As I wrote earlier, the block was taken by m20b25. I bought the entire bottom of the motor assembly with the e34 for little money, plus I got the Getrag260 box from her as a bonus.
I decided to assemble the engine “in an adult way” – no pouring of old dirty parts from engine to engine, as many people do quite often. We prepare everything carefully.
We properly wash the block from all the garbage that has stuck to it over the years of operation.
We carefully inspect it for cracks (on a clean one it is much more convenient to do this) and all sorts of defects. We check the play of the intermediate shaft – if it dangles, you need to change the bushings. You can order repairs, but they take a long time and it’s not a fact that they will come at all. Here are the order numbers:
Large bush: 11111280863
Small inner bush: 11111264196
Or machine them out of bronze. In any case, they will need to be transported along with the block and the intermediate shaft, because. after pressing in, the bushings turn under your shaft. The shaft also needs to be ground if there are defects.
Here is a photo of them, so that it is clear what they are talking about (the photo is not mine, everything turned out to be in order for me)
If everything is OK and there are no cracks between the cylinders, the cooling jacket, the holes for the cylinder head bolts and there are no hellish scuffs in the cylinders, we are taking it to the turner. Do not build illusions about the ideal state of the cylinder-piston group. Even if it seems to you that the pistons in the cylinders do not hang out, the cylinder mirror is not damaged, the hone is present and everything seems cool – 99% that it is not. Miracles do not happen, unfortunately, especially if the nominal size is on the pistons)) 1% – this is if someone has already made this block before you – sharpened and set the repair size of the pistons, did everything well and drove a little.
In general, what we could see for ourselves – we looked, then it’s up to the turner – he already measures the taper, ovality and draws conclusions, it’s worth sharpening this block or into scrap metal and looking for a new one (if the turner is adequate, many just don’t care).
I sharpened this block in +0.5 to 84.5 mm (for ordered pistons). 0.15 mm was removed from the plane of the block. It is better to have the pistons that you will install in this engine immediately and give them to the turner along with the block. Someone will probably say – what for, you just need to take normal pistons and everything will be fine with the geometry. Maybe so, but you won’t lose, and so each cylinder is sharpened under its own piston and the pistons are numbered. Even if in the end the diameter of all cylinders matches up to microns, it’s better to be careful ))
We give the turner the hard-earned money, we take the block.
Be sure to wash it again! Very carefully, not forgetting the cooling jacket and all oil channels! After washing, be sure to dry (wipe, blow with a compressor), because. bare cast iron likes to rust, and we do not need it at all.
Again we pay attention to the oil channels – for cleaning we use round brushes or a ramrod (I don’t know what to call it correctly).
Not everything is washed off with water and chemicals, and quite a lot of dirt remains in the channels.
Washed, cleaned, now paint the block.
I tried to find information about who painted the block with what and how long the coating lasted, but I didn’t find any answers. I decided to experiment with Motip 04092 paint in a can.
The manufacturer promises that the paint will live happily ever after on the block, despite gasoline, oil, temperature and other hellish conditions. We’ll see.
We go through all the threaded holes with taps – something like this
Like everything, the block is prepared.