Oil & Fuel NH TC33D cranks but slow to start

[FarmerGerald]

Bought a used TC33D a few months ago--and tractor cranks but slow to start. I did a post here and got help with glow plugs and installed new glow plugs and then later installed a jumper wire with push button to insure that the glow plugs were getting current and getting hot. Tractor cranks fine--but even with new glow plugs and hot wire to the plugs I still have to crank several times before tractor starts up. Not a battery issue, not a starter issue, new glow plugs, new fuel filter. Any ideas on what I need to do next would be appreciated. Clock was stopped when I got the tractor with 600 hours on it--so no idea how many hours on the tractor-BUT everything works fine on the tractor. My only issue is slow starting. Unclear to me if/how to adjust timing on the injectors, etc. or even if this is an issue. Any ideas or suggestions would be appreciated.

 

[FarmerGerald]

And--- forgot to include in my cranking issue post-----once the tractor does start--after about 6-10 tries---it runs fine.

 

[Roadworthy]

If you've not done so be sure the air cleaner is clean and there are no obstructions in the air path.

 

[FarmerGerald]

If you've not done so be sure the air cleaner is clean and there are no obstructions in the air path.

Spent most of the day on this tractor project.
I do have new air filters and have checked air flows since when I installed the new glow plugs I had to remove the entire air filter assembly to get to them.
I have tapped into the wire to the fuel solenoid to check that I am getting 12 volts and that the solenoid should open to allow fuel to the injector pump.
Ditto the wire to the glow plugs.
Interestingly enough, 12 or so volts to both the glow plugs and the solenoid with the ignition switch in the start mode.
However, as soon as I start cranking, the voltage to both the glow plugs and the fuel solenoid drops down to around 9 volts.
So, I took my brand new RV battery (fully charged) and hooked it up to the tractor battery via heavy duty jumper cables and tried to start again.
The tractor battery is practically new and I have just carried it back to NAPA to get them to verify it was good since only about a year old and from NAPA.
Battery checked out good.
With the extra battery---
A little better since the voltage to the plugs and solenoid started at 12.5 or so volts and only dropped down to 10 volts while cranking and after several cranks the tractor started. After running a few minutes voltage was up to 13.5 volts (via alternator) to the solenoid valve.
I don't have a reference point to see if my starter is spinning the engine as fast as it should but seems like maybe I have a starter issue with it dragging down the voltage that much while the starter is cranking the engine.
But, I now know the solenoid is allowing fuel to the injector pump and that in the engine not running and the switch on, I have good voltage/current to the solenoid and the new glow plugs.
Any ideas/thoughts/suggestions?
Gerald

 

[ruffdog]

And--- forgot to include in my cranking issue post-----once the tractor does start--after about 6-10 tries---it runs fine.

Here is your first glow plug thread:

https://www.tractorbynet.com/forums/new-holland-owning-operating/420260-glow-plug-timer.html?highlight=#post5605336

 

[ruffdog]

Have you bypassed your battery cables yet? Just go from Bat - to the engine block and Bat + to the starter lug with jumper cables. Then try to start it. If it is better, something is wrong with your battery cables. If that doesn't work, check compression.