The devil is in the details. That range of positioning might be two degrees on the IP............or four degrees at the crank.

I don't consider it an accurate way to set IP timing when an alternate means is available.

Does the alternate means take into account internal pump wear in the same way that drip timing does? With drip timing, actual start of delivery is observed, not inferred through an artificial reference point that is mechanically connected and subject to a different set of potential inaccuracies.

Your question is rhetorical, and, therefore needs no response.

Your point is noted............however the "internal pump wear" has not been quantified in any way to my knowledge. Therefore it cannot be used as a valid argument that the two methods will differ to a degree that is greater than the typical measuring inaccuracy of the drip method.

Did you accurately quantify, by measurement, the four degrees of alledged "slop" in the drip method? (I will admit to wondering if I can even read the crankshaft position to within a couple of degrees!)

Of course.

The error in reading the crankshaft position would compound the inaccuracy.

I have sent out for the rental A-B timing tool to set the timing, but in the meantime, for my own experiment, I may look at adjusting with the drip method.

I know there is a specific drip tube required, but is the drip tube height and length based on the pressure created by the primer pump. Meaning that the extra length and height of the factory injection line will not allow a steady flow of fuel in order to perform this procedure?

Just wondering if anyone has performed this method with a factory number 1 injection line (full length)?

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1985 300SD 200K

There is nothing magical about the drip tube. It simply allows one to observe a drip. Any tube, of any length, connected to the IP will serve the same purpose, once the tube is filled with fuel to the point of spillover.

Thanks I might try that injector line just for an experiment until the rental A-B tool arrives.

Quick question though, does anyone have a special trick for loosening the front injection pump bolt? The one between the pump and the engine block. There is a black rectangular box above it which doesn't allow any room to get to it.

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1985 300SD 200K

You access that screw from the rear with a universal and about 9" of extensions so that your ratchet is slightly above the pump and away from the engine.

Thanks to mbdoc I was able to rent the A-B tool and set the timing to ~14.5° ATDC (just before the 15 mark on the damper). This was very easy to do. I noticed though that others suggested to set it at 14° so I might try that. Is that the maximum advanced safe setting for this car?

I did not noticed a huge performance change off idle as it still takes about 5 seconds to get to 20 mph. It is slightly more responsive though as it seems like there is less of a dead spot (low power area) between 1000-2000 rpm.

I think I will look into the Alda adjustment next.

Would getting my injectors pop tested benefit the throttle response?

I really want to get this car in better running condition as there are numerous hills in my area which seem to present a challenge to this car at times when starting out.

Thanks for all the help.

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1985 300SD 200K

After driving the car to and from work today, I really don't notice any difference from before I timed the injection pump and now.

Car timed at 14.5° ATDC and I have not adjusted the ALDA yet.

I timed the 0-60mph runs today and they are right around 18-19 seconds. 0-20mph is around 5 seconds still.

I am confused, I feel like timing the pump didn't do much for the car. Are the pump internals worn out enough to not make a change in timing less noticeable or does this warrant checking the camshaft timing?

Also, this morning was around 30°F and the car started up but surged a few times and once it stalled. Re-started, gave it a little bit of idle and it was fine. Could this be air in the system? I thought I remember reading that the car has an automatic air bleed? Maybe it is pulling in air after sitting for a bit?

Any input is appreciated.

Thanks.

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1985 300SD 200K

ATDC ? this is after top dead center. I assume you mean BTDC?

These pumps do not seem to wear out easily, so no I would not think the ip is worn out, unless bad fuel or wrong fuel got to it.

I would check cam timing, but would not expect to see big differances in performance, unless it was really off. It is just good to check so you know one more thing is in proper order.

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1977 240D turbo

He's timing it per the A/B lights via the port on the side of the IP.

The spec is 15ATDC...........he's just slightly early.

Yep.

Don't break the screw!

You can remove the ALDA if you want the ultimate test. It's a two minute procedure on the 617 if you have a thin wrench (25mm???)

So while I still have the A-B tool, I retimed the IP at 14 ATDC as was suggested. That tool makes this job very easy, about 1.25 hours for me to complete it.

Anyway, before jumping into the alda, I decided to look at the linkage again, which before looked like it was working properly, but this time the first 1 inch of pedal movement takes up the slack in all the linkage befoe the throttle lever on the IP even begins to move. At full throttle, there is about 0.25 to 0.375 inch gap between the lever and the stop. I am thinking this may play a big part in the lack of off line power. I will look into adjusting these, but does anyone have any hints on where to start? Should I extend the rod attached directly to the pump throttle first? Or start at the rod attacherd directly to the pedal lever? Any help is appreciated. Thanks.

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1985 300SD 200K