rScotty
Super Member
- Joined
- Apr 21, 2001
- Messages
- 8,257
- Location
- Rural mountains - Colorado
- Tractor
- Kubota M59, JD530, JD310SG. Restoring Yanmar YM165D
I don't have access to my service manual. However, I think it is binary; below a coolant temperature of 120°F, the timing is retarded 2°. Above a coolant temperature of 120°F, it is advanced by 2° back to design timing.
It is done internally to the hydromechanical Bosch Injection Pump. (As I said, I don't have access to the service manual. It's in our storage container since we moved to Idaho.) If I were designing the actuator I would have it fail to normal timing. 2° timing change is miniscule since I think this is just a "rule beater" to satisfy the EPA. during Tier II certification. I notice no difference in performance and the exhaust is invisible after startup.
That's interesting about the "invisible exhaust" on your TD95D. I think you are saying it runs very clean. So does the old tier II motor on our JD310. Those Tier 2 engines only had to meet minor EPA standards at the time, but ours has a natually has clean exhaust - and it is very economical to run in spite of it being 90 hp.
It makes quite a contrast to our 2008 Kubota with the emission equipment designed for the Interim Tier 4 regs - which are NOT the same as the final Tier 4 regs. Nobody would call that exhaust invisible. It's black. Interim Regs were all about NOx & not about soot.
That engine has horrid exhaust & less HP than the JD but uses twice the fuel. Getting a whiff of its exhaust will make your eyes cross, but that is what the EPA standards required at the time. Still, it's been a reliable engine in spite of the dirty exhaust
Someday I'd like to find a way to study up on exactly what the "engine computer" does on our Tier 2 JD.
rScotty