John Deere 720 Diesel cranking engine start

[weaver1]

So this is my first tractor I've ever purchased and I went in knowing it was a project but the previous owner (a good friend) drove it into the barn and there it sat for 8 years until I purchased it and it was pushed onto the trailer. Needless to say, I was probably in over my head the second I pulled out of his driveway so I purchased a good service manual and have done as much research as I pretty well could, along with the advice of a few very sharp guys on a couple Facebook groups.

Its a 720 diesel, serial number 7223440

Previous owner ran bio diesel in it and parked it for 8 years...It turned bad. REAL BAD! LOL So I had to clean the entire fuel system with e85. Which I found ironic that corn fuel cleaned soy fuel Ha! It took some time, and the only area I feel like I might not have 100% good is the injector pumps as I don't have the capabilities to tear them apart and put them back together to the specifications they should be.

I rebuilt the distributor, tested for spark, and we're good.

Rebuilt the carb. It was giving me the fits but I think I have it straightened out...

I went to fire the Diesel engine and as I engaged the cranking engine clutch it slowly pulled the pony engine down pretty hard. Almost to the point of killing it. The diesel gave out a few puffs of white smoke which led me to believe I have fuel. But it never cracked over. I have bled the 3 points in the fuel system as the service manual says.

To all you folks out there that have experience working with cranking engines...what do I need to focus in on?

Is my pony weak?
Load settings on my carburetor?
Fuel System on the diesel?
Somewhere else that I'm not thinking of??

 

[rrlund]

Are you using the compression release? Get it spinning with the compression released,then slowly release the release. (Repetitious
ain't it? LOL)

 

[RogerinIowa]

Pull start it for the initial starting.
Save the pup for easier starts.

 

[960]

You are going to have to clean injector pump 100% as well.

 

[Blksmok]

I would try to pull start it first to determine if the Diesel engine will run. If it doesnt start with a pull the pony engine will never start the Diesel engine. It is
very common for the rack on the injection pumps to stick upon sitting and definitely if is has bad biodiesel in them. This will not allow the pumps to open
.

 

[buickanddeere]

A starting engine hitting on all four cylinders will wail over the diesel under compression without slowing .
Odds are one set of points, one coil one plug wire or one plug has failed . This will take out two cylinders . Two plugs fire at the same time.
As previously asked. You are rolling the diesel over without compression and fuel until oil pressure is obtained ?