Rehabbing a cheap 05 E320 CDI, mini documentary series

[Actros617]

So I've able to save a one owner 2005 E320 CDI with 203k miles for a meer steal ($1500). The Original owner bought this brand new, and was handed down the family until their last kid ran into problems as of now.



The car maintenance history is unclear but it had a recent service sticker of 01/19 almost 6k miles ago at a local Indi Mercedes service center, and the car at time of inspection was running absolutely rough the engine will shake violently and knock during acceleration 1500 rpm I could not drive any faster than 45 mph. up opening the hood as suspected the infamous black death (leaking injector) and a burned up Injector wire harness that causing all that problem.



The problem occurs when a combination of heat cycles, high pressure high heat environment and a flimsy bolt that will stretch with high heat and pressure causes the injector to back out ever so slightly of its thin dime sized crush washer causing the combustion to escape through the weakest point, which is to atmosphere. Neglect long enough and you'll have these build up black hard coal like substance that will heat up enough to melt anything and everything that it comes to contact with that is plastic or rubber.


Overall the car is in ok shape, body has big scuff on the rear bumper and a small dent and deep scratches on of the rear wheel arch nothing too big to worry about. Engine mounts are completely shot, at idle its vibrating everything in the cabin its like having a bass box at full volume its that bad.The good news is transmission shift smooth, there's no suspension knocks, the car tracks straight and it brakes well (despite having the infamous SBC brakes) and the interior is mostly intact and function aside been dirty and neglected of much need cleaning.




So far i've only clean the black death off the injector system and temporary retaped and cleaned the exposed wires of all the carbon , a screw driver, compressed pressure air and shop vac and I've excavated the injectors. It took me a good 1 and 1/2 hours and tons of elbow grease to remove that hardened gunk, and i was rewarded with a functioning Injector 1, engine revs and accelerates without any miss and vibrations.



I've ordered several parts and special tools and they're on their way, in the meantime i've got some research and thinking to do.

[cmac2012]

Has there ever been an upgrade for that flimsy, heat sensitive bolt you mention?

[Actros617]

Originally Posted by cmac2012

Has there ever been an upgrade for that flimsy, heat sensitive bolt you mention?

Unfortunately no, for its application it requires steel torque to yield stretch bolt to keep the injectors in place. Using other harden bolts will result strpping the aluminum threads on the head.

Other diesel manufacturer (BMW/AUDI/VW) uses a same approach but uses way larger bolts almost 2x the size of the original (M10-M12 bolts) that is even longer in thread length, other methods examples the older common rail BMW M57 diesel's uses a bracket with 2 nuts per injector to keep them down.

The Om651 I4 bi-turbo diesel uses a the same clamp style in the OM648 but with larger and longer bolt and new upper sealing surface. However the current OM642 V6 that is in the current 2019 sprinters use still uses the flimsy thin bolt design.

[engatwork]

Good catch.

[ROLLGUY]

be sure to look at the "Black Death" threads here. '05 CDI injector "Black Death" adventure
My first CDI was as bad or worse than yours. My niece still has my first CDI and loves it. No re-occurrence of BD.....Rich

[ROLLGUY]

Also, be sure to have some replacement return line fittings on hand, because you WILL break one or more of them while working on the injectors. I found a vendor on the auction site that had metal ones. Much better than the factory plastic fittings. The return hose is the same as used in all the earlier Diesel engines. No need to buy the factory hose assembly.

[jay_bob]

Here's a youtube guy who is an ex MB dealer tech who deals with this issue on the 648

https://www.youtube.com/watch?v=zEp4GjcXy3o

[ROLLGUY]

Originally Posted by jay_bob

Here's a youtube guy who is an ex MB dealer tech who deals with this issue on the 648

https://www.youtube.com/watch?v=zEp4GjcXy3o

Yes- Alex has the best CDI content on Youtube, and maybe even the best MB content overall. A lot to learn on his channel. Also, lots of performance upgrades for the 211 chassis and the 648 are covered on his channel. A must subscribe for any and all MB owners.

[Actros617]

Originally Posted by ROLLGUY

be sure to look at the "Black Death" threads here. '05 CDI injector "Black Death" adventure
My first CDI was as bad or worse than yours. My niece still has my first CDI and loves it. No re-occurrence of BD.....Rich

Also, be sure to have some replacement return line fittings on hand, because you WILL break one or more of them while working on the injectors. I found a vendor on the auction site that had metal ones. Much better than the factory plastic fittings. The return hose is the same as used in all the earlier Diesel engines. No need to buy the factory hose assembly.

Yes- Alex has the best CDI content on Youtube, and maybe even the best MB content overall. A lot to learn on his channel. Also, lots of performance upgrades for the 211 chassis and the 648 are covered on his channel. A must subscribe for any and all MB owners.

Originally Posted by jay_bob

Here's a youtube guy who is an ex MB dealer tech who deals with this issue on the 648

https://www.youtube.com/watch?v=zEp4GjcXy3o

Indeed Alex is really good guide on how to tackle this problem though i dislike his Clickbait style vids. ROLLGUY thx for the heads up on the return lines snapping off i bought a few on Ebay, I saw some metal ones from another seller thought it would be the best future proof it incase if injector leaks again.

https://www.ebay.com/itm/5X-Diesel-Injector-Fuel-Return-Line-overflow-hose-connector-Mercedes-Dodge-5Cyl-/283275905879?_trksid=p2349526.m4383.l4275.c10#viTabs_0

At this time i'm waiting on lots of parts (thermostat, injector bolt kit, air filters, oil filters, ect) and tools to arrive hopefully by next week i can get started working again.

[Actros617]

Wow talk about a fight these injectors are way the heck stuck in there took me from almost 4 days to remove them.

Tip: If you have the black death, no slide hammer will pull these injectors out, in fact you'll most likely hurt your hands because you're gonna need some serious force to pull these injector which the slide hammer won't provide, we need some serious tons of leverage! Also i presoak these injectors with Seafoam deep creep overnight and warmed this engine up operating temp before pulling the injectors.

Here's a the original idea for effective injector puller
https://www.youtube.com/watch?v=5tcAHBhSx8o&t=1197s

Like in the video, I used 6x 1/2 to 3/8 socket, 6 inch long impact extension, to 6x E10 sockets and place it onto the valve cover bolts, i used some clips to hold the extensions straight and used the air box to keep the right side extensions straight,



Next i used a 10in Wide, 16in Long, and 3/4 in thick steel plate with 3x 3/4in hole drilled into the plate and place it on top of the 6 socket, 2x 4 Ton bottle jacks, with a 2in wide, 16in long by 1in thick hollow steel structural bar, mercedes injector puller, a slide hammer that attaches to it. I also place ramps on the passenger side of the vehicle both front and rear wheel to straighten out the engine so the heavy plate and whatever is stacked on it wont keep sliding off to the side when placed.



These injectors didn't stood a chance to a pair of 4 ton jacks. Also make sure you label where your injector goes to which cylinder, you don't want to mix it up or you'll run into no start problem.



While i'm at it I when ahead and pulled out the valve cover and do a deep clean and replace the valve cover gasket.



There was about 12 E10 bolts holding down the valve cover and a fuel/water drain line that is back of the valve cover, along with a couple wires and a cam position sensor to be removed.



That's all for this week im beat, Im now struggling to remove the injector copper washer, a few VW TDI folks have the same issue with carbon locking the injector seal and suggested using the one of these approach, A wooden tapered dowel to wedge/anchor on the washer and pull out, a small long cold chisel to split the copper washer (risky damaging injector seat), or using a tapered 7mm screwdriver to wedge into the washer, twist and pull to get it out.

[ROLLGUY]

Congratulations, and well done. It also helps to get the engine warmed up good before removing the injectors. When I did mine, I was able to pull five injectors without issue. The last one (#3) fought me for an hour, but my slide hammer and I prevailed. Pulling the cam cover is the way to go with a case of B.D. being that bad. It is going to look great when you are done. Keep up the good work!




EDIT: I suppose if I ever need an E10 socket, I know where to get one :-)

[tjts1]

Originally Posted by Actros617

LOL nope that's where I rip the engine out and part out the car.

[Actros617]

Time to wrap up this black death fiasco chapter and get her running.

Valve cover is nearly spotless, was cleaned with dilute 50% purple power cleaner and 50% water, some light sanding and soak in warm water. Result nearly spotless valve cover gasket. Injectors were given same treatment some light sanding and diluted water/purple power cleaner on the body and pick out all the carbon build up we took care not to touch the injector tips.




Next was the injector seals, they may appear to be stuck when dry but a spray of seafoam deep creep (great stuff), and a very wide flat tip screwdriver that will only come into contact on the washers and some short firm (not to hard) taps from the screwdriver will allow the penetrating fluid too work under the washer and eventually free it from the carbon lock, then it's a matter of scooping it up.



Next tackling of cleaning the injector bore and bolt holes. I used a injector seat reamer to clean the bores and blow with compress air. The seats were very clean and dosen't be cut (in my situation) then i proceed in using a wire bottle/bore brush to clean the injector bores and blow with compress air. And finally a shop paper towel sprayed with carburetor cleaner wrapped around long drill bit to mop the leftovers.




Place the valve cover on and then clean the injector bolts hole this will prevent junk from falling in to the cams. The bolt holes can be cleaned using 12 inch long drill bit (by hand!) to evacuate all the junk that has fallen in, followed by compressed air and a thread chaser tool (recommended) or an old bolt with grooves/flutes cut in it. This is imperative you don't want to hydrolock or snap your bolts while torquing them down.



After that is matter of dropping the injectors in and button things up! Inserting the injectors i put liberal amounts of ceramic grease on the body and on one side of the washer so it wont fall off when inserting, avoid placing on the injector tips! Reattaching the return lines (i replaced the plastics T return with aluminum ones) attach the injector lines (i snug tighten) reinstall the wire harness and plugged in it and fire it up! It took 3-4 crank cycles to get the fuel system to prime up but after that it runs without any problems, begone thy leaky injectors be gone!



Things to consider:
Torquing injectors, per MB it says 7 NM + 90° + 90° angle. What i used was 7 nm + 90° + 45° why because the additional 90* turn was an addendum by mercedes after production so the cylinder head injector
threads wasn't really rated for that kind of angle stretch thus why theres a few instances of stripping the threads and when i did the second angle turn at 45° the bolt feel like its about to snap and the threads about about to strip! Also with the liberal amount of ceramic grease placed on the injectors it should assist in helping seat and squish the copper washer using the original torque spec...Time will tell I guess!

Anyways next up, engine mount, this will be fun!

[Actros617]

New week and some warm weather, managed to knock out the engine mount, these things are a total pain to get out and but man do they make the differences at idle.

The both mount were completely blown out, the one on the left had lost all of its hydraulic fluid and the engine is sitting on the subframe sending very loud and abrasive vibrations in the cabin.


2 bolts only hold down the engine mount the short is located under and the long located on the top, the top bolt is not on very tight as most of the engine weight just sits on the mount.


To removed the mount the wheels cannot touch the ground or car ramps, which means your gonna need a put it on jack stands or else engine won't lift off it mount. To lift the passenger side mount place the bottle jack on the exhaust mount located on left side.


To lift the driver side of engine mount place place block of wood on the base of transmission bell housing with another bottle jack lifting the slightly right side of the transmission to lift the engine off the driver side engine mount.

[ROLLGUY]

Engine mounts- "been there, done that". Yes it is amazing how bad the sound and vibration is when they go bad. Just be glad you don't have an E500- The exhaust has to be removed to replace the mount on one side. On a Bluetec V6 (2007 and newer), the air box and heat shield on the right side needs to be removed. Of course having a lift is nice for this job, but it looks like you handled it just fine with ramps and jacks. There is a special tool for removing the top bolts, it makes it so much easier. Well worth the $ if you do these mounts......Rich