Re: 1976 BMW 530i "Eleanor" rebuild project
Posted: Tue Jan 07, 2020 11:28 pm
Continuing the project...
I got some boxes and put the parts inside. At least it gets them off the garage floor (man...I REALLY need some proper storage!).
I moved on to removing the injectors. Because the harness connectors are a PITA to remove, I opted to remove the injectors, manifold, and wire harness en-masse. I'll deal with the injector plugs on the bench.
The throttle cable lever point on the block was in the way of the auxiliary air valve harness connector. I took my flathead screwdriver and gave the linkage ball joint a light tap to remove.
The throttle linkage is removed. No doubt the solid pedal to throttle body connection is why the pedal feels crisp and responsive, unlike cabled setups.
Here's the auxiliary air valve connector in question (white cable). Needs to be removed in order to remove harness from engine.
The entire injector assembly removed and laid out. Note that this is the only system that connects to the glovebox ECU. If this were Motronic, the harness would be more extensive, as many other components also report to the Motronic DME.
Now, the left-side is much clearer, sans harness and injectors. Moving onto intake manifold removal.
While the top manifold nuts are easily-accessible, the lower nuts are blocked by the coolant pipe. I removed the pipe and while it has some surface rust...
...I was shocked to find that the pipe's interior was spotless! This gives me hope that I can put the pipe into rust removal solution and reuse it. I will measure the wall's thickness with my micrometer however, to ensure there is enough material there to continue serving as a coolant pipe.
In order to remove the #1 cylinder lower intake nut, I needed to remove the thermostat housing.
The thermostat housing is foremost center-photo. It is held on by three nuts. This needed to be removed to access the #1 intake nut.
And, just like the coolant pipe, I was also surprised at the condition of the coolant temp sensor and thermostat housing interior.
The cleanliness extends into the cylinder head coolant void. Time will tell as to how the cast iron block passages look however.
The intake manifolds are now removed, exposing the intake valves.
...And the valves are clean as well...
Cylinder 2 intake looks good...
And cylinder 6 looks great as well. I started to wonder about WHY the engine died during ignition timing, as I have not as of yet, seen any physical damage that could explain it.
Now, with everything other than the starter removed, the head is largely clear for removal.
As I was unbolting the rear coolant passage cover, the bottom bolt was needing excessive torque to turn. I decided to stop and put the other two bolts back in before I snapped the bolt in the cylinder head. Removal of this wasn't necessary to remove the head anyways.
Once upon a time, I would have muscled the head off the block, but with my back being what it is, I opted to use the engine hoist to remove the head for me.
Removal took a surprising amount of force. The block itself began lifting with the head, but finally a POP occurred, and the head and block were now separated.
The cylinder head is lowered down but is still resting on the hoists chain in mid-air.
At first blush, I didn't see any cylinder leakage, but I did/do note that the gasket around cylinders 4-6 has what looks like oil seepage beyond the oil channels.
Wanting to see if this was the original cylinder head, I looked underneath, and it appears that I have a newer style head. The old style had much wider coolant passages, but was weaker generally. My thoughts are that either the PO or the first owner needed to replace the head due to reactors cracking the metal. I did receive the reactors as part of the sale, so they are sitting in a box.
The block, sans gasket.
One issue of concern is that cylinder 3 shows vertical scratches that can be felt with a fingernail. Also, none of the visible bores show any crosshatch left. I have a bore dial gauge and outer micrometer set that I'll use to determine if the bores are within spec for diameter and roundness - I will need to make a decision if I need to move up to oversized pistons, or, if roundness is true, then if I can limit removal of bore wall material to continue using the existing pistons.
But, the next step will be to remove the oil pan. I have a plastic "drip" tray underneath to keep my dirty garage floor not more dirty.
That's all for now. Next steps will be disassembly of the block and internal rotating components. I'll also be using the garage dishwasher to clean individual parts.
I got some boxes and put the parts inside. At least it gets them off the garage floor (man...I REALLY need some proper storage!).
I moved on to removing the injectors. Because the harness connectors are a PITA to remove, I opted to remove the injectors, manifold, and wire harness en-masse. I'll deal with the injector plugs on the bench.
The throttle cable lever point on the block was in the way of the auxiliary air valve harness connector. I took my flathead screwdriver and gave the linkage ball joint a light tap to remove.
The throttle linkage is removed. No doubt the solid pedal to throttle body connection is why the pedal feels crisp and responsive, unlike cabled setups.
Here's the auxiliary air valve connector in question (white cable). Needs to be removed in order to remove harness from engine.
The entire injector assembly removed and laid out. Note that this is the only system that connects to the glovebox ECU. If this were Motronic, the harness would be more extensive, as many other components also report to the Motronic DME.
Now, the left-side is much clearer, sans harness and injectors. Moving onto intake manifold removal.
While the top manifold nuts are easily-accessible, the lower nuts are blocked by the coolant pipe. I removed the pipe and while it has some surface rust...
...I was shocked to find that the pipe's interior was spotless! This gives me hope that I can put the pipe into rust removal solution and reuse it. I will measure the wall's thickness with my micrometer however, to ensure there is enough material there to continue serving as a coolant pipe.
In order to remove the #1 cylinder lower intake nut, I needed to remove the thermostat housing.
The thermostat housing is foremost center-photo. It is held on by three nuts. This needed to be removed to access the #1 intake nut.
And, just like the coolant pipe, I was also surprised at the condition of the coolant temp sensor and thermostat housing interior.
The cleanliness extends into the cylinder head coolant void. Time will tell as to how the cast iron block passages look however.
The intake manifolds are now removed, exposing the intake valves.
...And the valves are clean as well...
Cylinder 2 intake looks good...
And cylinder 6 looks great as well. I started to wonder about WHY the engine died during ignition timing, as I have not as of yet, seen any physical damage that could explain it.
Now, with everything other than the starter removed, the head is largely clear for removal.
As I was unbolting the rear coolant passage cover, the bottom bolt was needing excessive torque to turn. I decided to stop and put the other two bolts back in before I snapped the bolt in the cylinder head. Removal of this wasn't necessary to remove the head anyways.
Once upon a time, I would have muscled the head off the block, but with my back being what it is, I opted to use the engine hoist to remove the head for me.
Removal took a surprising amount of force. The block itself began lifting with the head, but finally a POP occurred, and the head and block were now separated.
The cylinder head is lowered down but is still resting on the hoists chain in mid-air.
At first blush, I didn't see any cylinder leakage, but I did/do note that the gasket around cylinders 4-6 has what looks like oil seepage beyond the oil channels.
Wanting to see if this was the original cylinder head, I looked underneath, and it appears that I have a newer style head. The old style had much wider coolant passages, but was weaker generally. My thoughts are that either the PO or the first owner needed to replace the head due to reactors cracking the metal. I did receive the reactors as part of the sale, so they are sitting in a box.
The block, sans gasket.
One issue of concern is that cylinder 3 shows vertical scratches that can be felt with a fingernail. Also, none of the visible bores show any crosshatch left. I have a bore dial gauge and outer micrometer set that I'll use to determine if the bores are within spec for diameter and roundness - I will need to make a decision if I need to move up to oversized pistons, or, if roundness is true, then if I can limit removal of bore wall material to continue using the existing pistons.
But, the next step will be to remove the oil pan. I have a plastic "drip" tray underneath to keep my dirty garage floor not more dirty.
That's all for now. Next steps will be disassembly of the block and internal rotating components. I'll also be using the garage dishwasher to clean individual parts.