OM602 Injection Pump Reseal? - PeachParts Mercedes-Benz Forum

JamesDean · #1 03-26-2014, 08:52 AM

Hey everyone,

I had my 300D up at the shop the other day for some minor things. I had them identify some oil leaks for me. One of them was from the oil level sender. I can handle that. They said the majority of the leaks were coming from the injection pump. The leaks were not bad or anything but they were present.

At the moment I run 8,000 mile oil change interval with Rotella T6. I don't add any oil in between changes so whatever is leaking out is not much.

I put about 30K miles on per year so I'll eventually have to deal with this leaky IP. They said that this isn't something that they would reseal and likely not me either. They said to send it out to a diesel shop.

Does any one have any thoughts on this? Recommendation? Cost projections?

Thanks!

shertex · #2 03-26-2014, 08:57 AM

What typically leak are the gasket and and the o-ring at the bottom of the IP. IIRC it's about 5 hours labor to replace those.

MBZ123 · #3 03-26-2014, 08:44 PM

The more common leaks are from the DV holders. O-rings fail and fuel floweth past. I'm dealing with this currently. Waiting on the tool to arrive.

OP - If you look at the IP at idle (cold or at temp) does it appear wet? How about after a lengthy trip? Easy way to determine source would be a power wash then a short spirited drive. If the entire pump is wet, most likely it is the DV's. Couldl also be stop lever. If only dripping from beneath, then bottom seal is suspect. There's a DIY or two around here somewheres for that.

My issue started off with visable flow of fuel from DV's dripping to the ground, but has nearly cured itself to just getting damp anymore. With just driving. The performance hit was noticeable, too, at first. To the tune of one or two mpg. Insane. Not so much anymore.

To do the reseal, you'll need the o-rings as well as the copper seals. I believe DeiselMeken has a youtube on it. Check it out.

Shertex - Did you ever post an update after the 300D HG change by your indy? Would like to know what all was involved and how its running since.

MBZ123

shertex · #4 03-26-2014, 08:59 PM

Quote:

Originally Posted by MBZ123

The more common leaks are from the DV holders. O-rings fail and fuel floweth past. I'm dealing with this currently. Waiting on the tool to arrive.

OP - If you look at the IP at idle (cold or at temp) does it appear wet? How about after a lengthy trip? Easy way to determine source would be a power wash then a short spirited drive. If the entire pump is wet, most likely it is the DV's. Couldl also be stop lever. If only dripping from beneath, then bottom seal is suspect. There's a DIY or two around here somewheres for that.

My issue started off with visable flow of fuel from DV's dripping to the ground, but has nearly cured itself to just getting damp anymore. With just driving. The performance hit was noticeable, too, at first. To the tune of one or two mpg. Insane. Not so much anymore.

To do the reseal, you'll need the o-rings as well as the copper seals. I believe DeiselMeken has a youtube on it. Check it out.

Shertex - Did you ever post an update after the 300D HG change by your indy? Would like to know what all was involved and how its running since.

MBZ123

Yes, the DV seals are a common fuel leak. All I've seen oil wise is from the bottom of the IP. Oh, and also at the shut-off valve, which is an easy fix.

300D head gasket repair was a success....although lots of frustrating careless mistakes that had to be rectified. A competent mechanic who employs goons is not a good arrangement. But 10k miles later and all is good.

shertex · #5 03-26-2014, 09:08 PM

So Kris, where on the IP exactly are the leaks coming from?

JamesDean · #6 03-26-2014, 09:09 PM

No fuel leaks that I have seen. Dry in that regard. Oil leaks are very slow. Maybe 1 Oz over 8K. MAYBE.

Honestly I'm not 100% sure, I didn't look at it myself. I didnt see anything on top of it or in the area visible from the hood. So I would assume underneath..somewhere. It not a horrible leak by any means. I havent had to add any oil to the engine in any of my last oil changes (8K intervals)

Diesel911 · #7 03-27-2014, 12:15 AM

Quote:

Originally Posted by shertex

So Kris, where on the IP exactly are the leaks coming from?

X2 and what is leaking?

Diesel911 · #8 03-27-2014, 12:20 AM

Quote:

Originally Posted by JamesDean

No fuel leaks that I have seen. Dry in that regard. Oil leaks are very slow. Maybe 1 Oz over 8K. MAYBE.

Honestly I'm not 100% sure, I didn't look at it myself. I didnt see anything on top of it or in the area visible from the hood. So I would assume underneath..somewhere. It not a horrible leak by any means. I havent had to add any oil to the engine in any of my last oil changes (8K intervals)

People have had Lube Oil Leaks at ther various shafts that come out of the Fuel Injection Pump, there is that Pan on the Bottom and then there is the (Old Diesels) Bock to Pump Gasket (Newer Disels) the Bolck to Pump O-ring.
If it is an M-pump there is a Rubber Gasket on the Side Cover and all Fuel Injection Pumps have a Gasket at the Fuel Supply/Lift Pump.

Rare Governor to Fuel Injection Pump Housing Gasket leak.

Not worth the $$$ for a tiny leak until you can determine where it is leaking.

JamesDean · #9 03-27-2014, 08:38 AM

I agree I'm not going to do anything for such a tiny leak.

This thread was mainly to get recommendations on someplace to send the IP for resealing.

My shop said that this wasn't something that they would do and didn't have a recommendation as they don't see too many of these cars anymore and haven't needed to do anything like this in quite some time.

Here are some pics of the pump, they were taken when I bought the car in 2012:

http://i.imgur.com/HCFk0.jpg

http://i.imgur.com/5SwoQ.jpg

http://i.imgur.com/rpR1z.jpg

As far as pinpointing the leak I'll have to look and see what I can see.

pwogaman · #10 03-28-2014, 07:06 AM

I've gotten a bit of oil leaking out from the manual cut-off lever. The o-ring wears down.

Diesel911 · #11 03-28-2014, 01:44 PM

Quote:

Originally Posted by JamesDean

I agree I'm not going to do anything for such a tiny leak.

This thread was mainly to get recommendations on someplace to send the IP for resealing.

My shop said that this wasn't something that they would do and didn't have a recommendation as they don't see too many of these cars anymore and haven't needed to do anything like this in quite some time.

Here are some pics of the pump, they were taken when I bought the car in 2012:

http://i.imgur.com/HCFk0.jpg

http://i.imgur.com/5SwoQ.jpg

http://i.imgur.com/rpR1z.jpg

As far as pinpointing the leak I'll have to look and see what I can see.

I believe all of the items Imentioned have been resealed by the Owners.
However, I think the IP would need to come off.

If it is that lever in the Pic that is leaking it useas a sort of square X crossectiond O-ring (see the pic). Sometimes a round cross section one will work sometimes not.

You need to be careful that you mark the position of the Lever so it goes back on where it came off and do not push the Shafe inside trying to get the old O-ring out or installing the new one.

Between the Lever and the Housing there is a Bushing that has a Hes Head on it. On the other Bosch Fuel Injection Pumps I have worked on that Bushing does not screw into the Housing but actually has a "C" Clip on the inside retaining it. That Busing also has an O-ring on it and is is usually a round crossectioned one.

If it is the Cover Gasket that is leaking I believe Mercedes sells them as a single item.

For both Cover Gasket and O-ring Bosch Fuel Injection Shops will have them.

MBZ123 · #12 03-29-2014, 02:01 AM

Judging from the pics, most likely from the stop lever. None of your images show the mating location between pump/block so that's another possibility. Def not the dv's. I suggested so because the fuel, being a decent solvent, will look like oil on the ground.

You said pics were snapped when you took possession of the vehicle, correct? Makes sense as it seems that area (poss. entire engine bay) was just washed. Taking a couple pics now would show exactly where any leaks may be.

I agree with what's been said already about not being an issue. Not sure how you measure being low one ounce, but over 8k miles is hardly cause for concern. Sure you didn't mean a quart every 3k? Could be that it is only the sender leaking. Reseal and enjoy your car.

One peculiar detail tho, appears the side plate, stop lever arm and bottom plate are painted black. Anyone else seen this before? Wonder why...

MBZ123

shertex · #13 03-29-2014, 08:52 AM

I would concur that it looks like it's the stop lever. Here's a good write-up. PeachPartsWiki: Injection Pump Stop Lever Oil Leak Fix

funola · #14 03-29-2014, 10:52 AM

Diesel is clear and thin, flows and wicks too fast to pinpoint its origin, however it is clearly visible against toilet paper, no matter how small the amount. Have as many folded up patches of toilet paper ready and start from the top of the IP (injector nuts) and blot your way down till you find the exact leak spot. If the toilet paper is wet, fix that leak before going down further. Use long nose pliers, tweezers, make special tools for hard to reach areas if you have to.

I have always been able to pinpoint exact leak spots by this method and not by trial and error replacement of seals.

shertex · #15 03-29-2014, 11:13 AM

Quote:

Originally Posted by funola

Diesel is clear and thin, flows and wicks too fast to pinpoint its origin, however it is clearly visible against toilet paper, no matter how small the amount. Have as many folded up patches of toilet paper ready and start from the top of the IP (injector nuts) and blot your way down till you find the exact leak spot. If the toilet paper is wet, fix that leak before going down further. Use long nose pliers, tweezers, make special tools for hard to reach areas if you have to.

I have always been able to pinpoint exact leak spots by this method and not by trial and error replacement of seals.

Genius, that be.