Hi Iwould think the engine was run with no oil,and or the oil took to long to hold pressure on the timming chain tensionor and it jump valve timing,I always fill the filter housing up with a fress qtof oil before starting the engine( tey also listen to the engind start before i do a service for a weak tensionor) thats the problem with fast oil changes they do not have the exsperianced techs.I would pull off the valve cover and see how far off the cam is maybe it just set back far enough not to do damadge and you can get away with some rails,chain and tensionor.joeym PS keep me posted are you any were near Long Island

During oil changes I have learned that filling the oil filter housing prior to engine crank is an excellent practice--I consider it a requirement of the oil change procedure, especially in the 420 SEL. If this is not done on my car, at the time of initial engine cranking/start there will be a definite few seconds before the oil is flowing through critical parts of the engine---not good!

Take joeym's advice! Maybe you will get lucky and not have to replace the engine. If luck is not with you and engine replacement is required, check out these websites:

noels.com (800.733.6635)
mercedesengines.net (800.622.6867)

Welcome to the S Class Forum and thank you for your participaton!

Well, I appreciate the comments so far on the major problems I am having after having made the mistake of taking a luxury car to Jiffy Lube. I'm taking it to the dealership from now on, that is if I can afford to have this paid for out of pocket.

Joey - I am in L.A. This ocurred at the Jiffy Lube #706 at 7020 Sunset Blvd. at Santa Monica Blvd. I'm looking at the invoice they gave me, which I assume they filled out *after* the service, and it says "oil level on arrival - no reading," "possible engine oil leak," and "unusual engine noise".

First of all, there has never been any problem with oil leaking out of this car. The car does require me to add oil every so often, but I assume this is normal with an engine of this caliber. There has never been any oil spills on the pavement under my car outside of my home. I would notice something like this. Also, the "unusual engine noise" comment is a complete fabrication because neither myself or my mechanic noticed any such thing about the car. I drove it every day and I would have certainly heard an unusual noise. The mechanic worked on the transmission for a few days, test driving the car etc, and didn't comment about any noise. Does it seem to anyone else like perhaps these technicians are trying to buffer their mistake on their service invoice by adding these remarks?

I'd think small claims is perfect for this. Try and get the technician served as well - it might cost you an extra $60 or so +/-. There is NO WAY a Jiffy Lube tech will lie on the stand for that lousy job...

I think your drivers side chain guide broke causing the chain to jump a few teeth bending your valves. Common problem with old chain quides and excessive chain stretch. Jiffy Lube was co-incidental.

Hi Iam not to sure about co-incidental,the veh was running when it went in for service ,if the tech heard a noise and it was enough to note it down Why not call the veh owner before you do any work.joeym

He took it to Jiffy Lube. Typically, the owner waits in the waiting room while the 'techs' 'work' on the car.

I am intrigued by the advice to pre-fill the oil filter during oil changes. Although I've done this on American cars with a screw on filter, (and installing in an upright position) I am having trouble seeing how it is done on both my vehicles, 97 C280 & 92 300SE, which have cartridge filters that attach to the screw-on top. In order to fill, the top must be off and then the filter is not seated which would allow the new oil to flush any residual oil in the filter housing back into the engine. The residual is oil/contaminants that have not yet been trapped in the filter material. Filling with the filter in place would make it harder to get the top seated properly. Am I missing something?
Tim

Hi No you are not missing something,your veh will drain right down,it was the upright fix oil filter canister and lower screw on canister we were taking about,ex: 116 117 119 MOTORS.JOEYM

Today I just received this letter from Pepper Tree, Inc. who apparently handles all Jiffy Lube's legal claims. Regarding this engine issue with my 420SEL:

"...only the right bank of cylinders has zero compression while the left bank is normal. Since this is a dual cam engine, it is obvious that one camshaft is not rotating which is due either to a bad chain or drive gear which is located deep inside the engine and it would have to be torn apart to discover what is broken. In any case, there is nothing in our procedure that could cause this problem. At this amount of miles, this is not an unusual occurrence."

They go on to cite the note on my invoice regarding the oil level and unusual engine noise. The letter then states that it was "obvious I had a failing engine and it simply chose now to break."

Earlier this afternoon, I filed in Small Claims Court for the maximum amount allowed under California law ($5,000) for the repair, diagnostics, storage, car rental, and inconvenience.

Anybody have any thoughts on their letter? The repair shop is saying this job requires timing chain, tensioner, rails, valves, and head work.

Just curious, what's the latest on this?

Ok, well the latest on my engine is this:

I took the car to the Mercedes dealership of Beverly Hills for a 2nd opinion diagnostic and they told me the exact same thing as the first mechanic, but in order for them to open up the engine and determine exactly what happened within the engine to make the chain jump would require additional labor in the amount of $3,000+. They also gave me a quote for a Mercedes factory refurbished engine of the same size...$29,500. Obviously, the car even in *excellent* condition is not going to fetch more than around a 1/4 of that amount if I were to sell it.

Therefore, I have a date in L.A. Small Claims Court with Jiffy Lube in which I am asking for the maximum amount I am allowed - $5,000. I am remaining optimistic for the time being because the problem occurred while the keys to the vehicle were in their hands. I sincerely believe that it was not a coincidence as they claim. I feel that if a problem this significant occurs while being serviced by a business, they should have sufficient coverage to back up their work if something goes wrong. Even if the problem is not directly related to the procedure being performed, and some sort of damage occurs to the vehicle while it is under their roof, they should have coverage for that. It just seems like responsible business.

Also, the first mechanic looked at the letter of denial from Pepper Tree/Jiffy Lube and stated that he disagrees with their assessment. The camshaft they say is not rotating IS rotating.

I have also proceeded to file a complaint with the Bureau of Automotive Repairs for the State of California.

All I want is for the engine to be restored to the driveable condition it was in at the time I drove the car into their shop. Most likely this will involve rebuilding the top half of the engine at least.

I value any comments or suggestions, for they may help me get the engine repaired!

Sincerely,

Justin Champion
'91 420SEL

Just curious, (didn't notice, but may have missed in a previous past) was the timing chaing/tensioner/rails changed @100K?? I let everyone I come acroos w/ an M116/M117 every mile over 100K is borrowed time.

Some listen, some don't..I've bought more then one nice car w/ a bad motor that way.

Best of luck in Court!

Jonathan

The car had 142k when I purchased it. I do not know if it was changed at 100k.

As far as the court case goes, the judge ruled in favor of Jiffy Lube. This was due to my burden of unquestionable proof that the damages ocurred as a direct result of the service. I was only able to prove that it ocurred in their hands but their argument was that it was coincidental.

Therefore, I have to foot the bill for this out of pocket. My mechanic says he can do the rails, tensioner, timing chain, valves, and head for around $3,200 - 3,500. My other option is selling the car as a Mechanic's Special here in Los Angeles at a tremendous loss. You win some, you lose some...

Hi Justin Iam suprised he was able to give you an estimate,before the heads are off.I would have him pay attention to the piston deck highth as you could have a short rod.joeym

I have owned a 1985 380SE and now own a 1991 420SEL and they had problems with the 1981 to 1983 engines that were single row timing chains. Mercedes learned and upgraded later models to a double row chain. The models I had used the double chain system. However, the guides are "plastic" and if the chain gets worn and stretches, about 100K miles and it starts slapping, the plastic guide can break and go BETWEEN the cam sprocket and chain. When this happens the chain is forced up and the valve train goes out of time and the pistons impact thie valves bending them. Usually the repair is to pull the one head on the damaged side, and repair the valves and put in new chains and guides. Also the valve cover must usually be patched since the chain will punch a hole in it. This is a $3300 fix. Preventatively replacing the chain and guides is a $1200 job, take your choice.

How do you know when to change the timing chain? When upon startup you hear an initial rattle sound from the chain go and have the tinming chain and guides replaced. This sound will not be there and then within a few weeks it will be there. If you want to be conservative change the chain and guides at 100k miles and forget it.

My guess is the car you bought did not have the chain and guide job done and it was lucky to last to 140k miles. When the oil was changed the tensioner was a bit slow to pressurize and the chain slapped the guide and thats all she wrote.

Don't feel bad its a poor engine design in my opinion that they tried to fix and still didn't make the grade with the double chain. Spend the $3300 if the car is sound and enjoy it. They are a dream when they are running right.