LD/LDT vs LDS Hydraulic heads

[rustystud]

I think I need to explain the reason I said that the amount of fuel has nothing to do with timing. A given amount of fuel has a set amount of potential energy. So when your going down the road with "no" load you only need a small amount of fuel (energy) to keep the engine turning at a set RPM. When your going down the road under "full" load at the same RPM you need a lot more fuel (energy) to keep the engine turning. You didn't increase the timing just the amount of fuel (energy) needed to keep the engine turning at the set RPM.
Another way to put this is by an example I learned in trade school. They put a small amount of fuel in a tube and lit it off. The explosion was considerable but not near the same as when they put more fuel into the same tube and lit it off ! Now that was an explosion ! Same amount of "space" just more fuel (energy) . They just increased the amount of potential energy in that same space which translates into more "power" or "push" or "force" against the piston.
So by increasing the amount of fuel injected into the cylinder we are just increasing the "force" against the piston, allowing it to "push" harder against a heavier load.

 

[Floridianson]

My thought on the injectors was maybe the LDS also runs more advanced timing. If the button is really a timing button then it would seem we could advance a degree or so. The buttons on the 90100A HH I have seen is a 03 and don't know what timing button is on a LDS head. Think there was a thread and the LDS IP lower end was set up with lighter springs to bring the advancement in quicker.

 

[rustystud]

My thought on the injectors was maybe the LDS also runs more advanced timing. If the button is really a timing button then it would seem we could advance a degree or so. The buttons on the 90100A HH I have seen is a 03 and don't know what timing button is on a LDS head. Think there was a thread and the LDS IP lower end was set up with lighter springs to bring the advancement in quicker.

I'm so sorry I forgot to answer your question from yesterday ! I got caught up in my explanation to "squirt truck" .
I'm not sure if it would change the timing since it seems the buttons main purpose is to take up the clearance like a "selective thrust-washer" does in a transmission. Of course they call it a "timing button" so maybe it does change the timing. I need to research it some more.

 

[Bill W]

Dang!,..My head hurts...

 

[gimpyrobb]

Think there was a thread and the LDS IP lower end was set up with lighter springs to bring the advancement in quicker.

Rayzer had me send him some LDS timing springs for one of his IPs. Maybe he could shine some light on the difference.

 

[gimpyrobb]

http://www.steelsoldiers.com/showthread.php?131248-Lds-Injection-Pump-On-Ldt&p=1623714#post1623714

 

[Floridianson]

What if what they call the timing button was just different thickness and would not affect timing per say. BUT! Would a thinner button allow the plunger to sit lower on the down stroke of the tappet but deliver more CC shot?
Jason do you still have the button from the LDS head?

 

[Theodgeman]

I would like to know what size the plunger and barrel is OD and ID is on the LDS VS the LDT. I know if you change the pop of pressure of the injector it will change the timing. This pump does not have delivery valves like a P pump so I think that the button thickness could have a lot to do with adding more fuel or the delivery passages in the hydraulic head. Timing can add power but most of the time the plunger/barrel bore will change to allow more fuel like on a P pump. I would love to pick up a few of these pumps to play with.

 

[Floridianson]

I do not know if they would run better with a little advancement. They will run real good just getting a pyro and turning the fuel up. I have run the inner nut till it bottomed out turning up the fuel to it's real max. The smoke never cleared and there are less mosquito's around plus the cylinder temps would climb fast.

 

[Theodgeman]

Advancing the timing will help clean up the smoke some but more air is key. Not sure about the effects of advancing the timing on a multi fuel engine would be but I'm putting a LDS pump on my LDT along with some pyro and boot. I'm also looking to see if the parts in these two pumps are the same part numbers.. If the timing button is thinner then the one in the LDT then that would be a key element to make more HP.

I do not know if they would run better with a little advancement. They will run real good just getting a pyro and turning the fuel up. I have run the inner nut till it bottomed out turning up the fuel to it's real max. The smoke never cleared and there are less mosquito's around plus the cylinder temps would climb fast.

 

[DavidWymore]

IIRC, advancing timing increases cylinder pressure, and compression is already high. Might stress it excessively.

 

[Theodgeman]

Very true! I have worked on tons of 6bt Cummins engine s and found a factory engine like about 18 degs advanced timing. Cant say much about a Multi Fuel engine as I'm new to working on them and don't know if playing with the timing would do much. I'm talking to a guy that has been build injection pumps for years about the hydraulic heads and hope to find out were they make more power from the HD90100A head to the HD9065A on the LDS engine.

 

[Theodgeman]

So I just got off the phone with the guys at the IP shop and they say the heads are all 9mm plungers and the timing button is there to change timing. they also say that they can make anyone of these pumps flow the same as a LDS IP or more depending on adjustment made to the IP. I need to stop by and talk more about what they change It sounded to me like they adjust the screw on the fuel rack.

 

[rustystud]

So I just got off the phone with the guys at the IP shop and they say the heads are all 9mm plungers and the timing button is there to change timing. they also say that they can make anyone of these pumps flow the same as a LDS IP or more depending on adjustment made to the IP. I need to stop by and talk more about what they change It sounded to me like they adjust the screw on the fuel rack.

Be sure to post your conversation with the shop here. Pictures would be nice too !

 

[JasonS]

So I just got off the phone with the guys at the IP shop and they say the heads are all 9mm plungers and the timing button is there to change timing. they also say that they can make anyone of these pumps flow the same as a LDS IP or more depending on adjustment made to the IP. I need to stop by and talk more about what they change It sounded to me like they adjust the screw on the fuel rack.

The button on the LDS427-2 is a BO901 and all of the rest from LDT to LDS are BO903. Ambac specifies that the BO903 is the replacement for the BO901. The ambac manuals also specify that the replacement buttons must be lapped to the plungers. I have NO doubt that anyone with a couple of wrenches can achieve LDS horsepower on an LDT by simply adjusting the pump on their LDT. i am just curious of the differences in the pumps/ heads.

What is, perhaps, more interesting is that every head shows evidence of contamination causing scoring of the plungers. These came off of running engines so, it appears that the pumps can tolerate a bit of wear before they are not serviceable. However, I believe that the stock fuel filters are the weak link and I wouldn't consider spending the money on a replacement hydraulic head without the spin on fuel filter kit.

 

[gimpyrobb]

Why? Do you think a spin-on filter, filters 10micron better than a cartridge 10mic filter?

 

[gimpyrobb]

More food for thought:

http://www.steelsoldiers.com/showthread.php?53428-Magnetic-fuel-filter&highlight=filter

 

[JasonS]

Why? Do you think a spin-on filter, filters 10micron better than a cartridge 10mic filter?

No, I don't have any issue with the paper element itself. It is the sealing interface (cork) and the o-ring on the shaft that I don't trust to be 10 micron tight.

 

[rustystud]

No, I don't have any issue with the paper element itself. It is the sealing interface (cork) and the o-ring on the shaft that I don't trust to be 10 micron tight.

 

[DavidWymore]

I want to change out at least one filter to much less than 10mic, I have some 2mic.