.

I thought that a replacement engine at around 120,000 KMS (75,000) would get me back to square one where I could do a piston soak once a year and try to keep up on maintaining a clean top end to prevent the problems I am currently having.

I'm still not convinced either way but leaning towards the replacement idea. I was quoted approximately $2200 all in for the engine and install.

[djb2]

It's not common for the M54 to need replacement valve guides, or valve seats. Which is good because the parts are expensive and difficult to replace.

I doubt that the valve stem seals commonly go bad, instead the failing rings mimic the symptoms commonly associated with leaking stem seals. But the stem seals are so easy and inexpensive that no one skips replacing them.

The pistons will have carbon on them. But cleaning isn't that big of a deal. It takes only a minute with the wire wheel to clean the bulk off of the crown, followed by a soak in ChemDip to clean the grooves. I spent much more time because I was concerned about mixing them up and wanted mine spotless, but I should have just tagged them when with a colored wire tie and let the cleaning solution do most of the work.

The M54 isn't know for clogging the secondary air ports. With the head off it's easy to verify that they are open and do a token cleaning.

[fortunateson]

Wow, you're talking about pulling the engine, taking off the head, pulling and cleaning pistons. Now that's a lot of work!

So do you think a longer piston soak would do the job? MMO? How could one test for bad valve seals? A leak down test usually would determine if the valves were not sealing I believe.

[djb2]

A leak-down test is a pretty good diagnostic. It will tell you if the valves aren't seating, or if the compression rings are badly leaking. It won't tell you if the oil control rings have failed.

There isn't a good test for bad valve stem seals, just observering the symptoms. They are possible to change without removing the head, but it requires re-timing the camshafts. It's much more work than doing a solvent soak of the combustion chambers just before each oil change, and the latter has a small chance of helping the problematic oil control rings.

[Jason5driver]

How old is the CCV and hoses.
I am not sure an engine swap is warranted.
I have used the A/C Delco cleaner and Seam Foam spray can, and sprayed the top of the pistons from the spark plug ports.
There is a noticeable difference after doing this.
I change the oil afterward.
Also, try to keep oil changes to no more than 5000 miles.
https://www.walmart.com/ip/ACDelco-F...&wl13=&veh=sem

http://www.autozone.com/fuel-and-eng...ner/461563_0_0

[fortunateson]

The CCV is just over a year old a son are the hoses. I would change the oil with Mobil 1 0/40 two or three times a year. The thing is that on decel, high vacuum, when I give some gas there I should a puff of blue as well when I leave it parked for an hour or two or three it looks like a industrial crop duster. I did a piston soak about a month ago and no difference. Everyone around here wants to take off the head to do valve stem seals which means $$$$.

Are oh thinking another soak and Seafoam application might fix this. 360,000 KMS on th clock. I would prefer not to do an engine swap if I can solve this problem. However, the stem seals job wouldn't cost nearly as much as an engine swap replacement engine having 120,000 KMS or 75000 miles.

[auaq]

Why do you have to take the head off to do the valve stem seals?? You only have to take the cams out, fill the cylinders with air pressure at TDC or stick some rubber hose (or something) in there to prevent the valves from dropping in, and then replace the seals.

[Jason5driver]

Use the CRC Valve cleaner.

[auaq]

Why do you have to take the head off to do the valve stem seals?? You only have to take the cams out, fill the cylinders with air pressure at TDC or stick some rubber hose (or something) in there to prevent the valves from dropping in, and then replace the seals.

I should actually say at the end of compression stroke for every cylinder when both valves are closed ...

[Jason5driver]

I should actually say at the end of compression stroke for every cylinder when both valves are closed ...

Have you done this? (Replace the valve stem seals)

[auaq]

Have you done this? (Replace the valve stem seals)

Nope. Never did one on my ex-530i or on any engine yet. However, the steps involved to R&R valve stem seals are no different for any engine.

[edjack]

The traditional method of replacing valve stem seals is to pressurize each cylinder to hold the valves closed before removing the tappets, keepers, and springs.

Some advocate jacking the right side of the car so the engine is vertical before introducing the solvent.