Re: 1976 BMW 530i "Eleanor" rebuild project
Posted: Sun Apr 12, 2020 9:14 pm
Moving onto the cylinder head.
I bought this AMC-manufactured head last year from the BMWCCA chapter I'm a member of. The head had been refurbished and had new valves lapped and ready to go. However, the head sat for several years uncovered, so a good deal of dirt had coated the interior. Additionally, the coolant channels have a coating of rust (in an aluminum head....), no doubt a result of the block it once lived on.
The first order of business was to remove the oil spray bar. On close inspection, I noticed that one of the holes was more of a dimple. I will be correcting this when I refurbish the spray bar.
A view of the exhaust side.
In order to remove the big nut from the camshaft, I used my cabled 3/4" Makita impact gun. This thing is a beast but HEAVY!
The nut can't back out due to a thin plate bent over, this keeps the nut in place, should it come loose.
At this point, I needed to figure out a non-destructive method of removing the camshaft. I researched the subject on google and found several forums mentioning an "Iron Maiden"-like device that forces all rocker arms downwards simultaneously. In doing so, this relieves the camshaft of any downward pressure, allowing it to be pulled out freely.
I had some angle and square steel lying around, so I welded together my own "Iron Maiden" device. Here it is installed.
I used a couple washers on each threaded rod to keep the device firmly pressed against the rocker arms. I'm not worried about warpage, as the pressure is evenly distributed between all four threaded rods. I checked the deck afterwards and there was no deformation found.
With the "Iron Maiden" fully pressed in, the camshaft easily slides out the front.
The camshaft, now fully removed from the cylinder head. I went ahead and removed the "Iron Maiden" at this point.
But before I removed the "Iron Maiden", I wanted to shoot exactly HOW the valves should be oriented when fully pressed.
The intake valve (small) must be pressed first, and the exhaust valve will tuck in right afterwards. Upon further research, the OEM tool apparently has different-length "fingers" to ensure that intake valves are pushed down before exhaust valves. My tool's fingers are even in length, but I was able to simulate different lengths by merely tightening the intake threaded rods down first, then the exhaust threaded rods next. It took me a couple times to get this right, it is possible to damage the valves, should they get pressed down together.
Here's a picture of my "Iron Maiden." Note the crappy welds and the unbrushed flux; I used gasless mig wire to put this together.
It may not be pretty, but it got the job done!
Now, I got the camshaft on my bench. I sanded the lobes and all oil surfaces with 500 grit sandpaper, but I didn't take any photos...
The rocker arm shaft end seals confused me at first, so I took out all but one, not knowing that they need to stay intact for removal.
Here's one of the shaft end seals. I wasn't thinking that it was what kept the hollow shaft sealed. I thought the shafts were sealed further in, and that the end seals needed to be removed to allow a slide-hammer removal (per the blue service manual), but I was not correct in that assumption. There is plenty of thread past each end seal to allow a threaded slide-hammer to grab the shafts.
One of the major preparations needing to be done is to remove the circlip that keeps each rocker arm in its place.
Pulling the rocker arm towards the spring reveals the circlip that keeps the rocker arm tensioned and in place.
The circlips are easy to remove, not removing anything more than a flat-headed screwdriver and a finger to keep the circlip in place while being tensioned off the shaft.
A closer look of the circlip.
As I removed the shafts, I placed the rocker arms in order for later cleaning.
How did I get the shafts out? A two-foot rod, a three foot rod, and a five-pound hammer. The shaft end seals MUST be installed for this to work properly. The rod needs to rest on the end seal and make sure it is threaded in as far as it can go; this gives the rod a firm non-slip surface to transfer the hammer's force.
Put the rod in here, give it whacks with the hammer. Don't be shy with the force, but don't go full-retard either. If you are hammering and nothing is moving, STOP, and inspect any potential obstructions. For me, there were no issues.
As the rod is hammered, the first rod will back out through the front.
Here's the first shaft removed. There are two half-shafts on each side.
Now, the cylinder head is torn down to nothing but valves and springs.
The biggest issue I ran into while pressing the valve springs down was holding the head down. I used my shop press, and with some towels, scrap bar steel, and light, but firm pressure, I was able to hold the head fast while I pressed each valve down to grab the valve keepers with my magnetic reach tool.
The valve spring tool I have was large enough for all but two valves. Here's the configuration I used to press each spring down.
All of the valves, springs, and keepers are now removed. All that's left are the valve seals. While they look new (and likely are), because this head had been sitting for quite a while, I opted to get new seals to install.
A view of the block, now laid bare.
Several of the valves had surface rust, including the valve seats on the head. I used the dremel to knock the rust off.
The next job I started was distributor rebuild. As I've been collecting and cleaning the various nuts and bolts throughout the engine, I used a cheap parts organizer from Harbor Freight to sort every nut and bolt by size and thread pitch. I kept the small nuts clamps belonging to the distributor in this organizer.
The distributor rebuild project has been on the back burner for a little while now, but since I am waiting on piston rings to arrive (standard size was too small for the cylinders, so I sent them back and ordered oversized rings) I figured I would tackle this diversion.
The first order of business was to replace the frayed ground wire I showed a while back (it was connected by a literal thread). I was dubious that my soldering iron would have the wattage to heat up the large metal plates, but I figured I would try anyways.
Also, I figured a piece of copper solder wicking wire would be a perfect replacement. The grounding wire looked virtually identical, so I went with this.
And yes, my soldering iron was insufficient to heat the metal plates, so I took them out to the garage for some extra heat, courtesy of a propane torch.
It's not all that clear, but I had to use my high-temp acid-core solder, as the low-temp solder simply burned off when heated by the torch. To avoid damage to the replacement ground wire, I had to heat up the piece by itself, and while the solder was still molten, I used my tweezers to insert the ground wire into the solder and held it in place until the solder hardened up.
This was probably the hardest part, maneuvering the ground wire to the second plate, but I eventually got it done.
Not my prettiest solder job, but a continuity check verified the integrity of the ground wire.
Here's the two special-order parts that Pelican Parts had to get shipped from Germany. I got a new dust shield and vacuum advance.
I made a few improvements: I reduced the tension on the ball (retained by the black "hungry-hungry hippo"-looking clip) so the upper plate slid with less resistance, I made sure to add more than enough ground wire, and I routed some of the Pertronix wire inside, so there will be less stress as the vacuum advance moves back and forth. I was able to move the upper plate freely when I sucked on the vacuum advance. While I can't know for sure, I can't help but feel that the old vacuum advance failure was hastened because it was so difficult to move the sliding plate, so when vacuum was applied, the diaphragm couldn't correctly distort.
After I rebuilt the distributor, I moved onto a second cleaning of the conrods.
Per the blue service manual, the conrod bolt must be replaced when servicing the bearings. As this is a 40+ year old engine, I felt it was cheap insurance, plus with the heavy steel conrods throwing that weight back and forth, these bolts have more than seen their fair share of stress. Removal was as simple as bracing each conrod in the vice and hammering out the bolt. To install, I'll use my shop press.
Each conrod and related parts degreased for a second time and ready for sleeve bearing and bolt installation.
How I organize each valve and related springs.
Here's a couple photos of the rocker arm half-shafts.
Intake and exhaust side-by-side. Note the differences between the oil passages - be sure to reinstall these correctly!
The rocker arms have been ultrasonically cleaned and everything is now organized and ready for dry-film application and then reinstallation.
While I had the ultrasonic heater working, I chose to try it on the dirty rear main seal cover...
...And it worked like a charm! The dirt wiped off easily.
I moved onto breaking down a fuel injector to see if I had to live with the pre-cut fuel lines.
All of the fuel injector fuel lines are showing cracks; I have no intentions of reinstalling these in this condition.
I carefully cut the fuel line away and found what I was hoping for - a barbed connection! This allows me to use my own hose clamp solution. I went ahead and got a bunch of "Oetiker" stepless ear clamps (newer BMW's use these as OEM); I will be using these to secure the fuel injector to the fuel rail.
I also proceeded to remove the large rubber ring which secures the injector to the manifold bracket. There is a circlip that holds it in place (kind of).
Here, you see that the circlip only keeps the rubber ring to one side of the large indent in the injector housing. I had to cut through the rubber ring to remove as well.
The small injector seal actually broke in two when I began to remove it, due to its brittleness.
The injector after a bath in the ultrasonic cleaner and a zip through the dremel to remove the surface rust. I'll take a clearer picture in my next set...
Until next time...MTF.
Mike
I bought this AMC-manufactured head last year from the BMWCCA chapter I'm a member of. The head had been refurbished and had new valves lapped and ready to go. However, the head sat for several years uncovered, so a good deal of dirt had coated the interior. Additionally, the coolant channels have a coating of rust (in an aluminum head....), no doubt a result of the block it once lived on.
The first order of business was to remove the oil spray bar. On close inspection, I noticed that one of the holes was more of a dimple. I will be correcting this when I refurbish the spray bar.
A view of the exhaust side.
In order to remove the big nut from the camshaft, I used my cabled 3/4" Makita impact gun. This thing is a beast but HEAVY!
The nut can't back out due to a thin plate bent over, this keeps the nut in place, should it come loose.
At this point, I needed to figure out a non-destructive method of removing the camshaft. I researched the subject on google and found several forums mentioning an "Iron Maiden"-like device that forces all rocker arms downwards simultaneously. In doing so, this relieves the camshaft of any downward pressure, allowing it to be pulled out freely.
I had some angle and square steel lying around, so I welded together my own "Iron Maiden" device. Here it is installed.
I used a couple washers on each threaded rod to keep the device firmly pressed against the rocker arms. I'm not worried about warpage, as the pressure is evenly distributed between all four threaded rods. I checked the deck afterwards and there was no deformation found.
With the "Iron Maiden" fully pressed in, the camshaft easily slides out the front.
The camshaft, now fully removed from the cylinder head. I went ahead and removed the "Iron Maiden" at this point.
But before I removed the "Iron Maiden", I wanted to shoot exactly HOW the valves should be oriented when fully pressed.
The intake valve (small) must be pressed first, and the exhaust valve will tuck in right afterwards. Upon further research, the OEM tool apparently has different-length "fingers" to ensure that intake valves are pushed down before exhaust valves. My tool's fingers are even in length, but I was able to simulate different lengths by merely tightening the intake threaded rods down first, then the exhaust threaded rods next. It took me a couple times to get this right, it is possible to damage the valves, should they get pressed down together.
Here's a picture of my "Iron Maiden." Note the crappy welds and the unbrushed flux; I used gasless mig wire to put this together.
It may not be pretty, but it got the job done!
Now, I got the camshaft on my bench. I sanded the lobes and all oil surfaces with 500 grit sandpaper, but I didn't take any photos...
The rocker arm shaft end seals confused me at first, so I took out all but one, not knowing that they need to stay intact for removal.
Here's one of the shaft end seals. I wasn't thinking that it was what kept the hollow shaft sealed. I thought the shafts were sealed further in, and that the end seals needed to be removed to allow a slide-hammer removal (per the blue service manual), but I was not correct in that assumption. There is plenty of thread past each end seal to allow a threaded slide-hammer to grab the shafts.
One of the major preparations needing to be done is to remove the circlip that keeps each rocker arm in its place.
Pulling the rocker arm towards the spring reveals the circlip that keeps the rocker arm tensioned and in place.
The circlips are easy to remove, not removing anything more than a flat-headed screwdriver and a finger to keep the circlip in place while being tensioned off the shaft.
A closer look of the circlip.
As I removed the shafts, I placed the rocker arms in order for later cleaning.
How did I get the shafts out? A two-foot rod, a three foot rod, and a five-pound hammer. The shaft end seals MUST be installed for this to work properly. The rod needs to rest on the end seal and make sure it is threaded in as far as it can go; this gives the rod a firm non-slip surface to transfer the hammer's force.
Put the rod in here, give it whacks with the hammer. Don't be shy with the force, but don't go full-retard either. If you are hammering and nothing is moving, STOP, and inspect any potential obstructions. For me, there were no issues.
As the rod is hammered, the first rod will back out through the front.
Here's the first shaft removed. There are two half-shafts on each side.
Now, the cylinder head is torn down to nothing but valves and springs.
The biggest issue I ran into while pressing the valve springs down was holding the head down. I used my shop press, and with some towels, scrap bar steel, and light, but firm pressure, I was able to hold the head fast while I pressed each valve down to grab the valve keepers with my magnetic reach tool.
The valve spring tool I have was large enough for all but two valves. Here's the configuration I used to press each spring down.
All of the valves, springs, and keepers are now removed. All that's left are the valve seals. While they look new (and likely are), because this head had been sitting for quite a while, I opted to get new seals to install.
A view of the block, now laid bare.
Several of the valves had surface rust, including the valve seats on the head. I used the dremel to knock the rust off.
The next job I started was distributor rebuild. As I've been collecting and cleaning the various nuts and bolts throughout the engine, I used a cheap parts organizer from Harbor Freight to sort every nut and bolt by size and thread pitch. I kept the small nuts clamps belonging to the distributor in this organizer.
The distributor rebuild project has been on the back burner for a little while now, but since I am waiting on piston rings to arrive (standard size was too small for the cylinders, so I sent them back and ordered oversized rings) I figured I would tackle this diversion.
The first order of business was to replace the frayed ground wire I showed a while back (it was connected by a literal thread). I was dubious that my soldering iron would have the wattage to heat up the large metal plates, but I figured I would try anyways.
Also, I figured a piece of copper solder wicking wire would be a perfect replacement. The grounding wire looked virtually identical, so I went with this.
And yes, my soldering iron was insufficient to heat the metal plates, so I took them out to the garage for some extra heat, courtesy of a propane torch.
It's not all that clear, but I had to use my high-temp acid-core solder, as the low-temp solder simply burned off when heated by the torch. To avoid damage to the replacement ground wire, I had to heat up the piece by itself, and while the solder was still molten, I used my tweezers to insert the ground wire into the solder and held it in place until the solder hardened up.
This was probably the hardest part, maneuvering the ground wire to the second plate, but I eventually got it done.
Not my prettiest solder job, but a continuity check verified the integrity of the ground wire.
Here's the two special-order parts that Pelican Parts had to get shipped from Germany. I got a new dust shield and vacuum advance.
I made a few improvements: I reduced the tension on the ball (retained by the black "hungry-hungry hippo"-looking clip) so the upper plate slid with less resistance, I made sure to add more than enough ground wire, and I routed some of the Pertronix wire inside, so there will be less stress as the vacuum advance moves back and forth. I was able to move the upper plate freely when I sucked on the vacuum advance. While I can't know for sure, I can't help but feel that the old vacuum advance failure was hastened because it was so difficult to move the sliding plate, so when vacuum was applied, the diaphragm couldn't correctly distort.
After I rebuilt the distributor, I moved onto a second cleaning of the conrods.
Per the blue service manual, the conrod bolt must be replaced when servicing the bearings. As this is a 40+ year old engine, I felt it was cheap insurance, plus with the heavy steel conrods throwing that weight back and forth, these bolts have more than seen their fair share of stress. Removal was as simple as bracing each conrod in the vice and hammering out the bolt. To install, I'll use my shop press.
Each conrod and related parts degreased for a second time and ready for sleeve bearing and bolt installation.
How I organize each valve and related springs.
Here's a couple photos of the rocker arm half-shafts.
Intake and exhaust side-by-side. Note the differences between the oil passages - be sure to reinstall these correctly!
The rocker arms have been ultrasonically cleaned and everything is now organized and ready for dry-film application and then reinstallation.
While I had the ultrasonic heater working, I chose to try it on the dirty rear main seal cover...
...And it worked like a charm! The dirt wiped off easily.
I moved onto breaking down a fuel injector to see if I had to live with the pre-cut fuel lines.
All of the fuel injector fuel lines are showing cracks; I have no intentions of reinstalling these in this condition.
I carefully cut the fuel line away and found what I was hoping for - a barbed connection! This allows me to use my own hose clamp solution. I went ahead and got a bunch of "Oetiker" stepless ear clamps (newer BMW's use these as OEM); I will be using these to secure the fuel injector to the fuel rail.
I also proceeded to remove the large rubber ring which secures the injector to the manifold bracket. There is a circlip that holds it in place (kind of).
Here, you see that the circlip only keeps the rubber ring to one side of the large indent in the injector housing. I had to cut through the rubber ring to remove as well.
The small injector seal actually broke in two when I began to remove it, due to its brittleness.
The injector after a bath in the ultrasonic cleaner and a zip through the dremel to remove the surface rust. I'll take a clearer picture in my next set...
Until next time...MTF.
Mike