801 injection pump rebuild no start

801 Diesel after sitting 8 years. An experienced mechanic found rust in the old fuel while draining the tank filters and pump body, and decided the pump needed a rebuild. Then mechanic went home to Washington.

Pump rebuilt, I show up to install.

Rolled engine until #1 push rods loose, set it to 20 degrees BTDC on the flywheel, pump gear looked right with the larger segment of the gear/drive facing the engine (per a different post here on YT). Pump went right on, pump timing marks aligned in the window, installed. Lines cleaned, installed, purged of air, fuel up to the injectors, air bled out several times.

Cranking with half throttle (cover handy at intake to keep from running away), glow plugs working. NADA. Engine breath out the exhaust, but no smoke.

Gave it a whiff of starting fluid, it seemed to pick up in cranking speed, but no start. With no sign or smell of fuel in the cylinders, ether is pointless as well as ill advised anyway.

As I understand engine timing, and the way this engine was timed, there's no chance it could be 360 out, right? If I accidentally had cylinder #1 at the TDC #4 cylinder (1-2-4-3), then pushrods on #1 would be tight as the exhaust valve would be closing, and the intake opening, right? So that's out of the way.

Then the pump gear drive plate with its groove cut through, rotates at half engine speed, and would always be in the same phase position....would always be in the unique position when at #1 TDC. So when the pump with its eccentric shaped drive key fits right on the drive plate correctly, that's the only way it could go...confirmed by the timing mark in the pump window aligning.

So, throttle in half position, cranking, fuel spurting at injector nuts, then tightened and more cranking.

Any ideas? I'll keep air bleeding and cranking but at what point do I start to investigate other issues?

Is the cranking speed at least 200 RPM? If not don't expect it to start as both compression heat and pump delivery will be less than ideal for starting. There is a chance the pump is 180 degrees out of time IF the drive shaft is installed wrong, but the timing lines inside would not align UNLESS the retainer timing ring was installed wrong also. I'd make sure the starter and battery are both in good condition first..

Any engine that sat for 8 years is very likely to have rings tha tare stuck on the pistons and that causes low compression and low compression can cause a no start like your having. On the engine I am not sure of an easy way to put ATF in the cylinders but if you can do so it would help and then let it sit a few days. Years ago I had an A/C XT190 with a locked up engine due to the pump going bad and I got it freed up using turpentine. And go it running very well but was way to much tractor for my small place so I sold it

It seems the injector system is about foolproof to assemble correctly....interesting that the pump rebuilder could have put a piece in 180 out. I'll keep that in mind.

I think we'll pull start it, as the cranking speed is not great, and the compression could be a bit dozy.

Pull start it to see if it will run, my 881 had been setting in a barn for over 15 years and after replacing the umbrella seals and filter (rust in it also) it took a couple light shots of either to get it to start and run, you can't pull start a SOS.
Several years ago I had the pump rebuilt on a 871 I had, we had a hard time getting it started and it wouldn't rev up without popping and missing. Finally figured out the pump shop had installed the timing advance plunger in backward, corrected it and the tractor ran great.

The owner also just told me that the engine had been rebuilt because it threw a rod. When I asked if it had been run since rebuild, he said no.

So I really suspect that the compression issue and cranking speed is one good reason it doesn't just start.

Wish I'd known about the rebuild...would have done more lube before turning it....wondered why the valve cover gasket seemed new...

Will check for oil pressure while cranking, then pull start it.
Still I wonder why I'm not getting the typical unburnt fuel vapors and smoke stink...

With the engine being rebuilt the injectors are most likely air locked, no smoke out of mine until just before it fired up.