1985 300D with 365k miles, bought 6 months ago. 22 city/24mpg highway (@75mph) 0-60 18.5 +/- seconds (oversized tires)

I have done the diesel purge, gutted veggie crap, adjusted valves, changed filters, 5 new glow plugs, an oil change, bypassed vacuum leaks and transmission fluid drain and filter change.

After doing a significant amount of reading and searching, I decided that the last real engine maintenance item that I needed to do was time the injection pump. I was wanting to get rid of the poor idle and shaking at occurs under 1000rpms, as well as see if I could improve my miles per gallon.

After reading, it looked like the bubble method of timing would be the best course of action. I took unhooked and removed the spring and delivery valve, hooked up my air tube and started to blow.

The bubbles stopped and I checked where the mark was, to my surprise it lined up right to the empty void. Not looping hope I did another rotation, this time the bubbles stopped just to the right of the dimple/crater/depression.

Neither one was ANYWHERE close to a set of timing marks!!!

I pressed on and tried to just set the engine to 27 btdc and call it a day. Couldn't get all the nuts loose, lost the wrench in the garage 2 times, searched and research the internet then admitted defeat and had to start looking for a ride to work.

Started the job at 10am and kept at it till 4pm. Surely it can't be this insane.

I'm at work at the moment, but I'll try to snag some pictures after I get back to the house.

Any help would be a major plus!

P.S.

I don't have any way to get a drip tube, no PnP yards around here that have older Mercedes.

I timed mine by pulling the number 1 delivery pipe off the IP and blowing the fuel out of the port in the pump. Then rotate the engine VERY slowly(helps if the glow plugs are out) and see where the fuel starts filling the port in the IP, then STOP turning the engine. Then compare with the timing on the balancer. Took me a few attempts, and then about ten more rotations to verify that it was where I wanted it. It's probably not perfect, but the engine runs well, gets good economy, and has good power.

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617 swapped Toyota Pickup, 22-24 MPG, 50k miles on swap

I used the Fuel Injection Pump Timing/Locking Pin the last time I did mine. That is the method that takes the least skill to do.
You 1985 Engine if it has the original Fuel Injection Pump will have the port for the Timing/Locking Pin.

Fuel Injection Pump Removal with the Oil Filter still on 617.952
Fuel Injection Pump Removal with the Oil Filter still on 617.952 - PeachParts Mercedes ShopForum

I cannot comment on the bubble method as I have never tried it.
I have done the Drip Method. A little time consuming as I had not done that since the 1970s but it worked (I was trained at work to do the Drip/Flow Timing Method so at one time I had a lot of practice at it).

2 things they help you no matter what timing method you use.

One is to scribe a mark acrossed the Fuel injection Pump Flange and acrossed the Engine Block so you can get the Pump back to the same spot if you have trouble.

Two remember you are only going to need to move the Fuel Injection pump a tiny amount (your timing is only going to be a degree or 2 late) and that is easiest to do if you disconnect all of the Fuel Injection Hard Lines.

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84 300D, 82 Volvo 244Gl Diesel

It's not uncommon to need so much adjustment that the pump needs to be removed and reindexed. Any notion that only one or two degrees of adjustment will be needed is completely without basis, especially with 365k miles and unknown history.

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When cryptography is outlawed, bayl bhgynjf jvyy unir cevinpl.

Check timing chain wear, it can really affect your IP timing.

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Cheers!
Scott McPhee

1987 300D

Remove the valve cover and check the timing mark on the cam to the one on the crank....make sure you timing chain is not servery stretched...

To do the timing, you must make sure cyl 1 cams are rabbit eared...the throttle is fully opened and have the thing to do the drip timing...its rather simple....but takes practice...

I would bet my life your problems are not do to the ip timing but rather poor mounts, clogged filters, clogged lines, clogged tank, bad engine shocks, rack damper bolt, fuel pressure relief valve, injectors, lift pump, air filter....

So many things can cause a rough idle...

specially if they used wvo....you may never get rid of the idle issue

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That normally happens when someone has previously removed the Fuel Injection Pump and re-inserted the Fuel Injection pump without centering the Kidney Slots in relationship to the Bolt Holes or Studs.

An other issue can be they inserted the Fuel Injection Pump at the correct Degrees and managed to bump the IP Camshaft to rotate it when the inserted the Fuel Injection Pump (the very thing the Timing/Locking Pin is supposed to prevent).

Anyway that is my opinion on it.

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84 300D, 82 Volvo 244Gl Diesel

That's a great theory. But the witness marks often tell a different story; typically, the pump hasn't moved since it left Stuttgart.

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When cryptography is outlawed, bayl bhgynjf jvyy unir cevinpl.

I adjusted the injection pump in my 84 300D just yesterday, for the first time. It was very difficult to get at 2 of the 4 nut/bolts.

The rack position sensor is in the way for the top-right nut. I had to spend a lot of time to get just the right combination of sockets and extensions to get my 3/8" socket wrench into the narrow gap where you can swing it, just aft of the sensor. I also had to jam a screwdriver against the extension to hold if for the clicks.

The aft bolt (below vac shut-off valve) was tricky because I had to swing a wrench in the small gap between the oil cooler tubes. I used a Craftsman 13 mm ratcheting box wrench that has fine clicks. I was able to loosen the bolt, barely getting the next click. But in tightening, I had to remove the wrench each time and turn the head manually for the next click, which took a long time.

I adjusted the IP on my 85 300D a month ago, and recall it being much easier. That car has an 82 engine, which doesn't have the rack position sensor. That sensor is only used for the EGR controls, which I bypassed anyway.

I never fooled with making a "drip tube", as shown in the manual. I just remove the #1 fitting on the pump. Before "start of delivery", the fuel squirts out, as you pump the primer. The "start of delivery" is where the flow gets blocked. It is a pretty sharp point, changing from squirt to nothing in ~1 deg of crank rotation. The 1 drip/sec is probably an anal spec the writers had to put in to quantify the process. I set both cars to 27.5 deg BTDC. Both were at ~24 deg BTDC as found, which is the factory spec. Both timing chains showed no stretch per the camshaft mark.

I can't say I really noticed a change in the way the engines run. Indeed, I found 3 injectors in my 84 engine were non-turbo (popped at 1600 psig), but it runs about the same now with 5 turbo injectors (1950 psig pop). Both engines shake a little at idle, and smooth out at higher rpm.

Not at all. The idea behind the drips per second is to get the Element Plunger positioned just before the Fuel Inlet/Feed Port is closed by the Element Plungers upper edge of the Helix.
This provides a spot that is always the same if you the Fuel Pressure steady during the timing.

Doing it the way you stated:
After the Port is closed the Fuel Flow you are speaking of will be stopped but it is possible someone to move the Punger Further for many degrees (especially in the Full Throttle positon) as the Fuel Flow will remain stopped until the lower edge of the Helix on the Element Plunger opens (ending injection) the Fuel Inlet/Feed Port on the Element. When Injection ends you will also get Fuel Flow.

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84 300D, 82 Volvo 244Gl Diesel

Never use the bubble method, in particular on the 85 IP.

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http://superturbodiesel.com/images/sig.04.10.jpg
1995 E420 Schwarz
1995 E300 Weiss
#1987 300D Sturmmachine
#1991 300D Nearly Perfect
#1994 E320 Cabriolet
#1995 E320 Touring
#1985 300D Sedan
OBK #42

Kind of lost you. I didn't state exactly how I did it. I thought I followed the book: i.e. manual pump the "lift pump" as you slowly turn the crankshaft, until the output changes from a continuous flow to ~1 drop/sec flow. All I said was that I see a very quick change from a good flow to almost no flow in about 1 deg on the crank, so trying to count drips seems silly and I doubt the special "overflow tube" shown helps much. There are many special tools shown in the M-B manuals that are either "no longer available" or "never existed". Ever seen a cylinder-sleeve removal "self-made" tool in person? Same for the Mopars I also work on.

It was hard for me to move the crank just a little bit. I had to hit a long wrench with the palm of my hand a few times to budge it, hopefully in not more than 1 deg increments. Therefore, I can't keep pumping continuously, so tweak the crank, pump, watch the flow, repeat. Perhaps I could get more finesse on the crank by putting the wrench on the crank bolt, but been there (can't see the marks while underneath), so I wrench the p.s. pulley bolt pulley like most people do. Some here fuss about that, but it isn't their car.

My recommendation is that if you have a later IP pump with the position sensor, it it shows the factory 23-25 deg BTDC timing, better to leave it alone rather than try for the 26-28 deg some here recommend. I didn't notice a difference in performance by advancing it. It will mainly help mitigate timing chain wear over time.

You are doing it wrong, you adjust the ip, not turnk the crank?

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http://superturbodiesel.com/images/sig.04.10.jpg
1995 E420 Schwarz
1995 E300 Weiss
#1987 300D Sturmmachine
#1991 300D Nearly Perfect
#1994 E320 Cabriolet
#1995 E320 Touring
#1985 300D Sedan
OBK #42

That would depend on one's objective. To determine the current start of injection, rotating the crankshaft is appropriate.

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When cryptography is outlawed, bayl bhgynjf jvyy unir cevinpl.

Of course you can use what ever method suits you.

I was trying to explain why the drip Method is used. The info might be useful to someone else.

And I was responding to what was said below:
"I never fooled with making a "drip tube", as shown in the manual. I just remove the #1 fitting on the pump. Before "start of delivery", the fuel squirts out, as you pump the primer. The "start of delivery" is where the flow gets blocked. It is a pretty sharp point, changing from squirt to nothing in ~1 deg of crank rotation. The 1 drip/sec is probably an anal spec the writers had to put in to quantify the process. I set both cars to 27.5 deg BTDC. Both were at ~24 deg BTDC as found, which is the factory spec."

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84 300D, 82 Volvo 244Gl Diesel