OM606 still Nailing and I'm stumped..... - PeachParts Mercedes-Benz Forum

KyleMP012 · #1 06-14-2018, 12:25 PM

Well I have a 1999 E300D, and it is persistent at nailing. The injectors are rebuild with Bosio Nozzles, new head shields, torqued to spec. Just replaced the delivery valve seals and copper washers with no change. Ran diesel purge and it was damn near scilent! As soon it was back in the diesel it nailed again. I have seen another thread about the delivery valves themselves being bad. Does anybody know the part number for them? (The delivery valves are the actual threaded items that the vinton seal goes on correct? Or is it the item that gets the copper washer in the pump?) The only other thing I can think of is a bad injector, because greazzer said 3 of them were practically seized together. Maybe they are failing internally? Jone of them leak. Thanks in advance!

ROLLGUY · #2 06-14-2018, 12:29 PM

Quote:

Originally Posted by KyleMP012

...................I have seen another thread about the delivery valves themselves being bad. Does anybody know the part number for them? (The delivery valves are the actual threaded items that the vinton seal goes on correct? Or is it the item that gets the copper washer in the pump?) ..............

The threaded part with the Oring is the delivery valve holder. The delivery valves are inside/below the holders.

KyleMP012 · #3 06-14-2018, 12:32 PM

Thanks! I'm pretty good with finding everything part number wise on the car, but the IP is hard to find internals for. The delivery valve older is the item I'm looking for then!

tjts1 · #4 06-14-2018, 12:47 PM

Check your fuel pressure to the pump.

jake12tech · #5 06-14-2018, 12:48 PM

I wouldn't really worry if the car runs fine..

The delivery valve springs are probably worn out causing the nailing.

KyleMP012 · #6 06-14-2018, 01:00 PM

I had ordered springs but the ones that came in were much shorter. I assumed the ones for the 603 were the same. The nailing is just so loud I can hardly place an order at a drive thru without turning the car off haha. It clears up past 1300 rpm

jake12tech · #7 06-14-2018, 01:06 PM

different pump, different springs. order them from MB. The pumps are internally different I believe the 606 has large delivery valves by half a MM

KyleMP012 · #8 06-14-2018, 01:12 PM

Does anyone know the part number for the DV itself? The spring was at least 2 mm taller and double the diameter compared to 603 spring

nelbur · #9 06-14-2018, 04:51 PM

I had a persistent nailing problem with my '97 606. One day I decided to remove the plastic cover and run it so I could use a stethoscope to find which injector was causing the problem. With the cover removed I started it up, and had no nailing. It has been nearly a year now and no nailing, and no cover.

Maxbumpo · #10 06-15-2018, 07:49 AM

Kyle,

You don't want the DV holder, you want the DV, which is probably a small barrel with a plunger. The copper sealing washer goes under the barrel, the plunger goes in the barrel, and the spring pushes the plunger down into the barrel.

There are two places that I know of where the DV assembly goes bad. The bottom of the barrel can get scored or otherwise damaged (usually a human-caused issue) and the seat where the plunger fits the barrel can get worn and rough (this is more likely the case when bad fuel with water is used).

If you take apart the DVs again, you can check out both ends of the barrel. Note that you will need new copper washers and O-rings for each DV.

Source for parts: These things very rarely wear out, so if you can find a used injection pump you can probably re-use the DVs. Check with a Bosch shop that services injection pumps, they can probably order new DVs for you. Maybe contact Myna or one of the other IP super-tuning places in Europe to see if they'll sell you some old DVs.

KyleMP012 · #11 06-15-2018, 11:20 AM

Quote:

Original Post by Diesel3000

Just a word of advice and caution to anyone willing to be guinea pigs with DV face polishing:

USE THESE INSTRUCTIONS AT YOUR OWN RISK!!! PLEASE BE CAREFUL AND DON'T TRY THIS ON YOUR ONLY MEANS OF TRANSPORTATION!!! EVERYTHING BEING DISCUSSED HERE IS THEORETICAL AND EXPERIMENTAL!

If you do wish to try polishing your DV sealing faces, use common sense and follow the instructions below:

1: Make sure you have your DV oriented correctly. If it has a groove on the barrel, it should be pointing down, away from the plunger part of the DV.

2: Before you do anything to the DV, clean it in solvent, such as lacquer thinner to remove any varnish or contaminants.

3: Dip the entire DV in a thin oil such as sewing machine oil, or even WD-40 as a lubricant.

4: Use Cerium Oxide as your abrasive. It is extremely fine (finer than makeup powder) and is a very "soft" abrasive.

5: Use a battery operated drill and fasten the tip of the plunger part of the DV that the spring attaches to in your drill chuck.

6: Use a toothpick dipped in oil to transfer some of the cerium oxide to the beveled face of the DV. Try not to get it anywhere else. Keep applying until you have a coating of the cerium oxide on the face.

7: Insert the plunger into the barrel and press the two pieces together firmly and run the drill at medium speed for ~15 seconds.

8: Pull the parts apart and clean in your solvent. Inspect the faces and look for a polished appearance. If they need more polishing, repeat 3-7 above until you're satisfied with the final appearance.

9: Use a toothpick dipped in cerium oxide to clean up the entire beveled face of the plunger. I held the drill up and ran the tip of the toothpick back and forth over mine. This will help get any other oxides off and give you a fully polished sealing face.

10: Clean both halves of the DV in CLEAN solvent. Dry and repeat in a new pot of CLEAN solvent. Use a tooth brush or a Q-tip to really scrub everything perfectly clean.

11: Dip the DV in thin oil and reassemble to check fit. It should move freely without dragging. Press the DV halves together and twist. It should not feel "rough".

Keep in mind this process and all of the anecdotes attached to it are theoretical and experimental. If you screw up your IP or break your only car, you have yourself to blame. Not I, Pelican Parts, or anyone else is responsible for you or your engine. As the fine print always claims - "Your results may vary"

Gonna try this procedure from diesel 3000, worth a shot. If it doesnt work I'll replace the DV's. They are 41 bucks from this splendid sponsor, or about 34 from MB direct.

Diseasel300 · #12 06-15-2018, 11:27 AM

Just as a datapoint, I'm still running the DVs I polished when I wrote that up last year. The only time I ever have any nailing is when I have lousy fuel. I run straight pump diesel with BioBor JF as my only additive after I got diesel bug earlier this year from aforementioned crappy diesel.

KyleMP012 · #13 06-15-2018, 11:35 AM

That's great news to hear! The diesel out here in AZ is absolutely awful, I get better diesel from CA. Fortunately I found some Standyne at my local tractor supply so I'll give that a try. Wish we had B20 out here!

Mike D · #14 06-15-2018, 09:40 PM

Retail Map - Biodiesel.org

Select location (AZ) then "Show state".

The only thing I'd add to Diseasel300's method would be to use a drill press instead of a hand drill. It gives you better control and is easier on your arms.

KyleMP012 · #15 06-17-2018, 02:13 AM

Thanks for the link! On another completely separate note, I have no averaged 21 mpg on 3 thanks. Mostly highway and sub urban driving. Slightly un impressed to say the least. I know that the numbers MB came out with were high but I feel I'm way below that.