OM606 engine wobble - Page 4 - PeachParts Mercedes-Benz Forum

dieselbenz1 · #46 09-04-2018, 02:33 PM

Quote:

Originally Posted by spock505

You misunderstand, it's not about measuring but performing the same visual tasks as you would pop testing - lets see if all six match each other, if one is a bit out of sorts that could be suspect.

Most of pop testing is visual, checking chatter, spray pattern and so on - i know the injectors are good so any variance is pump side.

Thinking about it, this is a lot quicker than pulling all six holders, no priming either - just plug and play.

I have a small pipe bender for the job.

Make certain to take a video and post it should you go ahead with this.

spock505 · #47 09-07-2018, 06:10 PM

Couple of developments to report, firstly sent off pump serial number to listing above for compete match - need to order...perhaps..

As mentioned during summer month run 100% of veg oil which provides better lube and smoother operation, given this decided to add 500ml of alcohol per 60 litre of veg - cheap skate diesel purge idea ?

Without claiming a complete success, each journey is an improvement on the last, something to watch.

spock505 · #48 11-01-2018, 05:19 PM

Weather in upper part of hemisphere is starting to get chilly, earlier altitude sensor adjustments may have been a worked okay on tick-over but proved problematic when starting.

Anyhooo..reversed changes increasing fuel to air ratio (choke) - this device is fitted to compensate for high altitude where air density deceases/increases.

The purpose of my post is to ask whether this mechanism adds a 'dampening' effect similar to the old SU type carburetors?

There's no doubt it makes a difference to injector performance, just not sure exactly how.

spock505 · #49 03-28-2019, 03:45 PM

Few bits and bobs ordered ready for pump overhaul, one thing to point out is this relates to pumps fitted to OM603. 5 and 6's which don't have torqued nozzle holders.

I point this out as there is much misinformation stemming from earlier pumps requiring more detailed calibration, just because someone made a YouTube video don't mean it's correct

spock505 · #50 03-30-2019, 07:16 AM

Hopefully located the source of problem but likely need couple of small parts, return springs and so on -

Anyone point me in the direction of manual for M series Bosch pump, MW is available online for earlier models but not the latter M type.

Thanks,

spock505 · #51 04-08-2019, 04:17 PM

Vac pump gasket due to arrive tomorrow, hopefully crack-on pulling the injection pump for rebuild.

On a related subject, I was amazed at how much influence the ADA had on gear shifts. During adjustment to the lean side shifts went back to hard, opening up (CCW) reverse - this would explain what has happened in the past given how out of sync everything remained at time of purchase.

Some ham fisted mechanic had bent the ADA to one side in order to access a glow plug, this then presumably threw out shift changes prompting mechanic to adjust everything else - I came along adding to the woes by adjusting modulator to compensate, pretty sure everything is back within spec (give or take) including a straightened ADA.

Below diagram show the intricate relationship to other pump components including 'bump stop' which directly effects tick over smoothness (amongst other things).

vwnate1 · #52 04-08-2019, 04:44 PM

# 1 : It's the ALDA .

#2: ? Did you find a manual OnLine or elsewhere for the M series injection pump ? .

# 3 : remember to check the ALDA for air tightness ~ a simple vacuum test will do, once the O-Right between the top and lower square halves begins to weep, everything else goes wonky too .

spock505 · #53 04-08-2019, 04:55 PM

Quote:

Originally Posted by vwnate1

# 1 : It's the ALDA .

#2: ? Did you find a manual OnLine or elsewhere for the M series injection pump ? .

# 3 : remember to check the ALDA for air tightness ~ a simple vacuum test will do, once the O-Right between the top and lower square halves begins to weep, everything else goes wonky too .

Nate, it's a non turbo Euro spec car which are fitted with ADA as opposed to ALDA's, see below description (not sure if this is MB spec or forum post)

Intake manifold or atmospheric pressure compensator (ALDA/ADA)

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 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.

spock505 · #54 04-08-2019, 05:10 PM

Nope, no manual for 'M'pump found but aware of major differences between M and MW so fingers crossed.

Back to the ADA v ALDA operation, in summary they both do the same thing which is to raise fuel to the rack post idle.

The input is different for both with ALDA using manifold pressure to increase, the ADA uses atmosphere with outside vent -

The basis of operation is to reduce emissions on tick-over for ALDA whilst increasing fuel fuel on boost (turbo), ADA on the other hand increases fuel as the air thins, i.e off skiing in the Alps.

vwnate1 · #55 04-08-2019, 05:42 PM

Thanx David ;

I didn't realize you're working on a Greaymarket car .

spock505 · #56 04-08-2019, 06:03 PM

Is it worth taking a few pics of the rebuild or is everyone gripped by the Indiana Jones

.....'Don't enter the delivery valve chamber'

vwnate1 · #57 04-08-2019, 06:40 PM

We ALWAYS want to see / read / learn how to do things.....

spock505 · #58 04-11-2019, 09:34 AM

Part one, getting the bearing bolt out (thanks Scotty for starter motor tip)

spock505 · #59 04-14-2019, 08:20 AM

That was epic, very involved with a few surprises - first off finished crank case seal then moved onto pump.

After removing I noticed there was no O ring for pump to block, ended up making one using PTFE tape as everything closed.

There were a few issues getting to the pump apart not knowing if bolts were LHD or RHD, also torque values - due to the extra time needed did't get a chance to document, if anyone wants to attempt the happy to give a few pointers on what to expect.

The issue with my pump related to the delivery valves themselves, these are the main part responsible for delivering fuel whilst maintaining a seal.

Mine felt worn, however it wasn't until I compared these to the spare set from later 962 engine, just how worn they were, almost sloppy.

Measured as best I could and took a chance to swap out all six.... end result..

..sorted, no wobble but the big difference is power - the engine feels totally different losing that sluggish feel, perhaps 20 - 30% improvement so well worth doing

spock505 · #60 04-16-2019, 12:50 PM

Since the pump was put back had to re-adjust everything else due to power bump, started to spin the tyres flooring it lol

Tried to get a few good pics of the old DV's before biffing, no such luck but you get the idea - these were 'rough' perhaps car had been standing without any fuel, almost look rusty compared to the new set - main concern was how loose the tail felt inside main body, that's what prompted a change risking a non fitment and tear down -

When you think about it the guys mimmick the injectors so it could be argued a change of injectors, change the DV's too ?