Does anyone know how to adjust the fuel metering on a Stanadine DB-2 mechanical Injector Pump. This should be the Pump on the 6.2 as well as my '93 6.5.


Edited by: quantum mechanic

I know how to set it. Screw it out for less and screw it in to screw-it-up. Actually you have a DB2 pump unless your running a big Jhon Deere engine in there. The DM was a large rotor heavy duty pump used on commercial type engines. Exactly what do you want to adjust or change in the pump?

unless your running a big Jhon Deere engine in there.

Jhon Deere, LOL
What a tube!http://www.dieselplace.com/forum/smileys/HiHi.gif http://www.dieselplace.com/forum/smileys/HiHi.gif http://www.dieselplace.com/forum/smileys/HiHi.gif

Diesel Pro





GOOZE-BA-BA

GOOZE-BA-BA

Looks like dieselpro has tube steak on his mind

This is the pump. by the green wire is a screw, I think for idle set.


This is a front view.http://www.dieselplace.com/forum/uploads/B9Z_dm-2.jpg


This is a side view .Look at the little spring and there's another screw.


http://www.dieselplace.com/forum/uploads/53C_screw.jpg





Someone out there actually know where the fuel metering screw is on a mechanical injection pump?

I said I could. You see in your last picture the name tag? Right beside it is a small cover with two 1/4" head screws. Remove cover and fuel will drain out. Rotate the engine or have someone bump the engine over till you see a allen screw thru the small hole. Using a good 5/32' allen wrench, screw in to increase fuel and back out to decrease, or in other words screw it in to screw it up. Remove wire to solenoid to prevent cranking while bumping engine. 1/4 turn in will net about a 10 to 15% increase in fuel output with smoke on hard acceleration. Note: This only affects wide open throttle out-put. Idle and light cruise speeds will not be altered.


Green wire is fast idle solenoid with adjusting screw. Screw in picture below spring is Idle screw.


What are you trying to do?

'93 L65 5spd, I have a 3" straight exhaust( no muffler or compound bends) turbo WG welded full open and a supercooling system ( like an intercooler but uses stock a/c system). I thought This truck was something untill I started tweaking my '94 EFI L65 and my dad's '96 L65. and as it happens, it's wide open throttle I am after. This truck makes almost no smoke (except starting) but doesn't accelerate well while towing up hills. I wanted to try fuel metering as a solution before spending any $$ for things like HP injectors.

I would turn it 1/4 turn to start and as much as needed afterwards. The easiest way to find the allen screw in the hole is to pull the cover in the front of the pump to see the drive gear. Rotate the engine so that the dowel pin thru the gear is at the 10 o'clock position. The allen should be in the hole. What you are setting is maximum fuel setting. "fuel metering" is not the normal wording. The pump alone is quite capable of putting out more fuel than the engine can burn so save your injector money.


If you want to bump your Maximum rpms up (High Idle) go to the rear of the pump and just above the Head where the lines go is a screw to set max RPMs. Probably has a plastic tamperproof cap over it. Loosen the jam nut and using an allen wrench screw it in to screw it up. You can gain maybe 200 more rpm, maybe more.


Might try advancing the timing by moving the pump toward the drivers side. Not while running.


More fuel means more air. Put a new K&N filter.


Fuel cetane improver like Stanadyne Jr. helps.

Question for Diesel Dan - Since the adjustment flattens the center of a spring laid across two fulcrum points, raising the outer ends, the pump plungers are afforded more travel at each stroke. Doesn't this adustment effect fuel increase at any throttle angle, idle to full throttle? Which would require less throttle angle for same fuel delivery as prior to adjustment, and result in more delivery at full throttle?


Also question for Quantum Mechanic - The wastegate is held closed by a spring on the mech inj engines, forcing all exhaust gases thru the turbine, allowing boost to develop.


When exhaust pressure against the 1.25" wastegate valve overcomes the spring pressure, the wastegate blows open, wasting some of the exhaust flow, maintaining boost levels, or reducing over-boost.


A wastegate welded open would not allow boost to develop - if yours is actually welded open, as you described it, that would explain low power levels.


Cranking up the pump will be bad for mosquitoes, and worse for exhaust gas temperatures.

Yeah, The wast Gate weld was a boner. It's welded back in the closed position. I need to make a better setup, one that I could work from the cab. I have this mechanical arm that pushes with 12v current. I should rig it to work the WG with a non-linear potentiometer like the EFI. The ECM doesn't seem to be working on this truck either, no check engine light. I probably fried it when I was welding. The scantool tries to connect, but doesn't. This is a 5spd so the ecm controls the cruise and the brakes, and ?, It runs well enough.