JD 240 engine vibration problem

I have the afforementioned JD 240 skid loader, 1700 hours on it, bought it about
300 hours ago.

The engine, at idle especially, vibrates excessivly.

I mean sitting in it you cannot focus your eyes.

1. The electric lead from the alternator broke off.
2. The ears on the radiator (solder joint) failed , I re-soldered.
3. The exhaust had been re-welded before I got it.
4. The rear engine mounts were bad (I replaced them)
5. The (2) hyd. cooler lines failed from abrasion.
6. I checked the valve lash, it was slightly worn, but nothing
major worn, but did re-set while in there.
7. Finally, the remote oil drain line failed from abrasion this winter, luckily
I was pushing snow into a bank, backed up and saw the oil stain, headed
for the barn, when the Oil pressure got to around 10 psi I shut it off.
(just missed getting in inside). But removed all that, put in a simple plug on the
pan, and primed it with the injector pump solenoid unhooked. Appears I missed
a bullet here. 'Bout soiled my pants though....

One older JD tech told me to slightly move the injector pump from the mark
(either way) I tried to get a wrench on the bolts, but they are quite cramped in there, and wanted to round as well.

Is there a special wrench ?
Or is there a known problem ?

I don't like full throttle until warmed up, and don't like
shutting down without a bit of idleing to cool down.

BTW JD phone help was NO help, wanted me to take to dealer only.

JD 240 engine vibration problem