Hard-starting 510d

[subybaja]

My dad's got an old mid-80's John Deere 510d that doesn't start worth a darn.
It's gone through 3 starter motors and 4 relays in 3 years.
It's got an I4 non-turbo diesel, with no glow-plugs.
The engine was rebuilt by the local college's heavy equipment program. It has had several hundred hours since, but never started well. If it turns over, it seems to fire all right and run well, but it's always been a pain to get turning.

Both starters are in to the shop being tested right now. The cables are new, and the battery tests good (950 cca on an inductance tester).

This last weekend, it was 13*f. He plugged in the block heater, and also threw a propane Tiger Torch under it. With the block hot to the touch, and the starter removed, a firm push on the ring gear would turn the engine. When it cooled down later it wouldn't budge with a prybar. 15wt dino oil, BTW.

The guys at the motorcycle forum who sent me here suggested
-injector timing
-valve clearance
-flywheel or rod bearing overtorque.

Injector timing shouldn't have anything to do with cranking
Valve adjustment- maybe?
Bearings...after a few hundred hours, shouldn't they have loosened up?

So, I hate to be the noob jumping in with "My stuff's broke", but any ideas?

 

[jenkinsph]

I'm going to take a swipe at this,
Most of the older backhoes had a choice between either one battery for mild climates and dual batteries for colder climates. In both cases the batteries were group 31 size, with dual batteries you could be approaching 1500 to 2200 amps. That is quite different from the 950 amps you mentioned. To deliver that much power your terminals and connections need to be very good. Deeres' group 31 batteries are about 750 cca but the DieHard Platinum Plus batteries are 1100 cca, these are made by Odyssey Battery and are first rate in my book.

Don't know enough to help with the bearing and valve adjustments but that seems like a lot of difference to me between warm and cold.

Question, how does it crank in the summer months?