HydroTek

CCW starter is correct starters are clocked looking at the drive end Pull your starter off (3 bolts) and count the teeth

Housing needs to come off and be either welded up or bushed -- then line bored the pin is not available -- but can be made from 4140 the brass bushings would have to come from some place like McMaster I have a 656 that is in a similar shape so sometime when I get a chance it needs this

20 is a little light for those 3/8" bolts 35 would be more like it

This have the pto buttons on the rear of the tractor ?

4140 steel would make good pins should be a common diameter if the holes are worn -- then larger pins or have the bushings replaced (welded on)

Far as I know the only difference was the inpeller non turbo used the short vanes turbo used the long vanes

I used the pilot bearing puller when the flywheel was left on the engine -- a slide hammer can also work -- put the hook in the hole and drive a punch to wedge the hook in -- then just a couple of pulls and the bearing is out Yeah that AI stuff will be part of the downfall of the human race -- think Sky Net and Terminator or Matrix Never did I ever torque those bolts -- tho I am sure there is a spec -- likely be in the engine book

104189A1 should have 9 teeth that starter fit most of the gas models of that tractor type - so 454 - 574 You dont have a rebuild shop around ? -- the other starter is used on the Hydro tractors

Put some brass on the key , then file the key to fit snug in both parts

The metal is getting brittle , those springs get stretched quite a bit guess you "know your stuff" now tho in changing springs -- LoL

Talking about the pin inside the pump ? or the lever on the outside -- pictures would help with the guessing

Yup , regular silicone releases acetic acid as part of the curing process -- the gray and some of the black uses a different curing method Also could use Lexel clear if you dont have the 847 get the Lexel at the hardware store

I use 3M 847 -- best stuff you gonna find can be used as a contact adhesive so clean both surfaces well of any oils or dirt then smear a coat on each side -- your gloved finger works best -- or wear the brown finger of success let dry until tacky to your finger -- only takes a few minutes then press the parts together -- correct the first time -- this 847 has a really tight grip

That tractor only sat in the water a short time -- but it sat a long time with moisture in the bell housing -- the rust evidence points to that conclusion The metallic clutch disk stuck to the flywheel is from sitting with the water (salt water ?) in there A good cleaning and use a sanding pad on your die grinder to get most of the rust knocked off the flywheel surface -- new clutch and throw out bearing -- dont forget the pilot bearing -- and transmission input bearing and seals

Also -- throttle needs to be open when checking compression

Sounds like the splines are stripped out -- this tractor have the TA or reverser ? pictures of the carnage please when you get it apart

Anything else powering with the key ? gauges, blower, radio, grain monitor, etc.

Bumper spring just takes the surge out of the govenor sounds more like you have a carb issue worn throttle shaft bushings

Gonna be tearing into the two speed tell us what you find when you get the clutch pack out -- pictures , we like pictures Shaft seals or high side piston seals most likely

Disconnect the cylinder cap the base end port engage the remote to pull the cylinder in -- if the packing is leaking the cylinder will extend instead of holding position Oil leaks past the packing and enters the base end of the cylinder , causing the rod to extend even tho the oil is directed to contract the cylinder . This is because the area of the piston on the base end is larger than the area of the piston on the rod end .

Likely the pump then

So. steering is weak ?

pry bar and see if you can turn the engine from the pump drive gear

Just as well get that pump straight from Hy-Capacity https://www.hy-capacity.com/hydraulic/mcv-pumps/pid4777/mcv-hydraulic-pump/#relatedproducts I dont see the gear offered there yours has the straight gear ?

Can use a remote to check standby just need to remove the signal (sense) line from the compensator and plug the line -- leave the compensator open Start the engine , then engage the remote -- 600 psi gauge there may be a pressure surge at startup if the gauge is exposed to remote pressure