I tried "search" but couldn't find a direct answer. I own a 92 2.5 TD and the injector pump is leaking badly around the bottom of the pressure valve housings. I read in another thread you can replace them DIY, but it didn't specify which year vehicle was in question. I've been told by a very experienced mechanic that once you open those pressure valve housings to replace the washer and seal, the unit (pump) must be recalibrated to deliver the proper cc's of fuel. I don't want to go cheap and blow a perfectly good engine. Worst case, I can get the pump rebuilt for $600. Taking it out is no big deal except for that pump locking tool that holds the mechanicals inside when removed. I want to do this right, and if it's expensive then so be it. I just want the straight scoop!

Terbodude,
This is an easy diy project. Timing or pressure are not changed with this repair. We have replaced many o-rings without any problems. Remove the fuel lines, If the intake is removed this job is easier but it can be done, then using a special socket remove the pressure valve and replace the o-ring. All DIYers should purchase the repair cd. This programmed repair is explained in detail, job 07.1-8627 on the repair cd

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Paul

Thanks Paulwho!
I ordered the copper sealing washers and o-rings. Special socket is on the way too. I have the MB service CD's but couldn't find the repair anywhere. I wish they had a search function. Do you know the torque spec in ft. lbs. (or inch lbs) for the pressure valve housings? Are there any seals of any type at the injector end of the fuel lines when I remove them? Bleeding after assembly? How about any tricks or tips? Anything else I should do while I have all this apart? ( I just had the intake manifold off a month ago to change glow plugs. ah, hindsight).
Thank you!

I need to do this on my 87 SDL, I too have the disk and can find the valve diagram but no info on the proceedure for seal replacement. Step- by- step would be invaluable.

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N. Hodges
1994 S350
1987 300 SDL (for sale)

Easy job with only one "gotcha":

Clean IP (no dirt in the injetion system, please!). Remove injection lines on both ends and set asside (note that you will probably need new plastic clips, they all break when you unclip them, and the lines will fatigue if you don't have them clipped down....).

Not arrangement of the lock rings and remove. Screw will be very tight -- no antisieze at the factory, I think. Lift off rings.

Unscrew pressure valve holder (I recommend on at a time) and lift off. Watch for the spring, it tends to stay in the holder if you don't pull exactly straight up, then falls out and drops on to the dirty floor.

Copper seal is sitting on top, lift off with a pickand replace with new. Remove old o-ring from holder and install new.

Put spring back in place if it came out, then fit holder back in. Run down finger tight, then tighten to 25 ft/lbs TWICE without loosening, then again without loosening, to 30 ft/lbs. Failure to correctly torque is the only real problem here -- the seals will leak of you don't torque properly, and that will cause serious injector knock and loss of power caompanied by severe engine shake (affected cylinders don't fire at idle). Got my 300D cheap because fo this..... If you get these symptoms when you restart, loosen and retorque the pressure valve holders.

Refit lock rings and pre-load gently to hold pressure valve holder tight, then tighten screw. Please use some antiseize.

Refit injection lines to pump and injectors, but leave injector end loose by about 1/2 turn. Crank engine with your foot to the floor until all the air is purged out of the lines, then tighten cap nuts and crank til it starts.

Best to do this with the engine hot -- easier to start that way.

Peter

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1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!

Hi Paulwho,
Did the job today. Piece of cake. Removed intake manifold and the crossover pipe, which was caked with 1/8th+ of an inch of baked on oil from the crankcase vent, removed lines and replaced said parts. All went well and no leaks. It did take over two hours to clean out the intake and pipe and can just imagine what the intake side of the turbo looks like. I replaced the springs too because it said "renew" on the CD. The car started after bleeding the lines, however now it seems to do that diesel knock/chatter at idle a lot louder. It silences as soon as you increase RPM's. Even after warming on a short drive (5 mi.) it still seems a lot louder at idle, but runs just fine. Any ideas?
Thank you!

Treat it to a nice drive on the highway.

Unless the knock is isolated to one cylinder, it's probably just air in the lines -- takes a while to blow it all out.

Peter

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1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!

Going to take it on a 37 mile highway cruise tonight. Thanks psfred!