1976 BMW 530i "Eleanor" rebuild project

Post your E12 technical questions and comments here. Please, no off-topic posts.

Moderators: Mike W., Pierre

User avatar
keehn
Posts: 199
Joined: Tue Oct 01, 2019 5:14 pm
Location: Clear Spring, MD

Re: 1976 BMW 530i "Eleanor" rebuild project

Post by keehn »

Moving onto measuring gudgeon pins.

Image

I moved to a more thorough blueprinting spec sheet to capture various measurements.

Image

I also took the opportunity to remove the old piston rings from each piston. There are three rings in total per piston.

Image

One of the rings broke when I removed it. I didn't use any tools to remove the rings, only my hands. While these rings are strong, they are VERY brittle!

Image

A close examination of the oil scraper ring shows the importance of regular oil changes. Because this engine has only seen conventional oil thus far, the scraper rings have sludge build up inside them. This is a sign of irregular oil changes.

Image

I moved back to measuring the Gudgeon pins. Here, I'm measuring the diameter.

Image

And the length. Each pin was within spec.

Image

I also measured each piston per recommended measure points. Each piston measured out within spec as well, surprisingly.

Image

It's also important not to forget the Gudgeon pin bushing. This bushing is press-fitted into the upper connecting rod and provides a wear surface for the Gudgeon pin to roll on.

Image

I don't know of any other effective means of removing these bushings, so I rely on a small metal saw to remove them.

Image

It is VERY important to stop frequently and ensure that the conrod itself isn't being cut into. Here, the bushing is almost cut entirely.

Image

And success! the bushing is free from the conrod.

Image

Next, because it was a nice day, I took advantage and wheeled the block outside for degreasing and pressure washing.

Image

Because the block is over 200k miles, I also decided to remove the freeze plugs. To remove, simply take a chisel or other flat object that can withstand a 5 lbs hammer, and hammer the side of the plug until it gives way. I noticed with this block that the plugs did not swivel inside their holes, instead, the entire plug pushed in, requiring me to fish each plug out with channel locks. In order to remove, I had to tap the channel lock handle downwards to provide the force needed to deform the plug enough to be removed. The top of the channel lock against the engine block served as a fulcrum point.

Image

And just like that, the plug is removed.

Image

And I thought the coolant passages looked TOO clean...here, I uncover evidence of serious buildup.

Image

And, just like the plug, buildup can be observed on the coolant passage walls by each cylinder. I made sure to focus some of my pressure washing directly inside these channels.

Image

I found it simpler and less time-consuming to just knock each plug inwards at once, and then use the channel locks to remove them.

Image

Here's a closer look at the scale buildup on one of the plugs.

Image

Once again, the pressure washer is employed.

Image

And the block is now pressure washed. I did soak it in Zep degreaser but forgot to take a pic.

Image

Of course, the problem of exposing any sort of untreated steel to water is flash rust. Not a problem though, as the next step is to electrolytically remove all rust from this block.

Image

Regardless though, the block IS cleaner, despite the inability of the pressure washer to completely remove the smeg.

Image

There is more smeg on this side...that's some caked on dirt!

Image

Now, the part the block has been waiting for! I have a container large enough to hold the block, six 2' steel rods, and some washing soda.

**CAUTION** (if you choose to replicate this) Be sure to NOT, I repeat, NOT use STAINLESS steel for cathode rods! Using stainless steel with this process will produce hexavalent chromium - a DEADLY toxin. Remember the movie "Erin Brockovich"? The chemical that was poisoning her clients was hexavalent chromium!!

Again, NO STAINLESS STEEL!!!!

Also, make sure to use WASHING soda, not BAKING soda. The washing soda is important, as it serves as an electrolyte for the current to better pass through the water.

Image

As I was going to place the block level down into the container, I wanted to use the oil pan bolts to ensure the block stands off the bottom a little bit. Here I'm leveling out each bolt to ensure each one is equally supporting the block.

Image

The block is now off the stand, ready for its rust removal bath!

Image

Filling up the container. Note that the cloudy water is merely the washing soda mixed up in solution.

Image

I chose to use a head bolt to serve as the anode connector.

Image

Here, I've placed the cathodes at strategic points in the container.

Electrolytic rust removal requires that the cathode and anode be within direct "sight" of each other. If either is blocked, or otherwise out of "viewing" angle, then the rust removal cannot occur. That's why I have six cathode rods in total; So each can "view" all sides of the block at once, ensuring a thorough rust removal process occurs.

Image

Here, I've used 12 AWG wire to connect the six cathode rods together as one. Note that I bridged the two middle rods, this is to ensure a somewhat equal voltage flow occurs within the circuit.

The block itself is NEGATIVE. The steel rods are POSITIVE. Reverse these polarities and rust removal will not occur.

Image

Just a couple minutes in, I saw the first significant bubbling occur. The grease is being pushed away by the hydrogen and oxygen gas that's forming. This is also confirmation that the washing soda is sufficiently ratio'd as the electrolyte.

More to come.

Mike
canada karl
Posts: 1058
Joined: Tue Jan 06, 2009 3:50 pm

Re: 1976 BMW 530i "Eleanor" rebuild project

Post by canada karl »

Great series of pics. The restoration is coming along nicely. :D
1976 530i. BMW 59 Triumph TR3A(rolling resto). 67 Triumph TR4A(salvageable). 86 900S Winter car
User avatar
10ringarcher
Posts: 100
Joined: Sun Dec 27, 2015 12:26 am
Location: NY

Re: 1976 BMW 530i "Eleanor" rebuild project

Post by 10ringarcher »

What an excellent and thorough write up. Pictures help tremendously. Thank you for taking the time to share with the community.
User avatar
keehn
Posts: 199
Joined: Tue Oct 01, 2019 5:14 pm
Location: Clear Spring, MD

Re: 1976 BMW 530i "Eleanor" rebuild project

Post by keehn »

You are both welcome :)

I wanted to share the "morning-after" pics of the electrolytic rust removal effort...

Image

Taken just a few minutes before I posted this. Just a short ~14 hours after beginning, this is the effects of rust removal.

Image

Holy rust-mountains Batman! Now, the importance of smeg removal via pressure washing beforehand are apparent. Had I simply dunked the dirty block into the solution, I would have FAR more of a greasy mess to clean up, versus the grease here and there.

Anyways, I thought this was worth an immediate share. Hope everyone gets a kick out of it.

Mike
User avatar
528i-1981
Posts: 557
Joined: Wed Feb 07, 2018 5:50 am
Location: Franklin, TN

Re: 1976 BMW 530i "Eleanor" rebuild project

Post by 528i-1981 »

Wowzie. Mike, what did you use as a power supply (voltage/ amperage)?
(oo=00=oo) Eric
1981 528i Manual
User avatar
keehn
Posts: 199
Joined: Tue Oct 01, 2019 5:14 pm
Location: Clear Spring, MD

Re: 1976 BMW 530i "Eleanor" rebuild project

Post by keehn »

14.6 volts, 5.0 amps.

It's a Lithium Iron Phosphate battery charger from Amazon. Really, any 12v "dumb" charger will work fine (one that doesn't turn off by itself). Obviously, as rust accumulates on the cathodes, impedance will rise. It is important to remove each cathode rod and clean them to ensure current will continue to flow as well as possible.

How to know it's working? Just stand by for a few minutes and ensure the solution is bubbling all around the block (or object you are removing rust from).

Mike
User avatar
keehn
Posts: 199
Joined: Tue Oct 01, 2019 5:14 pm
Location: Clear Spring, MD

Re: 1976 BMW 530i "Eleanor" rebuild project

Post by keehn »

I decided to keep the block in solution for ~ 60 hours to ensure thorough rust removal. Today, I removed the block from the electrolytic rust removal solution.

Image

I hooked up the chains to two head bolts to raise the block.

Image

Block being raised out of solution. Pieces of...rust scum lifting with block.

Image

The block got rolled out to my driveway to begin the pressure washing process.

Image

A closer look at the block with rust scum.

Image

The block while getting pressure washed.

Image

The pressure washing has finished. The block is now attached to the engine stand.

Image

A look at the other side of the block.

Image

A picture of one of the coolant channels that run around the cylinder wall.

Image

Another one.

Image

And another.

Image

And another...you get the idea.

Image

The block doesn't look all that great, now that it's dried off. Flash rust has taken hold.

Image

Even with ~ 60 hours of cleaning, some smeg remains inside the crankshaft well.

Image

A close up of some flash rust. I didn't want to apply WD-40 because media blasting is my next step, and I need to keep the block dry to make blasting easier and more effective.

Image

Some more flash rusting. Again, looks like hot garbage right now, but the block will get better.

Image

Despite the flash rusting, it is easy to see remnants of the original block paint still intact. I need to remove ALL of this before I apply a new coat of paint.

Image

I opted to begin the media blasting immediately after taking the flash rust photos, so I rolled the engine stand back outside to prepare for the process.

Image

My portable media blaster. I use crushed walnut shells, as it doesn't pit metal surfaces. It takes longer to work with, but I'd rather have the peace of mind knowing that I'm not blasting a hole through my parts.

Image

Here's some results of walnut shell blasting. VERY nice!

Image

Here's a before-picture of the left-side block.

Image

And the after-picture.

Image

Here's a look of one cylinder coolant channel, now that it's dried. Looks pretty normal with no pitting.

Image

However, cylinder 6 does have pitting. I don't see anything alarming, but it does show that cylinder 6's piston was slapping, or behaving in a way that caused coolant vapor hammering, aka: pitting.

Most of my tools are purchased by need. Today, as I was media blasting the block outside on my driveway, I remembered how much I hated getting pelted by tiny walnut shells. As such, I am now seriously considering getting a media blasting cabinet from harbor freight to finish the job. The block is not the only part that I'm going to media blast, so it may be likely that my next series of photos will include a new media blasting cabinet.

That's it for now.

Mike
canada karl
Posts: 1058
Joined: Tue Jan 06, 2009 3:50 pm

Re: 1976 BMW 530i "Eleanor" rebuild project

Post by canada karl »

Wow those walnut shells do a nice job on the clean up. :D
1976 530i. BMW 59 Triumph TR3A(rolling resto). 67 Triumph TR4A(salvageable). 86 900S Winter car
User avatar
keehn
Posts: 199
Joined: Tue Oct 01, 2019 5:14 pm
Location: Clear Spring, MD

Re: 1976 BMW 530i "Eleanor" rebuild project

Post by keehn »

After a LONG delay with getting a blast cabinet, setting it up (which was tedious), and having to fix the ridiculous blast gun (I had to chamfer down the air blast nozzle inside the gun to create enough suction), I decided to blast the hardest part first: The engine block.

Image

I'll start with some pics of the block in the cabinet. Shoehorning this block into the cabinet takes a bit of finesse.

Image

Here's a picture of the block before I started blasting.

Image

Another photo of the block in the cabinet. The cabinet's built-in light is inadequate (although it was upgraded to LED lights from fluorescent in previous models), so I used a 1200 lumen portable LED light I laid on the viewing glass, and this worked...okay.

Image

From my perspective, the block looks pretty darn clean.

Image

So, in order to lug this ~135lbs cast iron engine block in and out of the blast cabinet, I used the engine hoist sort of like a front-loader. I placed straps around the block and the hoist arm to move the block in and out within the narrow doorway.

Image

Here's a better picture of how I strapped the block to the engine stand. Yes, I was nervous and yes, I did keep my body out of the way as I moved the block around.

Image

So...it appears that I did NOT remove all of the old paint. As my viewing angle in the cabinet is limited, I thought I removed everything...

Image

A closer look at the missed block paint. I took a brass wheel and removed what I could.

Image

This side, I was more thorough with removing old paint.

Image

You can see all of the walnut blast media still occupying the block voids.

Image

I also remembered to clean the rear main seal surface before I put the block back on the stand.

Image

A dusty block crankshaft alley. All of this will take a LOT of brake cleaner and acetone to fully clean prior to paint.

Image

How the block looks after I went over it with a brass wheel. Needless to say, I have no intention of putting that hunk of steel back in the blast cabinet! I'll finish what I can with a wire wheel.

Image

Now that I have a blast cabinet, I'm moving onto cleaning small engine parts. I'm starting with the pistons and oil pump...

More to come

Mike
canada karl
Posts: 1058
Joined: Tue Jan 06, 2009 3:50 pm

Re: 1976 BMW 530i "Eleanor" rebuild project

Post by canada karl »

The walnut shell blasting made for an amazingly clean block. Now I'm curious as to what the piston tops are going to look like when cleaned up. I'm looking forward to the next installment. :)
1976 530i. BMW 59 Triumph TR3A(rolling resto). 67 Triumph TR4A(salvageable). 86 900S Winter car
User avatar
keehn
Posts: 199
Joined: Tue Oct 01, 2019 5:14 pm
Location: Clear Spring, MD

Re: 1976 BMW 530i "Eleanor" rebuild project

Post by keehn »

Thanks Carl. That will be my next upload.

For everyones awareness, you can view FULL RESOLUTION if you right-click on any image and select "Open image in new tab" (wording depends on browser you use).

I compress every photo I upload, but retain the full resolution. So if there's something you can't quite make out in an image, this option allows you to see it how the camera took it.

No comments on my dirty garage though! :lol:

Mike
User avatar
keehn
Posts: 199
Joined: Tue Oct 01, 2019 5:14 pm
Location: Clear Spring, MD

Re: 1976 BMW 530i "Eleanor" rebuild project

Post by keehn »

Now that the block has been blasted, I moved onto media blasting the pistons.

Image

All pistons are in the cabinet. I also took the opportunity to blast 1/2 of the oil pump.

Image

All was going well until I noticed that I couldn't get any walnut blast through the oil scraper holes.

Image

Upon closer examination, I noticed that all of the pistons had a few or more holes clogged with oil. The dust from the walnut media merely exposed the clogs.

Image

Not all holes were clogged however.

Image

This was a common sight on all six pistons. No doubt these clogs promoted the scratches on the piston skirts.

Image

It really is amazing how dust can reveal issues. Note how only two holes are clear. The other two are semi-obstructed. This is a view of the piston from underneath.

Image

Again, only two holes are visible on this piston interior.

Image

And this piston's oil holes are completely obstructed.

Image

Each piston has eight oil holes. A pick tool should be able to pass through unobstructed as shown here. In fact, that's how I cleared each hole. I used the media blaster to take care of what smeg the pick didn't remove.

Image

Now, each piston is cleaned, but dusty from the media blaster.

Image

The piston heads are clearly visible as well. You can read the letters AND see the arrow, which shows the orientation of the piston as it should be installed (arrow should point to front of engine block). Also, each piston showed detonation damage of varying severity. Because the damage is centered on the crown and I have no plans to race Eleanor, I see no reason why I cannot reuse these pistons.

Image

I mulled over getting the Harbor Freight parts cleaner, but instead purchased a cleaning pump and brush. Along with a five-gallon bucket and shallow rubbermaid container (with a 90 degree elbow and hose emptying into the bucket) I made this "portable" alternative. It was cheaper as well.

Image

A better look at the setup in its entirety. I used Zep industrial purple cleaner with only 1/2 gallon water to keep the fluid level over the pump as excess collected in the rubbermaid. Not all fluid returned to the bucket, as I installed the 90 degree elbow ~ 1/2" above the container's floor.

Image

After I media blasted the pistons, I placed them back in order for obvious reasons.

Image

After I parts washed the pistons, I noticed that they are not all forged aluminum. There are two strips of steel embedded parallel to each other inside the pistons. No worries, as a quick blast with a bronze wheel will remove any flash rust.

Image

Also notice how clean the oil scraper holes are now! I am certainly glad I took the effort to tear the engine down this far, as continued operation of the engine, as it was, would have no doubt, led to mechanical failure.

Image

After I parts-washed each part, I put them through the dishwasher to remove any residual cleaner. The white spots are simple oxidation that rub off easily.

Image

Here are some of the parts cleaned thus far. I took the time to clean both the interior and exterior of the bell housing. The black that's on the flywheel cover is the remaining paint.

Image

The parts cleaner is great for everything. I even washed the air cleaner and CAREFULLY washed the air flow sensor housing. The vane movement in the air flow sensor housing was smoother and easier after I washed it.

Image

The airbox waiting for the dishwasher.

Image

Now, this was a PITA! It took me nearly three hours to scrub :roll:

Image

I gave nearly as much attention to the oil pan interior as the exterior, mainly because I didn't want the new synthetic oil doing double-duty the first 8-12k miles; lubricating AND removing the conventional oil sludge. Removing the oil sludge before reassembly gives the obvious advantage of reducing chance of blockage, should a chunk of sludge break free.

Image

It was tough, but I was able to get a great deal of the oil sludge out from underneath the oil baffle. I took care to ensure all sides of the baffle (where oil drains) were cleaned.

Image

THIS took me the longest time! The decades of smeg took a brass brush, a nylon brush, and the power drill with small brass brush (to clean the nooks and crannies).

Image

This is the outer oil pump ring that rides on the inner oil pump. I was on the fence about replacing the inner and outer pump assemblies until I saw this; Noticeable grooves and pock marks.

Image

Even the interior of the pump ring shows visible wear from contaminants. Because I'll be running 5w30 synthetic oil, I want to make sure the pump will have the clearances necessary to provide proper oil flow.

That's it for now. I'm continuing to wash parts with the parts cleaner. I will soon be ready to hone the cylinders and prep the block for paint.

Mike
canada karl
Posts: 1058
Joined: Tue Jan 06, 2009 3:50 pm

Re: 1976 BMW 530i "Eleanor" rebuild project

Post by canada karl »

The pistons still look useable. Do the scratches have to be cleaned up with 1ooo grit sandpaper or left as is? Are the worn oil pump parts still available? Looks like they've ended on BMW Realoem?
Are there still E12's at wrecking yards in your city? There's none up here where I am.
The engine restoration is coming along nicely. :)
1976 530i. BMW 59 Triumph TR3A(rolling resto). 67 Triumph TR4A(salvageable). 86 900S Winter car
User avatar
keehn
Posts: 199
Joined: Tue Oct 01, 2019 5:14 pm
Location: Clear Spring, MD

Re: 1976 BMW 530i "Eleanor" rebuild project

Post by keehn »

Karl,

Yes, I also agree that the pistons are still usable. The pock marks can likely be sanded out, mainly to bring the crater edges down to prevent hot spots. I'm also going to spray the tops of the pistons with "cerakote". The cerakote will provide a ceramic barrier against heat absorption into the piston head. Google "cerakote piston coating" and you can see examples of other builders using this product. I'm also mulling with spraying this on the valve bottoms as well (also a common practice with high-performance builders).

As for the oil pump rotor and circular mechanism, they are both in my shopping cart that I'm amassing between Turner Motorsports, FCP Euro, and RockAuto. My wife agreed to "let" me use some of our upcoming tax return to purchase all necessary rebuild parts. J/K...my wife is really cool with this whole project, and she's excited to see "Eleanor" come back to life.

As for E12's in local wrecking yards? I honestly haven't bothered looking just yet. However, the beauty of our M30B30 blocks is they were used between multiple Bimmer models between the 70's into the mid-90's; Hence, spare parts are VERY abundant, to include oil pumps :wink: .

Mike
User avatar
keehn
Posts: 199
Joined: Tue Oct 01, 2019 5:14 pm
Location: Clear Spring, MD

Re: 1976 BMW 530i "Eleanor" rebuild project

Post by keehn »

Wanted to let everyone know that I finally got my tax return back and thus, was able to hit "checkout" on all my saved shopping carts.

The total amount?

....$2,971.15 :shock: :shock: :shock:

Mike
Post Reply