ok im going to try to do better 1982 300 sd turbo. nos 4 and 5 injectors leaking fuel. would it be the line or something else? should i try to tighten the line with regular wrench? as always thanks in advance. Bobco

Hey bob

How many miles on your benz and how much money do you want to throw at it. I just replaced my injectors with new ones at 240000. I figured that it could not hurt to have new ones in there. You can try tightening the fuel line bolts but dont go to tight. (around thiry pound of torque).

Your fuel return lines may be bad (those rubber ones) if you change them get original MB.

I put in new injectors in about one hour and $300 in parts.

If you like you can take it to a shop and have yours tested but i figured for that much money i could just replace them all saving labor cost.

To save money the first remedy would be to change the rubber fuel lines and rubber stop at #5 and reset the metal fuel lines. If that dont do it you may need new injectors. whether or not you replace them all is your preferrence.

good luck

bob

hey bob,

I'm actually interested in changing out all my injectors in my 300D 78. How do you go about and doing this? is there specific type of procedure to do it or can i just pull out all of the bad injectors and stick in the new ones without priming anything? Also everyone in this room had their injectors done by some specialist for correct nozzle output. I was thinking of ordering my 5 injectors but i'm not too sure if they do a really good job in fine tuning the nozzles.

Also if you can...list the parts that you recommend that is necessary in changing out the 5 injectors (I.E rubber hoses, etc)

I bought my injectors from MB, my brother gets a employee discount. If not I would go to fastlane or some other distributor of bosch rebuilt injectors with the correct pressure output. I dont recall what the correct pressure is but my rebuilt injectors were within that range. I believe what you are talking about is if you rebuild your own. I hear that it is not that hard but I did not bother with that.
changing them is easy less that one hour
1 Remove the spiderweb metal fuel lines with 17mm open box wrecnch. a 17mm brake line wrench is even better but not manditory
2 Remove the fuel lines (rubber) from the injectors and the fuel pump. You can not reuse fuel lines as they may not seal with the new injectors
3 Remove the injectors with a deep socket 27mm. Be gentle with them. I bought and recommend using a big torque wrench. It gives you great leverage and is necessary for proper torque specs, it is now my favorite wrench.
4 Remove and replace the washer below the injector (heat sheald) not the position of the washer I think that it is tapered side down.
5. Install new injector to specified torque (55lbs?)
6 Install metal fuel lines do not over tight 30Lbs
7 Install new rubber hose and end stop

That is it
Then you prime the fuel system using the pump down by the fuel pump... pump the pump until you dont hear any more hissing out of the fuel filter area

good luck

bob


so new injectors, new fuel line (buy more than you need in case you mess up), and heat shealds.

then forget about your injectors for 200000


PS I strongly believe in filling up my cars at half tank so that I dont run much crud through the system.

hey bob,

thanks for replying...i'm pretty much confident in changing out my injectors myself now....One thing though..
I went to the fast lane website and looked at the fuel return hoses. They are selling them at 209mm lenght..is that enough for my 300D? Also i looked up the heat shields you were talking about, but at fastlane, they offer two types of measurements...at 7.5mm and 10mm offrice...which one should i get? Last, do you think i should change out the fuel filter if i'm going to change out the injectors? I just had the fuel filter replaced about 4000 miles ago...will i see a big difference?

thanks again
Allan

I dont remember how wide they heat shields were. try calling your local MB dealer and see what they say. IF you want to get the part number from them and order through fast lane. do the same for the fuel line. I dont recall the amount of fuel line that they gave me either but it was just enough. So maybe the measurement they give is just that. I would have preferred to have more though in case I made a mistake. IF it is not alot of money order two of them and you got a back up for next year or go to MB and order a little more than the minimum they should have it by the foot.

the fuel filter should still be good but if you want to change it no problem with me. I am going to change mine every 6 months. It is cheap and easy insurance that I got clean system. More importantly fill up at one half tank. I owned many diesels and had no engine problems.
I put over 120000 miles on a car without changing the fuel filters. I was stupid for that but I alway filled up at half a tank. Now I will change the filters at least once per year and still fill it up the same way. You also dont get into the hassle of looking for diesel when your on empty.

also my 300d made some ticking noise for about 10 minutes after doing the job. It went away and I was happy again so dont be surprised if this happens to you.


good luck

bob

Hey allen

I hate to throw you a plug for business. I would suggest doing business with fastlane as it would benifit the forum. The reputation of their service is good and the gentleman (I forgot his name) who will facilitate your order if you call him is very helpfull.

good luck

bob

Hey Allen

I found my reciept witht the part numbers that I put in my diesel

Injectors 002 017 20 21 88
Heat Shield 601 017 00 60
Fuel hose 605 078 05 81

Hope this helps

later

bob

I have an 1982 240D.

479,000 miles, 190,000 on rebuilt engine.

I had some serious nailing/missing and narrowed it down to the #4 injector.

(Loosened fuel line nut, miss stayed the same).

I ordered two "good" used injectors off e-bay from a reputable source.

Installed "new" injector.

Nailing and missing went away for about 50 miles.

Back now worse than ever.

I did NOT replace the heat shield and motor is now missing on #4 and #2 cylinders.

Here's where it gets a little strange.

Once the vehicle is warmed up, it will idle and run with no miss and the nailing nearly goes away, intermittently. Sometimes (when warm) it runs perfectly, sometimes I'll still have nailing, or a miss.

SO, I am thinking of ordering new Bosio nozzles and rebuilding all the injectors.

Ideas/Comments/Suggestions??

I do run a two tank WVO system (have not been using WVO since the nailing showed up) ...

__________________
1982 240
460,000 miles total
140,000 on Rebuild

The originals bosch injector nozzles were made in germany the new ones are made in India and have major quality control issues, some people report failures after 1000miles should go with italian brand nozzles like bosios or monarks, especially if running wvo. Also do not generally need to replace the whole injector just get new nozzles and bring to diesel shop to rebuild. rebuilding requires more than just installing nozzles as shims must be placed within injector to get correct pressure/bar rating, whcih requires different shim sizes and a pop testor. generally injector nozzles are supposed to be replaced every 100k miles from what I have heard and should make a huge improvement with economy and nailing, rough running etc.

I had bought 2 sets of "Running Pulls" Injectors on Ebay. All of them were worn out.
Unless you buying used Injectors as Cores to rebuild I would not trust them to be good.

The only way to know for sure if a used Injector is good is to have it tested on a Pop/Nozzle Testor.

Also, when you (Loosened fuel line nut, miss stayed the same). That only told you that that there was a problem in that Cylinder.
You have to swap the suspected bad Injector with a known good Injector on the same Engine.
If the problem follows the suspected bad Injector to the new location; you know know it is the Injector that has a problem.

__________________
84 300D, 82 Volvo 244Gl Diesel

I have a source for shims and I have a homeade pop tester (made from a bottle jack)

Is this not accurate enough?

I'll try moving the injectors and seeing if this corrects the miss in #4.

It just seems odd. Tonight, when I drove it home from work (about 45 degrees ambient temp) She started fine, began missing right away and when she reached 80C the nailing and miss gradually went away.

Is there anyway there could be a problem with the IP? Seems VERY improbable since I get fuel to the injector and there does not seem to be a problem universally with the other injectors. Is is possible the IP is not delivering enough fuel pressure to #4 to make it fire correctly?

I had that thought but had ruled it out since I see raw fuel (and smell) coming out of the exhaust, which tells me that the injector is getting fuel and "popping" but that the spray pattern is puddling, rather than misting.

Maybe I'm way off. I was a gasser mechanic for years so this is all new to me.

having a site like this has been invaluable though!!!

__________________
1982 240
460,000 miles total
140,000 on Rebuild

If your Homemade Pop tester works OK there should be no problems there.

There is a DIY on rebuilding the Injectors. Did you find and read that?

Also, What do you plan to Lap the Precision Flat Survaces with?

It is also easier to shim the Injectors if you keep all the parts of one Injector with that Injector.

Also in the pic below there are 2 styles of Injector assemblies. Both can be used and even mixed together on the same Engine as complete Injectors. But, with the exception of the Spray Nozzle; the parts cannot be interchanged.

Attached Thumbnails

 

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84 300D, 82 Volvo 244Gl Diesel

In the below pic the red arrows point at the precision surfaces that need to be lapped. The double arrows pointing to the 1 part indicate that top and bottom need to be lapped.
The flatness of the surfaces and the proper torque are all that seal the Injector inside.

Also anything; even lint that gets between those surfaces during assemble can case a leak. No big deal; just take apart the Injector clean and if need be lap again.

Attached Thumbnails

 

__________________
84 300D, 82 Volvo 244Gl Diesel