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Old 12-17-2010, 05:53 AM
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Lightbulb Injection Pump fuel adjustment for the MW and M pumps, engine tuning and maintenance

Factory service manuals can be purchased online directly from Mercedes:
StarTek W123 online service manual
Mercedes-Benz Classic Center technical literature

All information presented herein is purely for informational purposes only, I and MercedesForum assume no liability for your or anyone else's actions. All procedures and adjustments in this guide are to be performed AT YOUR OWN RISK. The pump can only be properly calibrated by a Diesel injection specialist on an injection pump test bench, this is not intended as a DIY at home pump calibration guide. Getting your engine into good running condition and installing an exhaust temperature gauge (pyrometer) is STRONGLY recommended before you contemplate touching any injection pump internals. If you believe any of the following information to be incorrect please make a post or contact me through the forum PM system and it will be corrected asap.

Pyrometer, aka EGT gauge
If you skip installing a pyrometer you risk major damage to the engine and turbo from high combustion heat.
Extended WOT of more than 10-20 seconds can create combustion temperatures high enough to damage the engine. This damage is not instant, its cumulative. The longer you run hot the more damage excessive temperatures will do and it won't be obvious there is a problem until its too late. 1250*F (675*C) is a safe limit for continuous output, 1400*F (815*C) is acceptable for short intervals (under 5 seconds).

A gauge, amp, harness and probe can be purchased for around $250 from many sources, eGauges for example. ISSPRO is one of the best and they make a color-coded gauge for easy interpretation on the move. VDO makes a good gauge as well, but its backlighting is poor.

There are two methods of installing a pyrometer pre-turbo, bottom and top.
Post-turbo installation is not recommended for any vehicle. Too many variables can drastically affect the measured temperature. There is no way to determine a safe temperature under different driving conditions and with different vehicle configurations.
The probe cannot be installed in the EGR port, the probe will not see any exhaust flow.

This method requires removal of the air filter assembly, CCV oil drain tube, EGR, turbo, exhaust manifold and intake manifold. It cannot be done with any of them on the engine. You will need a new manifold gasket (shared between the two manifolds), turbo flange gasket, turbo oil supply gasket, oil drain tube o-ring, CCV oil drain tube o-ring and EGR gasket.

For the steps on removing the manifold assemblies I suggest buying a factory service manual: StarTek W123 online service manual

Drill and tap the exhaust manifold for 1/4NPT and install as shown.

This method risks damage to your turbo and is not recommended!

Remove the air filter box.
Start the engine.
Have an assistant revv the engine to 2000rpm while you drill the manifold as shown.
Keep the engine revved. Coat the 1/4NPT tap with thick grease and cut the threads.

Boost pressure, air filter and exhaust
First off, more is not always better!

The maximum useful boost pressure is determined by four factors:
1: How much fuel you're injecting (Exhaust gas temperature)
2: If you cool or supplement the charge air; Intercooler, water injection, nitrous, etc
3: Altitude
4: Pre-turbo exhaust pressure

A pre-turbo exhaust manifold pressure (EMP) gauge is very recommended to help determine the ideal boost pressure. The "no visible exhaust smoke" method works, but its like trying to assemble a jigsaw puzzle without the box picture.
An EMP gauge can be built by installing a brass ferrule fitting in the manifold before the turbo and using 2' of 1/16" copper tube (to cool the exhaust) with a standard boost gauge. The EMP gauge should read 2x that of your boost gauge for adequate measuring range.

When boost pressure is excessive, drive pressure will be higher than 2:1 to boost pressure. This is caused by a lack of fuel to spin the turbo fast enough. Drive pressure higher than 2:1 has two major effects, it drastically increases exhaust temperature and increases engine pumping losses. Both increase stress on the engine and reduce horsepower.

The perfect ratio is 1:1 but 1.5:1 is also very good. You have found your ideal boost pressure when your turbo is working in this range and there is no visible black smoke from the exhaust.

Some examples of boost pressures I recommend for the OM617 series. These are not guesses. They are based both on airflow calculations and real-world trial and error.
Stock engine: 11psi
Stock engine with an intercooler: 8psi
Rack limiter removed without an intercooler: 15psi
Rack limiter removed with an intercooler: 13psi
Note: These boost pressures are at sea-level (14.7psi-absolute). If you live above 4000ft elevation you will need more boost to make up for the lower atmospheric pressure (For example, Denver's barometric pressure is 12.1psi).
Here is an airflow calculator to help you determine the boost you need (its already programmed for a factory-stock OM617a): Not2Fast: Turbo Calculator

Altering the air filter and exhaust systems do not provide any benefits in power or economy.
The stock intake is already a true cold air intake and the filter flows efficiently to 400cfm.
The stock mufflers are a straight-through, unbaffled, design and the diameter is already large even compared to modern cars.

Installing an aftermarket "cold" air intake, installing a larger diameter exhaust and/or removing the mufflers will produce a 0hp change in power. The only change they will produce is noise.

Timing chain
Valve cover nuts: 15Nm
Camshaft bolt: 80Nm
Chain tensioner cap: 90Nm

Camshaft timing is an important factor in both engine performance and efficiency. Late timing will prevent the engine from fully charging and evacuating the cylinders of air and exhaust, causing poor performance, high EGTs and smoke.
The chain and sprocket should be inspected during every valve adjustment service.

On both OM61x and OM60x engines, remove the valve cover and rotate the crankshaft clockwise (ONLY) until the mark on the camshaft bushing lines up with the static mark on the camshaft tower.

Once aligned, check the marking on the crankshaft dampener. A pin identifies #1 TDC, the arrow on the engine block identifies true #1 TDC. The difference is your chain elongation/wear.
A normal chain will measure 2-4* ATDC, a worn chain 5-8* and a very worn chain 10*. At 11* the chain, tensioner rail and tensioner should be replaced.
If your chain is 18* or more ATDC or before TDC, there is a major problem that must be corrected.

Inspect the camshaft teeth for wear. If they have a sharp or jagged end you need to replace the camshaft sprocket, injection pump timing device and crankshaft sprocket as well as the timing chain.

Offset keys are available to correct minor wear and tolerance differences up to 10* of crankshaft angle.
Offset keys are sold in camshaft angle. Therefore a 3* key will correct for 6* of chain elongation as measured at the crankshaft.
Valve timing should never be corrected where timing would be advanced of crankshaft TDC!

The chain tensioner must be removed prior to camshaft sprocket removal, failure to remove the tensioner may damage the guide rail.
The thermostat housing must be removed to access and remove the tensioner.
First remove the spring and then the tensioner itself.

After tensioner removal, the camshaft sprocket may be slid forward to the point just before complete removal from the camshaft to exchange the woodruff key.

Valve clearance
Valvecover nuts: 15Nm
Adjustment and lock nuts: 14mm
Adjustment must be performed at a maximum interval of 14,000 miles. I suggest an interval of 10,000 miles.

Valve adjustment is required maintenance of all OM61x engines.
Ignoring the adjustment interval will cause hard starting, rough idle, black smoke, high fuel consumption and high coolant temperatures.
If ignored for a significant length of time, valve face heat damage and excessive camshaft lobe wear will occur.

OM615/OM616/OM617 (non-turbo) Valve clearance at 20*c or below coolant temperature
Intake: 0.10mm (0.004"), 0.015mm for lasting ambient temperatures below -20*C
Exhaust: 0.30mm (0.012")

OM617a (turbo) Valve clearance at 20*c or below coolant temperature
Intake: 0.10mm (0.004"), 0.015mm for lasting ambient temperatures below -20*C
Exhaust: 0.35mm (0.014")

OM601/602/603/604/605/606 engines have automatic hydraulic valve lash adjusters and do not have any possible clearance adjustment.

Do not adjust the valves if the engine temperature is above 20*c or within 15 minutes of operating the engine.
Use a deep 27mm socket and ratchet to rotate the engine. Do not use the starter to "bump" the engine or the power steering pulley to rotate the engine (If you could, the belt would be WAY too tight!)
Place the feeler gauge between the camshaft lobe and tappet pad when the lobe is pointing up and to the oil rail as shown below.

Lubricate your feeler gauge with oil prior to use.
Correct adjustment is achieved when your feeler gauge has stiff drag required to slide it between the cam lobe and tappet.
The next gauge size up should not be able to fit between the gap and the next size lower should have very little drag.
Replace the valve cover gasket after every use.

Print this layout to assist you in keeping track of the valves that have been adjusted.

With the #1 cylinder's exhaust valve in the correct adjustment position; From front to back (1 through 10), the valves are adjusted in the following order.
1, 6, 4, 2, 8, 3, 9, 7, 5, 10

Injection timing
Torque specs
Delivery valve holders: 45Nm
Injection lines: 25Nm

Pump rotation
Towards the block: Advance
Away from the block: Retard

Correct injection timing is critical to good engine performance, fuel economy and EGTs.
Too early (advanced) and your engine will rattle like a bucket of nails while putting huge stress on the headgasket from the pistons working against combustion pressure!
Too late (retarded) and your engine will smoke white/gray, stumble when cold and have very high EGTs at full load.

Stock timing is 24* BTDC. This is great for the stock engine, but anyone increasing fuel quantity on the stock injection pump will see high EGTs at full load from the long injection duration.
26* BTDC is great for those maxing out the stock injection pump. A tired engine may intermittently misfire when cold after the glowplugs cut off but this will not cause any harm.
28* BTDC is the furthest that timing can be safely advanced without significant risk of headgasket damage.

Advancing the timing beyond stock gives the fuel a longer time to burn and allows for the longer injection duration naturally associated with increasing fuel injection quantity. That puts more power into the crankshaft and less heat into the exhaust.

1: Set your engine to the desired base timing using a 27mm deep socket on the crankshaft nose. DO NOT use the power steering pump pulley to turn the engine! You must verify that the piston is in the correct cycle (compression and not exhaust) by removing the oil fill cap and inspecting the first two valve lobes to see if they are both pointing up and away from the engine. If they are pointing down you must turn the engine one complete revolution to get the correct cycle.

2: Remove the #1 injection line (17mm).
3: Remove the #1 delivery valve holder (15mm MW or 32 spline M)

4: Remove the delivery valve plunger and spring (#3 and 4)

5: Reinstall the pipe connector (#1) and snug it in place
6: Install the drip pipe tool. (Note: The "bubble method" is an unacceptable and inaccurate substitute) A tool can be home-made using a spare injection line and cutting it in a similar fashion as the tool.

7: Tie down the throttle lever wide open
8: Loosen the 3 front and one rear mounting bolts
9: Pump the priming plunger and rotate the pump in the necessary direction until the flow from the pipe equals 1 drip per second.
Some effort will be required to move the pump with the injection lines attached. The injection lines may be removed if you wish but they will have to be slightly bent to reattach.

10: Lock down the four mounting bolts, remove the throttle tie-down, remove the test pipe, install the delivery valve/spring and install the injection pipe. The engine will misfire for 30 seconds as air bleeds from the lines.

Intake manifold or atmospheric pressure compensator (ALDA/ADA)

MW left, M right.

The intake manifold pressure compensator (ALDA device) is comprised of a housing (103) with barometer unit (103b). The absolute pressure acts upon the barometer units through a port (103a) to the charge air pipe of the engine. Accordingly, the barometer units react to each pressure change with a change of length.
All movements are transmitted to the compound lever of the governor and to the control rod.
As the absolute pressure drops, the barometer units expand. The correction linkage (1030) of the units is pressed downwards and acts on the compound lever to move the control rod in the direction of "reduced quantity”.
As the absolute pressure rises, caused by a higher air and/or charge pressure, the movement is performed in the opposite direction- i.e. in the direction of "increased quantity".
When the control lever is in the idle position, the effect is approximately zero.
It is purely an emissions device to prevent/minimize the emission of black smoke, removing the ALDA will not increase maximum power.

The intake air under atmospheric pressure is further compressed by the turbocharger.
Atmospheric and charge pressure together produce the absolute pressure prevailing in the charge air pipe of the engine.

nl Speed at the start of charge operation
a Atmospheric pressure, corresponding to suction quantity
b Charge pressure
c Absolute pressure, corresponding to charge quantity
n Engine speed
p Pressure in bar

The atmospheric pressure compensator (ADA) functions in exactly the same manner, the only differences being not connected to the intake manifold (its vent tube must be open to the atmosphere) and a slightly more sensitive operating range.
Removal of the ALDA/ADA is not recommended. Unlike other emissions controls, this device is beneficial in that it significantly reduces emissions without harm to the engine's power, economy or longevity and it reduces carbon deposits inside the engine.
Black smoke is not cool.

Fuel rack travel sensor

MW left (64), M right (L7)

The control rod travel sensor is installed in the governor of the injection pump. It consists of an iron core, two coils (measured value and fixed value coil) and two short-circuit rings. It is connected to the electronic control unit by a 3-pin plug.
The coils (b) and (d) are attached to the iron core (a) which is fixed in the housing. The short-circuit ring (e) is connected to the control rod (2t) and is displaced with the control rod without touching on the bottom leg of the iron core. The fixed value coil (b) and the short-circuit ring (c) are attached to the top leg.

The fixed value coil (b) with the short-circuit ring (c) represents a constant inductance. Depending on the change in position of the control rod (2t), the distance between the short-circuit ring (e) and measuring coil (d) changes. The variable inductance produced is then compared to the constant inductance. From this the electronic unit determines the control rod travel.

This is purely an emissions control device to aid the ECU (Electronic control unit) in determining the correct amount of EGR gasses to flow to the intake manifold. If you have defeated EGR operation it serves no purpose and has no effect on engine performance.
This device is only present on 1984 California and all 1985-1994 models.

Last edited by ForcedInduction; 07-06-2017 at 12:31 PM.
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Old 05-02-2011, 08:42 PM
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Injection pump adjustment
NOTE: After adjustment, refill the pump with fresh oil (about 1/2 quart). On the MW, the fill port is a plug on the top left side of the governor housing (The ALDA points its direction in the picture below). On the M, remove the shutoff actuator.


No idle compensation is required unless noted.

External Idle Screw- Controls the fine idle speed.
*Set the engine between 700-800rpm.

ALDA- Limits fuel at low boost pressure to control black smoke.
*Loosen the 10mm locknut and adjust the screw CCW in 1/4 turn increments to increase low boost fuel until you see black smoke when the accelerator is floored from a standstill.
**This adjustment will NOT increase your maximum horsepower. It is purely an emissions control device.

Throttle stop- Prevents the external linkage from forcing the internal linkage past set point.
*Make sure your external linkage is contacting the stop at WOT when pressing on the accelerator pedal. A cracked rubber bushing on the firewall can cause failure to contact.
**Loosen the 14mm lock nut and turn the 9mm screw until two threads of the screw are visible.
***This adjustment will NOT increase your maximum power without first increasing the internal full load setting.

High Idle- Limits maximum engine RPM.
*This can effect the governing of idle RPM and idle quality if adjusted beyond 1 turn.
**Loosen the 10mm lock nut with a wrench while holding the screw stationary (Do not use a socket to loosen the lock nut, the screw will turn with the nut!)
***1 turn equals approx. 250rpm, CW increases.
****This should only be adjusted if your engine is in top-notch condition. Increasing maximum RPM comes with a serious risk of throwing a connecting rod and/or floating the valves resulting in catastrophic engine damage.

Full Load- Sets the maximum rack travel while the engine is running.
*19mm and 9mm locknuts must be loosened and the 13mm nut turned CW to increase maximum fuel quantity.
**The rack limiter lever can be completely removed from the pump for maximum power. See below for this procedure.
***Anyone that tells you NOT to remove the limiter is inexperienced. Removing the rack limiter is the ONLY way to get maximum power from your engine. Leaving the limiter in place, by definition, will LIMIT your maximum power.

Idle Regulation Bumper Spring- Adds idle unloading spring force against the flyweights to prevent loping/hunting.
*Should not be adjusted.

Coarse Idle RPM Screw- Sets the idle speed in combination with the outer fine adjustment.
*Should not be adjusted except in conjunction with torque control capsule adjustment.
10mm lock nut.

Start Quantity Cutout- Allows full fuel for start but not run.
*Also affects other internal functions. Do not touch.

Torque Control Capsule- (Do not adjust) Reduces rack travel with increased RPM.
*Reduces smoke at higher RPMs due to the engine's decreased volumetric efficiency at higher RPMs. It is not used to increase power.
*Loosen 21mm lock ring and turn 14mm capsule CW to increase. Back out the coarse idle RPM screw by the same amount as you turned the capsule.
**A pyrometer is an absolute must if you are going to adjust this. Take it easy and only go 1/8 turn each time.
***Caution: Adjusting the capsule is strongly not recommended. It will result in the engine becoming slow to return to idle and causes excessive heat (EGTs) at high RPMs.

Full Load Limiter Removal Procedure
An exhaust temperature gauge (pyrometer) is necessary for reliable long-term operation of the engine after this modification. Do not exceed 1250°F in continuous operation or 1400°F in short bursts (under 5 seconds). Do not use any kind of sealer on any of the gaskets.

Anyone that tells you NOT to remove the limiter is inexperienced. Removing the rack limiter is the ONLY way to get maximum power from your engine. Leaving the limiter in place, by definition, will LIMIT your maximum power by LIMITING how far the fuel rack can move towards maximum fuel. Adjusting the torque control primarily, as suggested by inexperienced people, will cause excessive heat (EGTs) at high RPMs. Adjusting or removing the limiter increases fueling across the entire RPM range, the torque control will still function exactly the same.

1: Remove the oil-filter housing. This is optional, with a long screwdriver its very possible to adjust everything with the housing in place.
2: Remove the pump back plate including shut off actuator and rack damper.
3: Disconnect the vacuum device linkage and tubes. Remove the top lid screws, turn the top lid (or remove both the ALDA and top plate for best access).
4: Remove the limiter's screws and nuts.

5: Push the limiter from the adjusting screw into the inside of the pump.
6: The hardest part is "digging" the limiter out of the bottom of the pump. A small (1/4" or less) pen magnet is strongly suggested for this step. It can only exit through the thin slot on the top of the pump. You have two options- You can turn (rotate) the parts around inside the pump or you can punch out the guide pin the limiter used to slide on. The pin is no longer needed.

7: Once the limiter is out replace everything back in reverse order minus the limiter. Remember to use a new oil filter housing gasket and get the filter housing and block mating surfaces surgically clean. Be careful not to drop any gasket leftovers into an oil channel. If you get an oscillating idle this is a good place to replace the Rack Damper bolt with upgrade unit (upgraded one is gold anodized, the old silver in color) in the back plate of IP.

Note: No governor adjustments are necessary. The rack limiter only affects the maximum available throttle/fuel when the engine is running, it has no effect on any other governor functions.

When you are done, you should have 5 or 6 parts left over (depending on the removal method you chose). DO NOT DISCARD THESE PARTS in case you decide to revert the operation at a later date.

8: Advance the injection timing to 26* BTDC to compensate for the increased injection duration. (Listed near top of the article)
9: Increase boost pressure to the suggested level to provide the necessary air to burn the additional fuel. (Listed near top of the article)
Failure to follow steps 8 and 9 will result in high EGTs and possible engine damage!


The procedure should be the same for all OM601/2/3, pre-1996 OM604/5/6 and European OM616/7 engines, but the throttle linkage setups will vary between models.

17: Torque Control Capsule- Reduces rack travel with increased RPM.
23, 24: High Idle- Limits maximum engine RPM.
25: Full Load- Sets the maximum rack travel while the engine is running.
28: Coarse Idle RPM Screw- Sets the idle speed in combination with the outer fine adjustment.
29: External Idle Screw- Controls the fine idle speed.
50: Related to low idle adjustment (28)

Left- OM61x european models
Middle- OM60x non-turbo models
Right- OM60x turbo models

ELR (Electronic Load Regulation)
The lift rod (163) rests against the guide lever (2a). The actuator (Y22) is supplied by the electronic idle speed control unit with a clocked D.C. voltage in the frequency range of approx. 50 Hz. If engine speed drops (e.g. drive position engaged or power steering turned to full lock), the actuator is energized with a higher voltage.
This causes the lift rod (163) to press against the guide lever (2a) and the control rod (2t) to move in the direction "a" increased quantity.
As soon as the engine speed increases, the voltage is reduced and the control rod (2t) moves in the direction of “b” reduced quantity.
With the ELR unplugged, idle speed should be reduced to 500rpm. Idle speed is adjustable in 50rpm increments via 8-position switch (location varies by model)

Full load quantity (2f/25)
*To increase the full-load fuel quantity, loosen the jam nut, and turn screw 2f/25 (bottom left) out (CCW). Make careful note of the position of the slot, before & after adjustment.
**NOTE: Poor idle quality (1000rpm+ unloaded, 500rpm in gear) is known above 1.75 turns for the OM60x and above 5 turns on the OM61x. 2 turns CCW of the nut 2k/50 (idling auxiliary spring) will restore the idle speeds to normal.
***Whatever number of turns you made to full-load screw (2f/25), make the IDENTICAL adjustment to the idle stop screw, 2b/28 (top/right). If you turn 2f/25 out 1.5 turns CCW, then also turn 2b/28 out 1.5 turns CCW.
****If screw 2b/28 is backed out too much, it can touch the intermediate plate behind the ELR. Check the spec per the FSM procedure if you must change any shims for clearance.

*Because you turned screw 2b/28, which moved the external throttle lever towards the rear of the engine and rotating lever towards the valve cover, you now must adjust all throttle linkages. Lubricate the ball/socket joints with ATF or #2 multi purpose (red) grease before re-attaching them.
**Due to the number of vehicle models this guide crosses, linkage adjustment is not detailed in this post. Use the procedure in the factory service manuals to adjust your throttle linkages, just remember that the rod lengths specified in the FSM no longer apply after you internally adjust the injection pump.

Internal coarse idle adjustment (2b/28)
*CW increases idle, CCW decreases.

External fine idle adjustment (3/29)
*CW decreases idle, CCW increases.
**If you run out of adjustment range, you must adjust the internal coarse idle screw to change the affected range.

Maximum RPM (2m/23)
*Loosen the lock nut of 2m/23 and turn the 10mm Allen screw CW.
**One turn equals approx. 250rpm.

Torque Control Capsule (2e/17)
*For best drivability results, Do Not Adjust
**Loosen the 22mm lock nut of 2e/17 and turn the 12mm 2-prong capsule CW.
***This adjustment will raise the RPM when the governor starts to pull back fuel (due to the engine's reduced volumetric efficiency).
****Adjustment is not recommended for the first time modifications. It will cause a slow return to idle (no deceleration fuel cutoff) and excessive EGTs above 3000rpm.

Pneumatic M-Pump
Yes, many diesels do have a throttle!

The procedure should be the same for all OM615 and pre-1976 OM616 engines; 200D, 220D and pre-1976 240D models.

The engine must not be started before the throttle and air pipe are installed and the injection pump diaphragm is checked for leaks. Failure to observe this caution can result in severe engine damage from overspeeding (run away).

OIL: This type of injection pump does not have a connection to the engine's oil system. The pump's oil should be changed at the same time as the engine's oil using the same type and viscosity of oil. The red cap is the fill location and the drain plug is located at the lower rear of the back.
Remove the plug midway up the side of the pump, fill the oil until it starts to come out this hole. It will take approximately 1/2 quart.
Synthetic oil will not harm this pump or the engine.

A good seal of the vacuum pipe and manifold is extremely important. Any cracks or leaks in the hose, banjo bolts, throttle gasket, throttle shaft bushings, intake manifold or diaphragm in the injection pump have a significant effect on the operation of the engine.
If a turbocharger is to be added, the throttle MUST be relocated to the inlet side of the turbo. Having the throttle after the turbo can cause the engine to accelerate out of control (run away), not decelerate when the throttle is closed and/or be extremely sensitive to throttle movement.

Control, AKA, "Gorilla ****"

Stopstellung (S) - Stop
Fahrstellung (F) - Run
Vorglühsteuerung (V) - Glow plugs
Anlaßstellung (A) - Start


There are only two adjustments on this pump. There is no direct maximum RPM, high RPM fuel reduction or altitude compensation on this pump. These functions are controlled by the venturi in the throttle body.

Maximum Fuel (N): Adjust CCW to increase fuel. Adjust only 1/4 turn at most without an external source of air (turbo, supercharger, nitrous), excessive adjustment will cause high exhaust temperatures and engine damage during extended high throttle use.

Idle Stabilizer (Q): Do not adjust unless the idle speed is unstable (hunting up and down in RPM) NOTE: Any air leaks in the control system will make idle adjustment impossible.


Idle Speed (U): Adjust CW to increase idle speed.

Maximum RPM (T): Adjust CCW to increase maximum RPM. NOTE: Like the mechanical governor pumps, increasing this setting does increase high-RPM power by delaying when fuel begins to be cut off, but it comes with significant risk of major engine damage from overspeeding.

keywords: STD superturbo superturbodiesel turbodiesel w123 w126 w116 300D 300CD 300SD 300TD OM616 OM617 OM602 OM603 OM605 OM606 CDI IP injection MW-pump M-Pump power diesel

Last edited by ForcedInduction; 07-06-2017 at 12:39 PM.
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Old 05-09-2011, 08:35 PM
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My 300D was retrofitted M-Pump from a non-turbo European 300D in place of the stock MW pump. As of June 2013 I have reinstalled an MW pump.

The following is for reference only. An OM60x engine will require different adjustments.
Total adjustments for my M-Pump as of 2011/05/10.
Full Load- 6 CCW
Idle, Coarse- 6-1/4 CCW
Max RPM- 3/4 CW
Torque Control- Zero
Idle stabilizer- 2 CCW

Dyno'd at 147.5hp at the wheels with W/M injection.

My 240D's OM617 has the stock MW-Pump.
Total adjustments for my MW-Pump as of 2011/05/10.
Rack limiter removed.
ALDA removed.

Last edited by ForcedInduction; 06-02-2013 at 03:03 PM.
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Old 02-19-2012, 11:44 AM
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So I'm trying to locate the ALDA and I can't find it. Can you give me a hand and describe it for me please. Thank you
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Old 02-21-2012, 02:52 PM
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I know where the ALDA. I just can't find the 10mm locknut that you are talking about.
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Old 03-18-2012, 08:22 PM
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Added a section on setting the correct boost pressure.
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Old 04-03-2012, 12:33 PM
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Hi, this is some awesome info! I have a couple questions about the egt gauge install and the rack limiter removal. Why do you want to run the engine at 2000rpm while drilling and tapping the exhaust manifold, is it to keep the metal hot so its easier to work with or maybe to blow the shavings out so they don't go through the turbo? Also when you remove the Alda to get the top cover off do you have to put it back a certain way or does it not matter? You mentioned filling the pump with oil, does the pump get engine oil circulated through it or does it use its own oil? Lastly does removing the rack limiter cause more fuel all the time or does it just allow for more enrichment according to boost?

Also I don't technically have a Merc lol here's my vehicle, its an 86 Toyota Pickup 4x4, its been done and driving for almost a year I just don't have any other pics on this computer

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Old 04-03-2012, 12:52 PM
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Originally Posted by inlinesicks View Post
Why do you want to run the engine at 2000rpm while drilling and tapping the exhaust manifold
The exhaust pressure will blow out any metal shavings.

Also when you remove the Alda to get the top cover off do you have to put it back a certain way or does it not matter?
It doesn't matter.

You mentioned filling the pump with oil, does the pump get engine oil circulated through it or does it use its own oil?
It gets engine oil, but removing the back cover drains its sump.

Lastly does removing the rack limiter cause more fuel all the time or does it just allow for more enrichment according to boost?
It only allows more fuel at maximum throttle.
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Old 04-03-2012, 02:29 PM
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Awesome, what happens when you remove the ALDA does it just dump the maximum amount of fuel when you hit the gas?
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Old 04-03-2012, 06:00 PM
ForcedInduction's Avatar
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Location: Federal Heights, Colorado
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The ALDA is an emissions control device and overload protection. If you remove it the engine can be damaged if the wastegate hose fails.
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