Since most of the parts for the engine were lying ready on the shelf and blocking storage space, why not just put everything back in and on the block.
We pulled the bare block which was “stored” in the chassis and got it back on our engine stand … time for a final cleanup of the interior and the complete oil circuit. The camshaft with the plungers come in first (sorry that we have no pictures of this, even when we got the camshaft in and out 3 times, due to various reasons), followed by the oil spray nozzles under the pistons. Time for new main bearings …
After the bearings were in, let’s put the crankshaft in. The crank is a heavy bastard, even without the counterweights … or our engine stand is just to high to carefully lift the crankshaft with two people into the block. Easy task for the crane, but wait … find the error … 🙄
Main caps on, bolts in an then it’s time for some serious tightening. The needed torque on the main caps and on most of the other parts which will follow feels like the bolts (mostly fine threaded M20s) will shear off any second 😐
The counterweights are bolted to the crank … but before mounting these, let’s put them on the scale and do some math about the forces the bolts have to hold. The heaviest counterweights have around 7kg, let’s assume 3000rpm and the weight traveling at a radius of 12cm around the crank … thus the weight travels 0.75m per revolution and 37.7m per second … physics tell us that the centrifugal force calculates as: F=m*v²/r … resulting in 82.9kN … or ~8.5tons pulling on the crank .. there are 6 weights and we will attach 8 pistons with steel rods to that same crankshaft 🙄
Let’s not further think, what will happen when one of these parts comes of … oh, and the centrifugal forces are proportional to the square of engine speed.
After installing the pistons, all the parts were “in” the block. 3 pistons missing in the picture 😉
To close the block, we will just put the oil pan on. Actually not. Since we wanted a low center of gravity on the tractor, we are putting in the engine nearly as low in the chassis as we can. Without wanting to build a complete new oil pan, we just shortened an original pan. No problem, until you want to install the oil pump with the original suction tube …
Just a quick check and adjustments for clearance and we were fine.
In fact we came a little forward to make the engine race-ready and were meanwhile advised several times not to go with the original oil pump and setup, and will now go with an external oil pump. The newly build suction tube might become a nice candle holder 😛
Putting the cylinder heads on should be no big deal. Well, it is not, but there are a lot of parts going in the heads after installation and again lots of bolts to torque to the specifications.
Just get the timing gear on in the right position and the engine is back together. No worries, with the turned down pistons, the engine is a free runner (the valves won’t touch the top of the pistons in any position) and we don’t need to install the timing gear before the installation of the valve train.
All nice and shiny …
… hard to believe, regarding the state the engines were in before, and that we had to disassemble this particular block with a sledge hammer.
Time to move on with the auxiliary drive and work on the chassis, which will be covered in future episodes.