E420 Oil Tubes/Power Loss - PeachParts Mercedes-Benz Forum

#1 06-04-2003, 09:40 PM

I recently posted about a ticking noise that, thanks to the remarkable knowledge on this forum, is most likely one or more broken oil tubes. I needed the car for the past few days and finally got it to my mechanic today.

For the past two days, I have noticed a definite power loss when the engine completely warms up. In the morning, with a cold engine, it has all the torque I normally expect, but as the engine warms up throughout the day, low-end torque seems to disappear. The engine still has plenty of power once it revs up above 3k.

I guess I'll find out next week if this is related to the oil tubes and the noisy lifter, but I was wondering if anyone has any input. I was thinking maybe the lowered oil pressure is affecting the variable valve timing and when the engine is cold it has enough oil pressure. Does anyone know if low oil pressure could cause a power loss like this?

P.S. the '97 E420 doesn't have an oil pressure guage.

DR.DIESEL · #2 06-04-2003, 09:51 PM

You betcha. The wide open oil loss from a missing oiler-tube end plug drops the engine oil pressure to 1 bar or less when hot.
This causes adverse effects on the cam timers which are opereated by oil pressure. The knock sensors also pick up the racket and start to goof with timing.
I recommend people do not drive their cars in this condition for extended periods, because I have seen damage to the cams and lifter tappets result.
DR.D

#3 06-04-2003, 10:08 PM

FANTASTIC NEWS!!! Great. I thought once I got the oil tubes fixed I'd be right back in with another fiasco. Luckily, I have put less than 50 miles on the car since it started lagging like that. Thanks for the info.

BTW the car is under a 1-year/15K warranty with an independent used-car warranty called CARS. If anyone has any info about their reputation or past problems, I'd appreciate it. The mechanic says he'll be talking with them once he opens up the valve covers.

Thanks again, now I'll be able to sleep at night for the next week that I'm out of town!!

#4 06-11-2003, 10:20 AM

Just an update on the situation. I just got off the phone with my tech and he said SEVEN count 'em SEVEN oil tubes were blown out! I doubted him and he said he'd save them for me to look at. I asked him about the power loss and he said that with all of those missing he's surprised it didn't lag even worse. Apparently you're right Dr. Diesel, the lack of oil pressure has a significant effect on the valve timing, etc. Unfortunately I'm across the country right now so I haven't had a chance to drive it yet. I'll report back soon with that.

The tab you ask? Almost $1100. Yikes. I know, it's worth every penny, but cripes! The good news is, I think I found a great mechanic. Without calling and pestering me for approval, he went ahead and replaced all (16?) tubes and put in new upper guide rails because he said they were looking brittle. He also replaced some other tubing/parts he said looked brittle. What's more I asked him to flush the cooling system, but he came back and said he didn't do it because the coolant looked fresh and must have just been changed. I'm impressed. BTW, that $1100 included a $220 transmission fluid/filter change I had asked for. I think it was a fair price for good work.

A word about the warranty. The tech said they were the shadiest warranty company he's ever dealt with. They only pay $45.00/hr. shop rate, take it or leave it! With the $100 deductible they ended up only covering $350 of the +$800 tab for the oil tubes! If anyone knows about CARS warranties or has had a similar experience, let me know. So far I am totally unimpressed and I'm thinking about having my lawyer write a nasty letter.

So since I've bought the car I've already put close to 2 g's into it making it perfect. The funny thing is, it doesn't really bother me at all! It's a BENZ and it's MINE!

-fad · #5 06-11-2003, 10:38 AM

...with such low miles and a only 6 years old...wondering why the oil tubes would have failed?

anyone know?

tks-fad

#6 06-11-2003, 10:44 AM

was wondering the same thing. Hopefully it's not from rampant abuse by a 16 y/o leadfoot! The car's never been in a wreck, has all of the maintenance pages signed off, and I am only the third owner. Anyone know what could cause so many of these tubes to fail before 60K?

JimF · #7 06-11-2003, 11:59 AM

so many tubes going 'open'. But if you look at the way the tubes are fabed, it's just a matter of time till they fail.

Although, my tech, whose been a Mercedes man for 30 yrs+, has never seen an open tube. In fact my car was the first he had seen. After mine, he had one other. Interesting??? I've had three (3) tubes fail: two on the right, one on the left.

The tubes in '92s (500SL) are metal with spring loaded end cap using a 'beebe'. Much better quality.

Where were open tubes? What side and cyclinders?

#8 06-11-2003, 12:48 PM

Shoot Jim, I didn't know you were in San Diego. I would have just driven it down there and used your tools!! Just kidding. I have read some of your other posts and it sounds like you've got a full-on shop going at your house.

There were broken oil tubes on both sides, but since I didn't do the work I don't know which ones specifically. One interesting thing, though. Right before I brought it in the tapping noise went from a slow 1/4 second tempo to a double-time tapping. This obviously was yet another lifter running dry probably from the opposite side. As I said before, the tech said he found SEVEN blown caps and I'm pretty sure there were some from both sides.

One question, is it necessary to pull the oil pan to retrieve the pieces from these oil tubes, or do they sit in the valve cover where they can be easily retrieved? I'm a little concerned that now I have plastic pieces floating around in my oil system.

JimF · #9 06-11-2003, 02:02 PM

. . . where did those little caps go? . . . but I never found any of mine. Probably went into the filter? or out the oil drain. I wouldn't worry about them. Famous last words, eh???

placo1 · #10 06-11-2003, 09:00 PM

Jim,

What were the symptoms that made you check the oil tubes? I get intermittent lifter noise at startup and occassionally until the car is completely warmed up.

TIA!

#11 06-11-2003, 09:19 PM

Famous last words indeed! The only thing that concerns me is that I think I read on a thread somewhere about a guy whose cap got sucked up by the oil pump and shot out the side of the pump housing. Yikes. That would be bad.

As for your previous concern about metal on metal and the tappets running dry, you're right. My mechanic was actually expecting to replace either some worn cams or at least some lifters, but he said there was no damage at all. Got lucky there.

As for SEVEN tubes blowing out, I talked to my tech again today and he said that the previous owner probably just let the first one go or didn't hear it and then the other ones went one at a time--probably over the course of a year or two.

Can't wait to take it for a drive on Saturday.

#12 06-11-2003, 09:35 PM

Oh yeah, here's a breakdown as I remember it over the phone:

Oil tubes (16 of them): 16 x $18.00=$288.00
Gaskets, breather tube, etc: $35.00
New guide rails: $50.00 or so
Labor: 4hrs. x $75.00=$300.00

$673.00 plus tax for the tubes and guide rails.

Meza · #13 06-11-2003, 10:28 PM

I have the same symptoms described. when cold after startup it runs great. Once it warms up, it has no power at low end and drives great at around 3000 rpm. How do these things look like if I have them on my 190e?

placo1 · #14 06-11-2003, 10:58 PM

Wow the oil tubes are much more expensive on the E420.

They cost $1.80ea on the M119 although you need 32 of them.

#15 06-11-2003, 11:32 PM

I'm going to start calling this forum 'the crackpipe' because I'm totally addicted. I find myself on here constantly.

Meza: I'm not much of an expert, so I don't know about the 2.6L engine. I've only heard about it on the M119 (4.2L V8). Interestingly, JimF and I have been emailing back and forth and he does not think that my power loss was related to the oil pressure at all. What I'm hearing from Jim is that he thinks the power loss was due to the dried out, collapsed tappets failing to open the valves fully. Maybe you have a valve or a lifter problem. Out of curiosity, does your engine have variable valve timing?

Placo: I'm pretty sure my E420 has the old-school M119, but I'm double sure my tech told me there are only two tubes per cylinder. I guess one tube feeds two valves. Maybe the 119 you're talking about is a different version of the same block.

As for the price per tube, I could be wrong, he read everything to me very quickly over the phone. I'll double check and update on Saturday when I get the actual paperwork. He did say that the new tubes are aluminum and are much higher quality. Maybe the price you are talking about is for ones like the original plastic tubes.

Someone please check me in to Betty Ford, I'm addicted to this forum.