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Mercedes om606 engine


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14 minutes ago, matfield said:

I'm almost finished the conversion with fully electronic 606 and merc 5speed auto, and it would turn a standard r380 to playdough in minutes at full throttle. Gazfab has a lot of great products, and takes a lot of the hardship out of the conversion, but the 722.6 merc box is worlds ahead of the zf.

 

a lot of the merc guys fitting sprinter flywheels mill down the lip on the flywheel when using the c270cdi 6 speed manual box in merc conversions, might be a better option than taking it off the bellhousing

Not with you on milling the flywheel? It would be nice to move the input shaft a couple of mm closer to the end of the crank to get the last couple of mm of spline engagement, I would need to add material on to the flywheel to achieve that.

I ground off 3mm of the "cup" lip on the end of the crank to allow the sprinter flywheel to sit against the crank face, could that be what those guys were referring to?

to be honest, I've generally found I'm better off doing my own thing as everybody has a different opinion! I didn't want an auto but everybody kept saying the r380 wouldn't fit or that I needed an om603 flywheel and spacer etc. I considered merc manual boxes but the 220 and 270 CDi manual boxes are rated for slightly less torque than the r380, yet "everybody" on the net who usually haven't tried both, reckon the r380 is cheese and the merc boxes are fine. My experience is that the merc boxes are ok but still not that tough and much more work to fit when you take the divorced transfer into account or the coupler to the ml gearbox. Merc themselves derated the om605 to preserve the 270cdi manual box!

 

an upgraded r380 should handle 500nm 

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2 minutes ago, Orgasmic Farmer said:

Surely hp is irrelevant. It is the torques that matter here. My Massey Ferguson engine is only 80 HP but I don't reckon an R380 would last 2 minutes on the back of it :-)

Yep very true! R380 is rated for 380nm of torque. I'd guess your massey is possibly a 4.236 Perkins non turbo if it's 80 hp and not too new maybe (guess possibly more likely a phaser these days perhaps)? The 4.236 non turbo are rated at 250 to 275nm torque I think, so the r380 would surprisingly be ok! The om606 is rated at 330nm in standard form, again ok in the r380 and surprisingly more than the Perkins 4.236

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Good guess and correct on all counts. I guess if geared for road speeds and on road tyres it probably would be OK. Stick it in crawler gears on tractor tyres on grass and stick 10 tonnes on the back and try a few hill starts :-) 

Maybe it would be OK. But I suspect something would give pretty quickly

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You might be right! Got to remember there's a hell of a lot of reduction gearing on a tractor though. The later parts of the transmission (i.e. Near the wheels) are subject to massive amounts of torque due to the gearing. The engine and primary gearbox a lot less so

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11 hours ago, Orgasmic Farmer said:

Good guess and correct on all counts. I guess if geared for road speeds and on road tyres it probably would be OK. Stick it in crawler gears on tractor tyres on grass and stick 10 tonnes on the back and try a few hill starts :-) 

Maybe it would be OK. But I suspect something would give pretty quickly

Another point is that your Perkins makes its peak torque at around 1400 rpm, and at that speed the individual torque "pulses" as each cylinder fires will be quite substantial, giving the gearbox a hard time with shock loading. It's that that would break it rather than the actual output numbers

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Yep, but I'd rather wait until it's up and running in case something isn't right! Don't want to cause folks a load of problems. Hasten to add I have no business interest in it either, I'm keeping Gaz fab posted on what's happening as he doesn't really have the time to look into it but already has some of the bits

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At this stage it's all conjecture anyway.

My own experiences  have led me to believe that it's more a case of how a vehicle is treated (driven), than how much power you're funneling through the transmission.

I've seen the 5 speed 717.404 take a massive pounding of supercharged m117 5.6L v8 and not even whince, and in the same sentence, seen an identical box totally minced internally from a 2.3 litre 16v N/A engine. 

I've seen 722.6's reworked and taking brutal shock loads from Hemi Chrysler SRT's and twin turbo OM606's with 8mm pumps. I've seen the same transmission fail behind a standard m113 5.5L kompressor v8 in an E55 AMG.

Whether the r380 handles the torque is probably not the entire question. The boxes can be made to be 'reliable'. Problem is, 380Nm is not a lot when we're talking about an OM606. The saving grace however, is that the torque peak moves up the rpm band thanks to the OM606's turbo. 

However, I feel that removing the dual-mass flywheel will do more harm than good.

Despite all the conjecture and bull**** that people carry on with, the Dual-Mass flywheel has many advantages over a single mass unit. Reduced intertia at the bite-point of the clutch (on take up and on shift point disengagement) and an incredible reduction in drivetrain shock loading. This is why nearly every manual vehicle on the planet now uses them.

I'm not saying they are 'better' but they certainly do have a lot of advantages in this application. One of the other advantages is the increased mass.  Sure, 17.5Kg is a fair amount of mass, and coupled with the centrifugal force of the crank, it does have a tendency to slow the rpm increase a little. But, again, this is an advantage offroad, where low-rpm stability is required for difficult low-speed low-traction low-gear scenarios.

A dual-mass flywheel vehicle is a much smoother and more tractable vehicle to drive.  I have a dual-mass 6 speed manual behind my m104 (which is exactly the same block as the OM606) and can state for the record that it is far superior to the single mass flywheel in smoothness.  But it does hamper the engines ability to spin up rapidly. I also have a brutally lightened single mass flywheel and will also state for the record, that it transmits every single power pulse through the input shaft gear and has killed input shaft bearings, reverse idler gears and other nonsense in my supposedly 'unbreakable' dogleg 5 speed getrag. So believe who you will - I choose to bank on experience. It;s like these people who say " you need a racing clutch" when the standard 240mm sachs clutch and pressure plate lasts over 100,000km with constant abuse - on a 200kW engine.  

So time will tell how long it will be before that sprinter dual-mass-delete flywheel helps to destroy your input shaft gear and bearing.

It's exactly these scenarios where an automatic has a distinct advantage, not only from a torque multiplication factor, but also from a tractive stability and smoothness.

There have been quite a few 'manual versus automatic'  debates/arguments recently. The sad reality is that in modern scenarios, a transmission like the 722.6 which has a controllable shift program, the ability to lock into a single gear and the distinct advantage of being a fluid-coupled drivetrain, gives it a significant advantage.

The only downside is the difficulty of bump-strating it. Something a manual box can easily do. It's also something that in a vast desolate environment (like most of Australia) there is a singular purpose and necessity to have a manual transmission in preference to an automatic. Or a good mate who can tow you when the **** hits the fan.

I hope for your sake, the r380 can handle the increased harshness at idle rpm's from the single mass flywheel conversion, but in the same sentence I also suspect it will not long be for this earth purely because of this engine characteristic - and not because of the claims of 'massive torque'  others have stated.  The damage is not done when in constant mesh. the damage is done when the mesh is NOT constant. 

Please keep us informed of your progress. I hope it works out for you.

 

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I certainly won't disagree on the dual mass subject (my business is building vehicles and re-engineering them) and on a 4 cylinder engine they make a massive difference. Less so on a 6 cylinder.

using the dual mass delete wasn't intended solely to delete the dual mass, it was primarily because I don't have any flywheel either single or dual mass as the om606 was never available in the uk in a manual form to my knowledge. Most people seem to adapt the om603 single mass. I chose to use the sprinter version. 

 

more a case use of availability than idealised design!

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  • 1 month later...

Looks quite close to the firewall...

Can you take a pic from the side so I can see how far back it's mounted? maybe a pic of the engine mount as well?

quite interested in the progress, It's looking good - keep us posted!!!

cheers!

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Cheers, will try and post some more, that was a test and I forgot I had left it up!. All my pictures are on my Facebook and I can't post them properly on here with them hosted there unless I'm missing something. They are also taken with a carp phone so not great! Should finish the bodyshell metalwork tomorrow then it's shell off to blast and zinc spray, rebuild chassis etc. 

In terms of firewall clearance, it's not too bad. I expected to need to remote the oil filter, then found I could get it out ok, but then raised the engine a further 10mm to maximise axle clearance and now I can't! I think a small alteration to the firewall above it will allow it to come out. If not I will go back to making a takeoff plate and remoting it.

Edited by retropower
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I would go for the remote setup.

One of the annoying things about m104/OM606 is the element type filter housing and the cap. Late ones have GR-ABS plastic ****house cap, the early ones have alloy, but they are different sizes! something worth noting when you have to buy a special hazet oil filter socket for each type to remove the caps. PITA. Not MB's finest hour I must say.

Hopefully you also have a housing with the remote cooler. Be aware of the oil filter housings that use the coolant heat-exchanger. These are notorious for failing in poorly maintained engines, the exchanger core rots out internally and you end up with grey soup for oil and coolant, and big problems. It's common on m104's and OM605/6's.

58c3a737bf0b6_ScreenShot2017-03-11at18_28_27.JPG.7461d9ba3cccf3dbc9035d2fdcef8ac8.JPG

58c3a73a4fcf8_ScreenShot2017-03-11at18_28_01.JPG.9f1edcf7e2207f7da3259a234b7b950b.JPG

58c3a73ccf2c6_ScreenShot2017-03-11at18_27_50.JPG.d5356da1d3a8653faee7fbcb7b978647.JPG

 

603's had an alloy cap with 2 different size nuts/bolt, similar to old om617's 2-bolt cap.

 

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  • 1 month later...

Just so you know, this R380 / LT230 sat behind an OM605 for 12 months. The output shaft (mainshaft) was replaced at time fo rebuild.

Light duty offroad, and on a trip up a shaly hillside the LT input gear gave out spectacularly, sending driver on an interesting and rapid reverse trajectory before the handbrake was effective enough to stop the vehicle.. trailered home, stripped down etc...  and the below pic shows wear on spline from R380. Can't show you the LT, because it's input gear and bearings are now grey paste internally. Yes, lubed correctly etc. perfectly serviceable blah blah blah... I know the owners driving habits and his maintenance schedules pretty rigorous.  I can't upload the input shaft pic, because it's too large, but the shaft itself is fine, the clutch pivot sleeve however, shows a ridiculously abnormal wear pattern on the inside, which doesn't match any wear marks on the input shaft itself. This is somewhat puzzling, as it can only mean deflection on the pivot fork and throwout bearing - possibly the diaphragm is too heavy, but it's a standard sachs pressure plate... I have it sitting on my workshop floor attached to the flywheel.

All I can put this down to, is a weakness in the design - the R380 / LT230 mating splines are less than satisfactory, from a materials perspective (genuine LR) so perhaps Dave Ashcroft has something up his sleeve for you, god knows how long it would have been before the R380's shaft stripped splines and in a way this is a blessing in disguise. Autobox is now going in.... NB there is oil (and fretting corrosion which I removed partially to illustrate the chewed out spline) getting to the shaft, and it was a crossdrilled gear. 

I'll try to show the pinion shaft image. it's truly odd.

 

_JFB1347.jpg

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True CW, this is a pic I found elsewhere: 

Screen-Shot-2015-10-29-at-08.46.45.png

Was the input gear a cross-drilled short spline version of some sort?

Looking at that, there's probably 50% more spline engagement with the second picture (from a TD5), you can just see the wear near the root of the spline.

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On 25/04/2017 at 2:37 AM, mercguy said:

Apparently I'm only allowed to upload 1.95mb, so I cannot upload any more pics. Sorry.

Oops - thought I'd changed all that but I clearly didn't go back and set the rest of the groups correctly :blush:

You should now be able to upload up to 10MB per post (total of all images). If you upload large images they'll be automatically resized to a sensible maximum for web use.

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This is the pinion shaft  - notice no shaft wear, but the inside of the throwout bearing sleeve / pivot fork arm is completely rooted.

I have a feeling this box has been rebuilt more than once, and this wear may be from a previously failed pinion shaft bearing or a failed spigot bush in another flywheel.

Dodgy as all buggery this is, so I can tell you the R380's getting a teardown as well as the LT230.

btw CW, this R380 came form a '92 2 door rossignol disco1 v8. perhaps this is why the output shaft differs to your TD5??

 

 

_JFB1337.jpg

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