W115 240D Injection Pump Timing | Destroyer of Glow Plugs - Page 2 - PeachParts Mercedes-Benz Forum

MrWendell · #16 06-18-2011, 07:24 PM

One more note for those who attempt to adjust/pull the IP on a W115 chassis 240D:

I was able to access the 3rd bolt at the bottom of the pump by pulling the driver's side wheel. From there I used a 13mm socket with a universal joint and an extension. You can just reach it from the wheel well between the steering gear (pointed straight ahead)--way easier than trying to wrangle it unseen from the top or bottom using the 90 Degree wrench.

leathermang · #17 06-18-2011, 07:26 PM

Well, that IS good news... had no idea it had gone on that long..
Did you say whether or not you reamed your glow plug holes ?
I recommend that... anytime one is having glow plug problems.. when the carbon gets built up.. it shorts out the plugs in fast order...

MrWendell · #18 06-18-2011, 07:35 PM

I did ream out the glow plugs. Still waiting for the local Napa to get an order of replacement fast glows (80035), so I installed the two good I still had and put two that had their tips blown off back in--it still starts well even with the two plugs.

The local mercedes indy shop (definitely don't trust him anymore) had it for about 9 months trying to sort it out--finally told me it was bad compression. I almost sold the car a couple of times, but couldn't bring myself to do it. I kept thinking there was no way the compression could have changed that suddenly.

I should have had the guts to do the diaphragm myself in the first place--none of this would have even happened. Thanks again for your advice!

leathermang · #19 06-18-2011, 07:46 PM

Well, with the list of things you have done...and checked your list multiple times... that thing ought to purr for a long time with very little input... just go drive and enjoy it...
So tell me again why you now do not trust that MB shop ? LOLOL

Diesel911 · #20 06-19-2011, 12:52 AM

Quote:

Originally Posted by MrWendell

Just to be certain, there's no other reason that the fuel flow from the drip tube would cut at at that point--like from an injection on one of the other cylinders (but, those should only happen at another 360 degrees of crank rotation for #3 and opposite for #s 2&4, right?)

If you do not keep the Fuel Supply Pressure up and somewhat even the number of drips is going to be different.
If you are using the Hand Primer to keep the Fuel Supply Pressure up I have often advised to let someone else do the pumping of the Hand Primer while you do the Fuel injection Pump Twisting and Drip counting.

After the begin of injection I have no idea how many degrees the Feed Hole in the Element is covered.

Diesel911 · #21 06-19-2011, 12:55 AM

Quote:

Originally Posted by MrWendell

The car is FIXED! I took the plunge and pulled the IP with the crank set to 24 BTDC. Sure enough, the notch in the gear (looking straight at the front of the pump) was about 3 teeth to the left of the dot on the pump. Using a 19mm wrench, I moved the notched gear back in line with the dot on the pump and reinstalled it.

This time I was able to push the pump towards the engine and actually get the 1 drip/sec rate at 24 BTDC! I turned the engine over by hand and verified it two more times. Starting at 80 BTDC I get a constant stream from the drip tube until about 27 BTDC where it starts slowing to the 1 drip/sec at 24 BTDC.

I put everything back together and, after purging air from the injection lines it fired right up! Power is back to normal, it's quiet and it refires when warm with absolutely no glow--just like before all this drama.

It looks like the mechanic set the timing to ~45 BTDC--probably assuming it was the same as the fintails. Hopefully, no long term damage was done. Thank you all for your help--getting this fixed has been a year and half project!

Good Job!

DB444 · #22 11-17-2013, 10:44 PM

I bought a 1982 240D yesterday.
Clutch shutters a lot off the line.
Otherwise seems OK.
Car has very little power,less much less than other 240d's I've known.
Pump timing check?
How's that go,again.

barry12345 · #23 11-18-2013, 11:50 AM

It is really great for you to post the fix and to hear your car is running okay now.

Diesel911 · #24 11-18-2013, 02:35 PM

Quote:

Originally Posted by DB444

I bought a 1982 240D yesterday.
Clutch shutters a lot off the line.
Otherwise seems OK.
Car has very little power,less much less than other 240d's I've known.
Pump timing check?
How's that go,again.

In the case of this thread it sounds like who ever installed the used Fuel Injection Pump installed it wrong or badly botched the Drip Timing.

The OP rotated the Engine to 24 degrees BTDC on the Compression Stroke and pull the Pump of and found the timing marks on the Pump gear and Bearing Plate were 3 teeth off.
I corrected that and re-installed the IP and Drip Timed it and all was good.

The Drip timing method is the same for all that use the Drip Timing. The Timing degrees you need should be on a sticker up at the Front of the Car under the Hood along with the Valve adjusting Clearances.
DIY Repair Links
http://www.peachparts.com/shopforum/forumdisplay.php?f=82
http://www.peachparts.com/Wikka/DoItYourSelf

Beyond the above stuff when I first got My Car it was scary slow when you first put your foot into the Pedal. Once it built up speed it drove normally.
It turned out My Throttle linkages were extremely sloppy and what was happening is I simply was not getting enough throttle lever movement at the Fuel Injection Pump.
With the Engine Cold and it does not need to be running either. Grab a hold of the Throttle Lever on the Fuel Injection Pump and have someone step on the Accelerator Pedal and watch your linkages.
You will be able to see if there is a lot of play in them before the Linkages try to move the Throttle Lever on the Fuel Injection Pump.