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Injection pump adjustment
MW-Pump
   

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.
Throttle stop- Prevents the external linkage from forcing the internal linkage past set point. *Do not touch but make sure your external linkage is contacting the stop at WOT. **This adjustment will NOT increase your maximum power and can possibly cause internal linkage binding.
High Idle- Limits maximum engine RPM. *This can effect the governing of idle RPM and idle quality. **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.
Idle Regulation Bumper Spring- Adds idle unloading spring force against the flyweights. *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.
Start Quantity Cutout- Allows full fuel for start but not run. *Also affects other internal functions. Do not touch.
Torque Control Capsule- Reduces rack travel with increased RPM. *Reduces smoke at higher RPMs due to the engines lower volumetric efficiency at higher RPMs. 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 1/4 turn each time. ***Caution: Adjusting the capsule too much can result in the engine becoming slow to return to idle or not returning to idle at all.

M-Pump
   

The procedure should be the same for all OM602/3, pre-1996 OM604/5/6 and European OM616/7 engines, but the throttle linkage setups will vary between models. Thanks to Tom (tomnik) for helping put this together.
   
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)
           
The one on the right above is the 87 om603 pump

1: Remove anything blocking access of the rear of the pump. On the 86/87 603, this means pulling the windshield washer reservoir, all throttle linkages, the bowden cable and the cruise control actuator. The oil filter housing does not need to be removed on the OM60x or OM61x engines and the intake manifold can remain in place on OM60x engines.

2: Remove the ELR (round red device at the top-rear of the IP). The Torx screws may be tight due to the factory locking compound on the threads. This does not apply to OM617 engines.
   

3: Unscrew the rear governor plate (6 screws). Early pumps have flat head screws, late pumps have Torx screws. When you pry of the plate, a fair amount of engine oil will spill out. Have rags handy to catch the mess.

[attachment=4892]
4: Now you should have full access to the governor of the pump. To increase the full-load fuel quantity, loosen the jam nut, and turn screw 2f (bottom left) out (CCW). Make careful note of the position of the slot, before & after adjustment. Try 1.5 turns total for the first adjustment, or go in half-turn increments if you don't want to max it out. For the OM617, this will bring power near that of the stock MW-Pump. 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 (idling auxiliary spring) will restore the idle speeds to normal.

5: Whatever number of turns you made to full-load screw 2f, make the IDENTICAL adjustment to the idle stop screw, 2b (top/right). If you turn 2f out 1.5 turns CCW, then also turn 2b out 1.5 turns CCW. This decreases the idle setting but it also moves the external throttle lever. After the idle adjustment, make sure the lever is not touching the pump body. If screw 2b 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. NOTE: Make sure your new settings do not change when you tighten the jam nuts on both 2f and 2b. Make sure the nuts are snug, but don't over-tighten them... if you break something, you could end up pulling the pump to repair or replace.

6: If possible, use a new gasket for the rear cover, and a new O-ring for the ELR. They are available from Mercedes dealers at a reasonable price. Clean and dry the sealing surfaces, re-install the cover and ELR.

7: Because you turned screw 2b, which moved the external throttle lever towards the rear of the engine, you now must adjust all three throttle linkages. Lubricate the ball/socket joints with ATF or wheel bearing 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.

8: Re-connect the transmission Bowden cable. Slacken to lower shift RPM, tighten to raise. Make sure the cable travel is not limiting linkage movement, you may need to bend the bracket slightly.

9: Press the pedal to the floor and inspect the lever at the back side of the pump, it should go through the entire range of motion from the idle stop to the WOT stop. You can have a helper sit in the car or use a heavy object placed on the pedal. Be sure to remove it before starting the engine!

10: Reassemble all the items you removed to gain access to the pump. OM60x: Leave the ELR wire off and start the engine. The idle should be ~500rpm. Re-connect the ELR wires and the idle should jump to ~650rpm if you have the trim plug set to #4. OM61x: Use the external adjustment screw 3 to fine-tune the idle speed. CW decreases idle, CCW increases idle.

11: Test drive! With the engine fully warmed to 80*c during the daytime (not night), watch for black smoke. You will probably notice smoke when you mash the pedal from a stop. OM60x: If smoke is visible until boost builds, lean out the ALDA setting by adjusting the screw CW 1/4 turn at a time or removing the shim, installing a thinner shim until the smoke is not clearly visible once the vehicle starts moving. OM61x: These engines do not have an ALDA on the M-Pump. You will have to live with some smoke, adapt your driving habits to prevent it (with good throttle manipulation) or fabricate an ALDA using a 5-8psi wastegate actuator attached to the STOP lever. No smoke should be visible at WOT, after the turbo has spooled up, if you have the boost set at 14psi.

12: Watch your exhaust temperatures! 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, 1500*F (815*C) for very short intervals (under 5 seconds). Most of the increased fuel feed from either of these pumps can be noticed between 2000 and 4000 rpm's, after that the high idle (maximum RPM) setting automatically starts to reduce fuel. Boost pressures above 14psi should not be needed although YMMV as to the exact boost PSI needed. Maximum RPM Loosen the 29(?)mm lock nut of 2m and turn the 10mm Allen screw CW. One half turn = 150rpm. Torque Capsule Loosen the 22mm lock nut of 2e 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).

Hey guys, my first post on this awesome new board!!

I did this mod too. I ended up losing the rack limiter way down in the bowels of the governor and had to pull the IP (no pen magnet). I would very much recommend just pulling the IP to do this mod. Its so much easier that way, and you will probably drop it, so just save yourself a little aggravation to start.

The results are astounding- much more power than just turning the full load nut. On the butt-dyno, the car really throws me back in my seat now, even with 2.47 rear gears. I would highly recommend this adjustment to anyone with a good running engine, a pyrometer, and an adequately-sized intercooler.

MTUPower Wrote:Could you go into detail about the pulling of the IP and the re-install? Future members will want to know how to do this, and whether or not you used a lock pin to keep the IP in the correct timing.

Okay, pulling the IP is about one of the most painful things one can do on a Benz, besides trying to get the rear IP cover off without removing the oil filter housing.

To pull the IP: There is the easy way, and the hard way. I will go step-by-step through the easy way, then step-by-step through the hard way.

THE EASY WAY:

0) Set engine to TDC on the crank balancer
1) Order a filter housing gasket, and an IP gasket
2) Remove the filter housing
2a) Cut the short side of the appropriate allen wrench (possibly 6 meters, but I'm not sure) with a grinding disk, making sure to take small cuts at a time to keep it from heating up and losing its hardness. You will have to cut enough off, but not too much. To gauge how much enough is, find the hardest-to-reach allen bolt holding the filter housing to the block (the ones that go through the filter housing). It should be the one closest to the "frame" rail. Make sure you have about 1/2-3/4inch clearance between the top of the wrench and the "frame" rail.
2b)Detach the oil cooler lines
2c)Detach the oil pressure sender line, and the oil line off the rear of the filter housing (turbo oil line)
2d)Pull all the bolts holding the oil filter housing to the block. This will require some creativity with extensions, sockets, allen wrenches, etc.
2e)Lift the filter housing out
3)Remove The IP
3aa) detach all the fuel lines, injector lines, oil lines, vac lines, linkages, etc from IP
3a)Remove the rear mounting bolt from the IP, and the rear mounting bracket from the block
3b)remove the 3 nuts on the IP flange
3c)gently pull the ip back out of its hole, and lift up.

THE HARD WAY:
1) Order a new IP gasket, or don't if you are feeling lucky (please just do it, this is not a time to trust ones feelings)
2) Set engine to TDC
3) By some wonderous miracle, remove the rear cover from the IP (I have done it about 5 times now, trust me it gets easier each time)
3a) you will need some sort of fancy screwdriver with a ratchet to get at the flathead screws. Take a look before you jump in and acquire the appropriate tools
3b) you will need to remove the shutoff solenoid and the rack damper bolt before you can get anything out.
3c) once (if) you get the IP cover off, now you can remove the rear mounting bolt for the IP
4) remove the bracket from the block
5) remove the bolts from the IP flange, remove the IP as per the easy way, but its harder due to the filter housing.

Re-installing the IP:

1)Put the IP back in (with the new gasket)
2) loosely attach the 3 flange bolts
3) check, double check, and triple check your timing with the drip tool, and set your timing. If you can't get it, it means you are off a tooth or 2 on the splined collar, and you have to pull the IP out of the splined collar, rotate it either towards or away from the block (towards = advance, away = retard) nearly its entire range of motion, and stick it back in the collar. Keep rotating and checking until you get the timing right.
4)re-attatch all the parts in their correct locations.

A NOTE: Get a shop manual. It explains all this in much better detail than I am able, and it has pictures

ANOTHER NOTE: The easy way is MUCH EASIER, even though it seems more complex. Just do it the easy way, it will take less time and you will be happier afterwards.

LAST NOTE: The hard way can be made easier in the future if you replace the IP cover screws with some allen-head screws while the IP is out.

This is a miserable job to do on these cars, but if you want more fuel, you have to get used to it Also, keep a supply of oil filter housing gaskets onhand because you will likely want to mess with the torque control, which although it may be possible with the oil filter housing on the car, it is much easier and quicker to just remove the housing.

ONE LAST THING, AND ITS IMPORTANT:

AFTER RE-INSTALLING THE IP, MAKE SURE YOU FILL IT WITH THE CORRECT AMOUNT OF OIL THROUGH THE FILL PLUG!! FIND A PICTURE IN THE FACTORY SHOP MANUAL OF WHERE THE FILL PLUG IS, AND HOW MUCH OIL TO FILL IT WITH. This can be accomplished much easier with a large syringe (I used a 35cc one) with a piece of flexible hose stuck on the end.

I propose that this thread be dedicated to the topic of getting the MW IP to pump more fuel, or to do it in a more optimal manner (full fuel earlier, later, etc)

As it stands right now, as I understand it, there is the rack limiter removal, the TC adjustment, and the max rpm (high idle) adjustment.

I understand there are other parts, settings, and configurations in the IP that can be "played" with.. Since fitting an MW IP with larger elements is some ways off yet (although on the mercedesshop forum there has been recent activity in this direction), perhaps getting the most from a pump with stock elements should be the current focus of development. My goal here is just to spark off a discussion to this effect.

Good move on the thread merge Forced.

Along the lines of making the pump return to idle:

I know governor springs are available for P-Pumps (Cummins) that are used to increase max-rpm... but aren't we more after the spring that pulls the rack back? (The little one on the outside that goes between the fuel lever and the rear IP mount?) I haven't looked at a schematic of the IP in a while (BTW- Does anyone have one to post here? It would be a good place for it), but as I recall, the IP has a fairly weak internal spring, and the stronger of the two is external... Maybe the IP has no internal spring at all? I honestly don't remember :roll: . In any case, would this be fighting the governor at idle? Is there a different spring in the governor that controls the fixed-speed-governing of the engine below 1000rpm? Having this information would make figuring all this out exponentially easier... Maybe its time to take apart my extra (dead) IP and play a bit :ugeek:

Well I pulled the rack limiter today. No discernable improvement in the lowend. Upper end is imroved but only slightly, certainy goes to 4400 a heck of alot quicker. ~3hrs including a trip to the car store for the magnetic pen. Get one before you start down this path. I considered adjusting the torque control as well but figured one thing at a time. If your oil filter gasket is new you can probably reuse it but have a new one ready.


[edit] A few hours later and Im pretty happy. Anything over 3k is improved. I am running bio right now and its pulling like it was straight diesel.

One thing to note, you can change the filter gasket if it ever starts leaking without removing the housing or disconnecting any lines from it. Just pull the allen bolts and slide the gasket in. Saves much time and aggravation.

Glad to hear the rack limiter removal was successful, I'm surprised you aren't seeing very much in terms of low-end gains... are your linkages adjusted :lol: ? I am at about the same level of tune as you and loving it so far.. I found nearly the opposite effect, I have much more power below 3000rpm, and not much more above 3000... In fact, mine starts to cut out above about 3700. Next time I have the rear cover off will be for maxing out the TC and turning the high idle limiter up so it revs to 5300 or so, combined with an exhaust cut-out in the downpipe. It won't be driven there too much, just it would be good to be getting full fuel all the way up to 5000.. It seems like that will be about the pinnacle of what is possible with 5.5mm elements... except for injector nozzle machining... unless anyone has more ideas?

One other question, are you running an ALDA?

GREASY_BEAST Wrote:One other question, are you running an ALDA?

Yes I am, maxed all the way out. You? It is entirely possible that the alda is preventing the low end from getting any more fuel. I also (very probably) have low compression on 2 of 5 cyl.

GREASY_BEAST Wrote:Next time I have the rear cover off will be for maxing out the TC

Don't get too adjusting happy with the TC or you'll end up with a runaway engine. 1/8-1/4 turn at a time seems to be the max adjusting increment to be sure the engine will return to idle.

I am running no ALDA. I think you may find a performance increase if you remove it possibly?

Forced- I won't get too crazy with the TC. I have a couple filter housing gaskets and I plan to go up in 1/8 turn increments until it starts to run away, then back down in 1/8 turn increments (hopefully just one) until it runs okay again. I also will be playing with the max idle. I think this will net huge gains in the 3000-5000rpm range.

P.S. Just checked the gearing calculator, 5000rpm with my 2.47 rear is 150mph!! That will never happen, because the power to overcome air resistance just isn't there, but I'd be plenty happy with a cruise speed of 130... Just need that power high up in the rev range..

GREASY_BEAST Wrote:I am running no ALDA. I think you may find a performance increase if you remove it possibly?

Forced- I won't get too crazy with the TC. I have a couple filter housing gaskets and I plan to go up in 1/8 turn increments until it starts to run away, then back down in 1/8 turn increments (hopefully just one) until it runs okay again. I also will be playing with the max idle. I think this will net huge gains in the 3000-5000rpm range.

P.S. Just checked the gearing calculator, 5000rpm with my 2.47 rear is 150mph!! That will never happen, because the power to overcome air resistance just isn't there, but I'd be plenty happy with a cruise speed of 130... Just need that power high up in the rev range..

Put the pipe down son!

MTUPower has done the torque adjustments I believe he might provide some input. I need to find a NA IP I can yank the cover plate off of to run no ALDA. I will point out that he or whomever it was, was using the ALDA to bring it back to idle after heavy torque adjustments.

So I got to take the car into the mountains this weekend for the first time since the mod and was using reg diesel as well. This car behaves more like a gasser now than ever before. Love it.

Nice! How's your acceleration above 3krpm? Mine falls off in a fairly round (perhaps parabolic) fashion in the 3000-3200 range, and totally dies in the 4100-4300 range, but 2000-2900 really scoots (well, at least compared to what it used to do...)

Are you guys monitoring fuel pressure at the inlet of the injection pump at all?
Dropoffs in power like that can be indicative of fuel pressure, fuel flow and/or aeration issues.

Beers,

Matt

RE: fuel, no but thats a good idea.

I dont have a power drop off till 4700rpm where it should. I'll pay a little closer attention.

Yes I am measuring fuel pressure at inlet, and it stays around 10psi. I also have an electric fuel pump feeding the stock lift pump, so I'm sure the IP is getting adequate fuel.

Are you sure you don't have any power dropoff all the way up to 4700? I seriously doubt that based on how the TC and max rpm governor function...

10psi @ idle or WOT?
What is the specified fuel pressure for an M or MW inline pump?
I know the P inline pumps like around 30psi at idle and ~35psi off idle/under load...

Beers,

Matt

10psi at idle, a little more.. maybe 12 with RPM. The return fuel line off the IP is connected with a banjo bolt that has a spring with ball in it. This is what sets the pressure. I would venture a guess that over time this spring degrades and the pressure drops... maybe its time to install a restricting orifice of some sort to try to make more pressure..

BTW- You can't get to the spring, so it's neither adjustable nor upgradeable.

The Bosch P series inline pumps have a similar banjo bolt/valve that we call the 'overflow valve'.

The older ones were not able to be cleanly disassembled/reassembled...but the newer ones are. You can take the spring/ball right out of it and stretch the spring if it has become lazy. Perhaps a P7100 valve could be retrofitted to a Merc M/MW pump...any idea on the dimensions on the Mercs?

Here's a link that has a good picture of a P7100 overflow valve of the newer modifiable (is that a word?) type. You can buy these pretty cheap on eBay or through other outlets. TST Products is a great company...but they don't deal in parts like this in enough volume to be able to sell them at low prices like some other shops could.

Beers,

Matt

Looks just like it... I wouldn't be surprised if it was the same dimensions... I don't recall the dimensions specifically off the top of my head right now but I think it might be about 10 or 12mm dia.

GREASY_BEAST Wrote:Yes I am measuring fuel pressure at inlet, and it stays around 10psi. I also have an electric fuel pump feeding the stock lift pump, so I'm sure the IP is getting adequate fuel.

Are you sure you don't have any power dropoff all the way up to 4700? I seriously doubt that based on how the TC and max rpm governor function...

Drop off? No. Flattening? Of course.

P series is DI or IDI? 2bar sounds like alot, but perhaps increased pressure is needed.

Okay, power flattening correlates fairly directly with acceleration dropoff (at low speeds... below about 55mph). In my original post I was referring to my acceleration curve, not my power curve, because the butt dyno only measures acceleration.

That would be pretty neat if you could use a P-pump overflow valve on your M/MW's. 10mm sounds about right, IIRC.

I've never seen a P-pump on an IDI...but my experience with them is limited to the Cummins B and C-series engines...both of which are DI.

I have an A-series inline pump on my Deutz tractor - that's also DI and a VERY sweet running little 4-banger.

Beers,

Matt

I wonder if more pressure in the fuel gallery would get us any results? Its certainly worth a try..

With OEM pumps, there's a fine line to walk between too little pressure and too much. You could probably get by with upwards of 30psi at the inlet with an M/MW - but the OEM lift pump bolted to the IP and driven from the IP's camshaft probably isn't up to the task.

P-pumps that have had some work done to them like nearly 50psi at idle...

Beers,

Matt

I took apart one of those OEM lift pumps and modeled it using a CAD program for one of my classes last semester. I would be willing to bet a lift pump that the internals can take 50psi or greater. However, the part that actually does the pumping is a spring. The roller rides on a lobe on the IP camshaft, which compresses a spring, which pumps the fuel. I would suspect you would need a stronger spring in the lift pump, thereby making more pressure. And more force on the IP camshaft, which is the big question. I'm not willing to bet an IP

this may be a stupid question, but could tweaking the external rack stop result in any fueling gains?

No. It only prevents binding of the internal linkages.

I think I adjusted mine a few turns before I knew any better, but have not noticed any binding. I guess I will just leave it where it is now.

The rack limiter removal took me 3 hours with the pump and oil filter housing in place on the engine, including changing the DV's back to stock. One good trick is to use a long screwdriver (about 12") on the two inner screws, I was able to get my hand behind the oil filter housing to turn the screwdriver. The hardest screw was the lower left, too close to the filter body to get a screwdriver in there and partially blocked by the oil cooler lines. Having the injection lines out of the way also made things easier. In other words, YES, it is possible with the pump and filter housing in place and bear claw hands.

Results? I must say that I'm thoroughly disappointed. I can get some good smoke by revving from idle without a load but I can't discern any difference at all in acceleration.

Its not even remotely close to the kind of power I had with the cut DV's. Too bad the idle was crap and the EGTs were insane.

The only real benefits I notice after all that work are a smoother idle (readjusting the rack damper) and a quick shutoff (replaced the old leaking shutoff actuator with a new one).

Here is a quick smoke video.
http://www.youtube.com/watch?v=KcV3uQSBpXQ

Shame, it was night and day for me. Odd that it didnt have the same effect for you. Its most noticeable in the upper RPMs. I think you were just spoiled after the DV's

I don't think its that. Acceleration is about the same as before, around 13 seconds.

I thought I would add a quick comment about R&R of the mw pump. While I was making many small changes in succession and I had the pump in and out a lot. I got it down to under 30 mins from shutdown on the bench and back on and running again. The key was removing the lower support bracket from the block and the pump. With this out of the way all you have to do is set your timing or insert the pin, remove the three mounting nuts and the fuel lines and linkage, grasp the pump by the ALDA and lift up and back. Once you have zeroed in on a setting it is a good idea to reinstall the bracket. The return spring can be a bitch. I hope this helps and encourages more of you guys to go after these adjustments in a incremental fashion.

Bob

Oh yeah this is done with everything else still in place oil filter, shutdown and all.

Had to order some new oil cooler lines, new engines are seeping badly at this point. Looks like I'll be doing the rack limiter removal again as well as adjusting the torque control.

I removed the rack limiter, that was fairly easy. The torque control however was a complete fucking fuck up. I may have to get a new IP at this point. I made the socket for the lock ring and got it open. Made a 1/4 turn on the inner nut and then proceeded to lock it, found that the inner nut had turned, have no clue how far. I am going to modify the existing instructions to recommend using a small screw driver to lock it back down. As I am waiting for oil cooler lines I am unable to test the current setup. Teh sucks. I did start the engine for half a second and return to idle seemed ok. No run away. No clue if I have botched it or not.

Removing the rack limiter didn't make much of a difference for me. The change is there, just not a dramatic as I was lead to believe it would be.

I'll try to get a fuel pressure gauge installed and adjust the fuel PSI regulator's spring as cervan did on his 240D.

ForcedInduction Wrote:Removing the rack limiter didn't make much of a difference for me. The change is there, just not a dramatic as I was lead to believe it would be.

I'll try to get a fuel pressure gauge installed and adjust the fuel PSI regulator's spring as cervan did on his 240D.

Rack limiter is an upper RPM improvement. From your dynos it looks like your choking about 3500 which might be why you didn't see that much improvement. The Torque Control issue is really worrying me. At this point it is just hope and pray.

Now is the 3500rpm choke due to TC or high idle cutout? I still think high idle needs adjustment

Well Well.

Much ado about nothing. Got her all bolted backup, adjusted the spring on the block side of the IP and took her for a spin. I live on a big hill and by the time I got to the top, all I could do is let a WAAAHHHOOOOOO out. 0-60 is faster, no timing but I am able to get to 60 in less distance than I used to. Much less. I would like to adjust the torque more but am pretty happy right now.

Oh man. Took the car to the mountains this weekend, next oil change I am dickering with the TC again. Had a lot of fun keeping up with the liter sport bikes in the turns.

thats some awesome info on the full load limiter removal. does anyone have any more info on the TC adjustment? like which way to turn which parts for a performance increase, how much is a general rule of thumb when starting from stock? also which way to turn the fast idle to gain more fuel at the higher rpm. im not looking for an rpm increase, just some more power in the higher rpm range. thanks

ken

TC Adjustment, 1/16 turn increments. Be aware that the inner nut will turn with the lock nut. Make sure you have your fuel line unclamped, if you go to high on the adjustment the IP will NOT return to idle.

Just did an informal dyno with the rack limiter removed. I'll update the dyno thread.

I updated the first post to include the M-Pump full load adjustment.

If anyone has adjusted the torque capsule on the M-Pump, please let me know your procedure/results and I'll note it in this guide.

I recently came across this STT document outlining adjustment of the M-Pump for their OM616/7 turbo kits.


  STT_M-Pump_gov_mods.pdf (Size: 95.55 KB / Downloads: 1295)

This translation is by tomnik, thank you Tom.
The whole thing is related to tuning on a bench. Rod travel is the rack arm that directly turns the injection pump plungers, visible under the side cover plate.
-------------------
Setting of the injection pump
Max. quantities

Pre-condition: pump rev 1000/min, (Regulierhebel= regulating lever=) external linkage lever at full load position. (Regelstangenhub= (internal) rod travel, the thing that turns the plungers) RH to be set to 15,5 mm by turning adjusting screw (25).
This is bench adjustment, where the ip is driven at 1000 rev/min and the rod ravel is set to a certain value (= fuel quantity)
After that the rod travel is increased to 17,5 mm by adjusting screw (17).
Do the same at 1600/min and 2180/min.
(This is not clear for me, does this mean check the rod travel at 1600 and 2180/min for added 2 mm?)

ADVISE: The values given in the (STT) service information for rod travel and quantities are only approximates and will allow variation in the range of several 1/10 mm.


High idle

External linkage lever at full load, pump rev at 2550/min.
Adjust the rod travel to 10,5 mm by turning the (23) (spring seat).
Control quantity approx. 26 ccm.


Low idle

Turn adjustment screw (50) 2 turns ccw.
Turn (28) ccw until a gap occurs towards the inner low idle stop of the external linkage lever.
After that proceed as follows:
1) Close the gap (eliminate the play) by carefully turning the screw cw.
2) Turn the screw (still 28) cw another 1/6 turn
At 350/min adjust the rod travel to 6,5 mm by turning screw (29). The quantity should be 7,0 ccm.
Then increase the rev to 370/min (what will result in a different rod position) and increase the rod travel by 0,1 – 0,2 mm by turning (50).

Post-check of low idle adjustment

At 820/min and external linkage lever at idle stop the rod travel must not exceed 2,5 mm.


On the right side of the page:

Regelverlauf(= curve rod travel over rev)

Check rod travel at the indicated 4 revs (external linkage lever at full load stop)


Important

Minor variation could be tolerated at 2300 or 2400/min. Any variation at 2500/min has to be corrected by adjusting (23) (pre-tension of the spring).
At 2950/min the rod travel must be in between 0 and 0,3 mm.

Update.

I expanded M-Pump description picture for more detail and added information about adjusting maximum RPM.

Adjustments so far on my OM617 (These will not work well on the OM60x):

Idle, Fine- 1/4 CCW
Idle, Coarse- 2-3/4 CCW
Full Load- 2-1/2 CCW
Max RPM- 1/4 CW
Torque Control- 1 CW

Great power, no idle quality or return to idle issues at all. 12psi boost is a little too low, EGTs get past 1250*f after more than 20seconds WOT.

Why not just remove the rack limiter?

There isn't one in the M-Pump.

I'm curious if any body know anything about the old mechanically governed pumps off the 60s-70s 220d? in this article they turned up the fuel a lot on one? I'm curious if one of these pumps would work on my 1980 240d turbo? or If I could get more fuel that with the stock pump??? and how to turn up the old pumps?