Absolutely, that's the main reason the blocks will flex and crack on the high horsepower single 600cc engines.
No the rocker covers leak because shaved gorillas use a power driver to do up the retainers way too tight.
This deforms the cover where the screws go through and chops up the cork gasket .
They are done up to 8 PSI which most blokes can do with their old fellas
I have knocked the dents out of dozens of them then done them up properly and they work just fine
The front 4 crankcase bolts work loose on the older models but it s not hard to tighten them and if you lift the flywheel a couple of drops of blue loktite cures that problem
Biggest problem for me is the massive number of different configurations of the counterweight .
This is a result of penny pinching by the mower companies .
I had one come in with over 3,000 hours on it as it was used to mow a cricket pitch + the spectators area every week for the cricket season then just the spectators section for the scoccer season .
This one had a forged crank
All of the others I have worked on have had cast iron cranks so my guess is it was designed to have a forged crank then to cut costs they switched to the substantially heavier cast crank which threw to balance way out ..
I get a couple of cams in every now & then but it is on par with all of the 31 series B & S deceased cams but the Kohler is a 2 hour job start to finish & the Briggs is 2 hours just to get the engine out .