Anyone running Mercedes engines?

[abrankod]

Hey, just a quick question to you guys...



Does anyone here run/operate any vehicles or equipment with either the Mercedes Benz MBE900 series engines or the larger MBE4000 series engines? If so, do you like them? Any issues with them? Would you buy again?



I ask because at work we have 6 Thomas Built school buses with the MBE906, and these engines have been nothing but problems since the start. They "feature" constantly cracking injector lines, constantly glitching electrical systems, air compressors that blow out expansion plugs which immediately dump all the oil out of the crankcase and best of all the air compressors feature a spline drive that is threaded in the wrong direction, so that as power is applied to it, it unscrews itself from the engine, causing a loss of compressed air for brakes, powersteering and fan drive (the pump is piggybacked to the compressor. )



So what else have you guys seen of these engines/systems?



-Daniel

 

[BigEasy]

The trucking company that I work for (www.crossettinc.com) has bought nothing but 450hp Benz engines in their Freightliners since they became available. No major or repetitive problems to speak of.

 

[CAROLINA CUMMINS]

I work for a large trucking company (1000+ trucks) and all of the MBE4000 engines we have are junk. At least a couple hundred maybe half or so. After this last bunch gets delivered that they ordered they are going back with the DDC 60 series.



I am a professional diesel mechanic as well as some of my good friends and they have more experience with them than i do and we all agree. MBE=junk



I dunno what the problem is, they are supposed to have run for years overseas but they are giving nothing but problems in our trucks, lots and lots of water leaks; 6 individual heads with only 4 headbolts apiece, no jake, only an exhaust brake which doesnt work that well according to our drivers. Lots of other stuff, like the EGR, but what engine aint EGR giving problems on







Steven

 

[TAbbott]

Hey, just a quick question to you guys...



Does anyone here run/operate any vehicles or equipment with either the Mercedes Benz MBE900 series engines or the larger MBE4000 series engines? If so, do you like them? Any issues with them? Would you buy again?



I ask because at work we have 6 Thomas Built school buses with the MBE906, and these engines have been nothing but problems since the start. They "feature" constantly cracking injector lines, constantly glitching electrical systems, air compressors that blow out expansion plugs which immediately dump all the oil out of the crankcase and best of all the air compressors feature a spline drive that is threaded in the wrong direction, so that as power is applied to it, it unscrews itself from the engine, causing a loss of compressed air for brakes, powersteering and fan drive (the pump is piggybacked to the compressor. )



So what else have you guys seen of these engines/systems?



-Daniel

Freind of mine had one. Had identical fuel line problems you experieinced. Repeatedly, until it ran out of warranty, then got traded off on a Seies 60. No problems since...

 

[CAROLINA CUMMINS]

Yeah, forgot to mention the bad injector lines, we've had tons of those.



Also how about a fuel pump drive gear, bolts onto a smooth shaft; no taper, no keyway or key, no loctite on bolt, no lockwasher ------- no nothing. We've had alot of problems out of them, coming loose, truck not running good, not running at all.



I hate to run these MBE's down like this, but i havent been impressed yet



On a lighter note, they do have a fairly easy valve adj.



Steven

 

[BigEasy]

only an exhaust brake

not anymore... 580hp engine brake

 

[CAROLINA CUMMINS]

I seen that, my mistake. Ours dont have that though, its "optional" Not real sure where they would put it though, they would have to have a severely redesigned intake/ valve cover setup it seems.



Steven

 

[MontyDyer]

Freightliner mechanic here. The most common failures seen on the MB906 engine is the EGR cooler leaking internally. It is a Valeo honecomb cooler that develops cracks in the tubes and eventually lets coolant into the exhaust stream. The 2nd would have to be cracked fuel jumper lines, and the check valve in the head is prone to failure and causing hard starts.



The 2004 906's had a 15mm tstat housing bore that was too small, this caused the engine to overheat at the first start up of the day. A recall was issued and a 30mm bore is now standard.



The 4000 as well, is prone to the jumper tube lines cracking. The main cause of jumper lines cracking or breaking is overtorqueing of the line itself during installation. The 2nd cause is from people loosening off the line to bleed air out of the system. Never crack the line to bleed air, instead use the included compuchek fitting on the filter and a vacumn canister. On the 4000, when a jumper line needs replacing, it is also necessary to replace the transfer tube.



Both engines have experienced problems with frequent 146 codes which corresponds to the EGR temps sensor. The 4000 has even had a few temp sensors break off and go into the intake. There is a service bulletin out on both engines right now to remove the sensor and completly do away with it and install a plug. Reflash the PLD so it will not look for the sensor.



As far as internal failures, I have been on one internal failure, and that was a rod bearing spun on #2. This engine had coolant contamination due to the EGR cooler leaking into the intake for quite awhile.



As for the engine brake on the 4000 and 906, they use a system called a constant throttle valve, it is operated the same as the jacobs brake like we are used to, however it is built into the head and is visible just below the rocker arms. Together, with the engine brake, it makes a very good brake. However one without the other and it doesnt do very good.

 

[CAROLINA CUMMINS]

Interesting, I haven't had alot of experience with the MBE's, but I working on them more and more everyday.



Monty, We do change out the transfer tubes with the line also, lots of those breaking/leaking. We even had one transfer tube with a hole rusted in it; from the inside, i was told. The MBE 4000's we have are a little different from what I am used to working on, but I'm catching on.



Steven

 

[MontyDyer]

Yeah, there a little different, it takes awhile to get to know them.

 

[CAROLINA CUMMINS]

All this week we have a tech from Covington Detroit Diesel to fix alot of recalls on the trucks at our terminal, I believe he's replacing thru tubes and lines on all of them and also exhaust manifold gaskets on some. Could be some more stuff.



Steven

 

[skrohn]

Just purchased 07 freightliner m2 mbe900 automatic, local freight, truck checked out clean, great first 3 months, only 190,000 miles. And so far egr valve and cooler replacement, oil check valve by pass, module, water pump, up to 9000.00 in repairs and half shops cantveven work on them, truck going byby never by mercedes again even if its in with detroit!!! Horrible

 

[94tc2000]

a little off topic and if some one knows a better place to post please let me know any one ever by pas the turbo on the mbe 900 and run em N/A with an intake just on the intake runner of the engine itself ?

 

[The patriot]

The original post is 10 years old.
Dang....

 

[52m37]

I have a 260hp OM906LA in my 05 Unimog U500 camper. EGR cooler failed at ~14k, replaced under warranty with improved part, deleted at 35k. Now motor has 100k, no problems at all, but carry lots of parts due to travel to places like Siberia/Mongolia, Australia etc.
I especially like the 1200 hr oil change interval sans EGR = 40k miles.
Last oil analysis showed only 44ppm Fe and TBN 11.5 after 25k mi.

 

[Timd32]

I have a 260hp OM906LA in my 05 Unimog U500 camper

Had to look those up, never saw one of those.

Here is one that is pretty slick, these folks are out of Moab, UT according to the site I found just off Google.

They are pretty neat rigs.