My Cub Da-debt

[john hall]

Not that anyone would use it, but is the deck hooked up to a PTO or is on there just for looks? I can see where this was a project not to keep an expense record on!

[mowerpower2u]

Originally Posted by J-Mech

The hydro wouldn't handle more than 3500 RPM's? A stock hydro turns faster than that. Why did it turning so fast blow the dipstick out? How exactly does a high torque affect a hydraulic pump?

You made the oil passages larger? Which ones? How did you modify the check valves? Got any pics of what you did to the pump?

With the torque of the engine and speed of how fast it revved the hydro would not get the fluid fast enough through the charge pump.It was turning faster than it could supply fluid to the pistons and causing cavatation which filled the fluid with bubbles and caused internal pressure and blew the fluid out. Machined out the oil passages on Part D & E in the picture and i added a second spring inside the originals to make them stiffer.Replaced the springs on Part C with stiffer ones and bored seat a little where the ball fits.Milled out oil passeges on Part 35 where charge pump mounts to it. Replaced the charge pump spring in Part F with a softer one.(NOTE:After i first did all the mods,The hydro would not work at all until i changed this spring with a weaker one)

[mowerpower2u]

Originally Posted by john hall

Not that anyone would use it, but is the deck hooked up to a PTO or is on there just for looks? I can see where this was a project not to keep an expense record on!

Deck does work.

[Sam Mac]

What did you do to deal with the rotation of the engine? Kinda surprised you used a 1440 with the Hydro Gear pump rather than something with a Sundstrand for your starting point.

[mowerpower2u]

Originally Posted by Sam Mac

What did you do to deal with the rotation of the engine? Kinda surprised you used a 1440 with the Hydro Gear pump rather than something with a Sundstrand for your starting point.

I reversed the rotation of the engine by using a custom made gear drive and having a custom camshaft casted and ground for it.Also the starter drives from top rear of the engine now. I started with the 1440 hydro because had a new one and i knew they were tough.

[olds45512]

heres a video i found on youtube.

https://www.youtube.com/watch?v=8LXFSLK3otM

[mowerpower2u]

Originally Posted by olds45512

heres a video i found on youtube.

https://www.youtube.com/watch?v=8LXFSLK3otM

That was at a Chevy Dealership about a year after i built it. It will run fast that but i had it programmed to about 1/4 throttle on that day so the kids could drive it too.

[ol'George]

Some other questions please:
On the SBC, IIRR some marine engines turn reverse rotation did you use their
cam/drive/ gear setup?
Why did you change the engine rotation?
the hydro's are set up to turn either way by reversing the charge pump.

[mowerpower2u]

Originally Posted by ol'George

Some other questions please:
On the SBC, IIRR some marine engines turn reverse rotation did you use their
cam/drive/ gear setup?
Why did you change the engine rotation?
the hydro's are set up to turn either way by reversing the charge pump.

Yes,Some marine engines run reversed.They use several variations of timing drives,distributor gears,camshafts and reversed starters. There wasn't a set up for what i wanted to build.I used a two piece gear for the timing that when the engine is turned counter clockwise the camshaft turns clockwise.The camshaft has a reverse cut gear where the distributor mates and distributor gear is a stock.The distributor still rotates clockwise but has a different firing order. I wanted certain lift and duration also.After talking with several cam manufactures and techs,There wasn't a cam made like this,So after many phone calls one agreed to have it cast for me and grind it to my specs.
I changed rotation not only for hydro but also as where the deck could be belt driven and in the right direction.

[Sam Mac]

Guess I'm just simple, I would have turned the engine around and run the pump from the front and the PTO off the flywheel. Glad you had fun doing it the hard way. Anyway that said cool build.