First R&R of Injectors . . . Is this procedure correct? - PeachParts Mercedes-Benz Forum

EDBSO · #1 12-07-2012, 12:31 PM

1999 E300 Turbodiesel

This will be my first time doing a R&R of a fuel injector, I have replaced many spark plugs over the years so the concept is not new to me.

What I plan on doing is removing the hard injector retainers to provide more room to move the hard lines aside.

I expect them all to be brittle and break and have new ones on hand.

Next I will loosen and remove the nut holding the hard line to the injector.

Removing the braided fuel return lines is a bit unclear. Are they slightly heated or simply reefed on till they come off? Any special techniques as I believe they will be really stuck on.

I have a 22MM deep socket to remove the injectors. Is it best to do remove the injectors on a hot, warm or cold engine?

I plan on moving the hard line only enough to get the socket on the injector.

I will cover the holes with paper towels to keep dirt out.

I will then have them cleaned, rebuilt and pop tested by a local shop. I have new heat shields and believe that the rebuilt injectors should be torqued 50 to 60 foot pounds.

What pressure should the new Bosch Nozzles be set to pop at?

Any tips or techniques that can make this job easier? I am cautious and a bit concerned about doing this for the first time.

Thanks

EdzBenz · #2 12-07-2012, 02:34 PM

Looks like you've got a decent plan here. I replaced the headgasket on my E300 and have done this procedure. Here's some tips:
-You're right. The hard plastic injector retainers will probably break
-I'd recommend removing the hard metal fuel lines completely. The last thing you want to do is risk bending or breaking them. Plus, it's a tight fit getting at the injector. I realize this requires you to remove the intake manifold, and take more time, but this is just how I would do it. Plus, you can replace the brittle fuel lines around your injection pump while its off.
-Expect to replace the braided fuel lines. They will be brittle too. Replace them with Viton line while you're at it. Just pull the fuel lines off. There are two nipples at the top of the injectors that they are attached to. Its a press fit.
-If you use viton, and not stock, for the fuel lines, be absolutely sure you have a tight fit to the injector when back on. I didn't on my #6 injector and spray fuel all over the place when I was on the highway. You can use a metal bread bag twist tie to help keep it in place if need be.
-I removed my injectors on a cold engine. No problems here. Just take care in removal.
-Good idea to cover the holes with paper towels.
-Just take your time and map all of the parts out so you can reassemble properly.

Diesel911 · #3 12-07-2012, 02:56 PM

I agree on othe Injector Return Lines; they are going to need to be replaced. Even if you got them off OK if reused even if one of them came loose later it would be a Big Pain and the loss of Fuel could exceed the cost of the New Hose.
Just give them a Yank and worry about getting the rest of the Hose off of the Injectors after the Injectors are out.

Clean your Engine off before starting if it is dirty.

Unless Injectors are rusted in place (unlikely on your Engine where everthing is more enclose) no need to remove them Hot.

Not needed but if you wanted to you could put a little Neverseeze type compound on the outside Injector Threads. That is more useful on the older Engines.

I noticed when you drop Heat Shields down the hole they tend to fip over and over and may or may not land on the side you want. It it Better to slide them over a Phillips Screwdriver of other similar item and stick that to the bottom of the Hole and let your Heat Shield slide down the Rod.
Even then it is a good idea to get a strong beamed Flashlight and look down and check that they are right side up.

If you have compressed Air before you re-install the Fuel Injection Hard Lines blow them out to remove any possibility of dirt getting into your rebuilt Injectors.

I have been know to tape over Plastic Bag the Injector ends of the Hard Lines because while you are attaching them to the Fuel Injection Pump the tops are polking all over and have a chance to pick up some dirt from the Engine.
When I did that on the Job I used Cap Plugs; since I did not have to pay for them.

TMAllison · #4 12-07-2012, 05:43 PM

You should double check the torque; sounds too high. Maybe you meant NM's rather than foot lbs.

Do yourself a favor and go for inj #1 to be certain your socket will reach/fit before removing the IM or too much else. The factory tool has a slot in it to clear the return line barbs. You don't want to scratch or bend those. It is also ~4.5" long and very thin walled....

Doktor Bert · #5 12-07-2012, 06:57 PM

From my dealership days - Tips for rapid injektor swapping:

Swap 4-5 injektors and start engine.

Swap 2-3 injektor and start engine

Swap #1 injektor and start.

Instant start, no bleeding necessary....

Doktor Bert · #6 12-07-2012, 06:57 PM

Quote:

Originally Posted by Diesel911

I noticed when you drop Heat Shields down the hole they tend to fip over and over and may or may not land on the side you want. It it Better to slide them over a Phillips Screwdriver of other similar item and stick that to the bottom of the Hole and let your Heat Shield slide down the Rod.
Even then it is a good idea to get a strong beamed Flashlight and look down and check that they are right side up...

Good tip....

dieselmania · #7 12-07-2012, 10:37 PM

I learned from a diesel shop to sray the tips of the lines and the tops of the injectors with brake cleaner just before putting the lines back on. I did this on my Ford and on my 603 and never had a dirt issue. It also helps to have a very clean engine to start with.

vstech · #8 12-08-2012, 07:35 AM

I will +1 on the do not bend the lines out of the way!

loosen the nuts at both the injectors, and at the pump, and with the clips removed, the lines will easily move out of the way. No bending needed!
taking off the intake manifold should not be required to do this.
if however, you plan on changing glow plugs to have new everything with the new injectors (it's winter time after all...) the intake should come off. plus the crossover and intake could be heavily gunked up with EGR crud, so removing it for cleaning is a good idea.

EDBSO · #9 12-08-2012, 11:58 AM

Thanks one and all.

I will pay attention to cleanliness.

New braided return lines will be used.

Very reluctant to remove the intake manifold, winter here and in an unheated garage just too much!

Love the sliding of the heat shields down a Phillips screw driver.

Will wrap the line ends in plastic wrap to keep them clean and hit them with brake cleaner just before assembly.

Love the idea of just loosening the hard lines at the pump enabling them to turn freely.

What pressure should the injectors pop at and how much should they be torqued to? I don't have access to the WIS.

My "Indie" just might get this job after all?

KarTek · #10 12-08-2012, 11:15 PM

Here's some answers for you:

You don't have to remove the intake manifold.

The injectors pop at 135 bar for the turbo cars and 115 for the non turbo.

Don't loosen the lines at the pump because it just increases the chances of a leak.

Before you remove them, make sure the shop has the proper shims. They're much smaller than the OM617, 616, 603, etc... Something like 10mm if memory serves me.

The injector torque is much lower than you would think. Something like 28 lb/ft but I don't have ready access to the exact figure.

Hope that helps.

OK, correction, it's 40 NM or about 30 #/Ft.

EDBSO · #11 12-09-2012, 12:22 PM

Thanks KarTek, like so many jobs there are many ways to do the them.

Waiting for the final pieces and a slightly warmer day.

Thanks again to all and MERRY CHRISTMAS

EdzBenz · #12 12-10-2012, 05:03 PM

Good luck. Let us know how it all goes.

EDBSO · #13 12-13-2012, 05:15 PM

Lack of progress update.

I need the proper 22mm injector socket.

Purchased a Lowes deep 22mm and carved out space for the return line "ears" as per this.

and side shot

and the thin walled socket is too thick to fit down the injector hole/well.

Put the hard line and return lines back on and trying to source a proper injector socket.

Recommendations on where to get a reasonably priced 22 mm injector socket please . . . One that will fit!!

KarTek · #14 12-13-2012, 11:37 PM

Get the crappy Harbor Freight 22mm deep socket like I did... The return line nipples don't stick out beyond the diameter of the injector. (well, at least not enough to matter) You won't have to cut any reliefs in the socket.

TMAllison · #15 12-14-2012, 11:40 AM

The OD of the factory socket is a shy 1.125" and the length is 4.375".

It has one .75" x 2.75" notch cut out of it that is centered on one side of the socket on one of the 3 "flat" legs of the six sided socket.

The inside of the socket is milled out ~.125" x 1.375" where the second return line nipple would reside.

I have the Inj socket and the DV socket if anyone is interested in purchasing them. Have various other 606.962 pieces and parts too.