1985 500 SEC Rocker Arm Fell Off - PeachParts Mercedes-Benz Forum

jzerres · #1 12-21-2007, 09:13 AM

Hi I have a beautiful 500 SEC and it ran perfectly, no smoke, all power, and ran like a dream. I let my wife drive it and when she did she said it stalled on her. I came to her rescue and saw the the valve cover on the driver side was cracked. I had it towed to a car repair center and they took off the valve cover and said I needed a new engine , as they drooled over it. I knew that I did not need a new engine. I saw that the rocker arm had fallen off, and looked at the guides to the timing chain, and everything looked very clean and on. The springs where intact, the valves looked straight. How do I place on the rocker arm?.

whunter · #2 12-21-2007, 11:28 PM

Quote:

Originally Posted by jzerres

Hi I have a beautiful 500 SEC and it ran perfectly, no smoke, all power, and ran like a dream. I let my wife drive it and when she did she said it stalled on her. I came to her rescue and saw the the valve cover on the driver side was cracked. I had it towed to a car repair center and they took off the valve cover and said I needed a new engine , as they drooled over it. I knew that I did not need a new engine. I saw that the rocker arm had fallen off, and looked at the guides to the timing chain, and everything looked very clean and on. The springs where intact, the valves looked straight. How do I place on the rocker arm?.

Possibly caused by failed Hydraulic Ball Stud or damaged rocker.

PART NUMBER SEARCH RESULTS WITH PRICES
Vehicle 1985 Mercedes Benz 500SEC
Part: Ball Stud
Note: Hydraulic
A4180-15405 Ball Stud Febi IN STOCK

A4180-15405 Ball Stud IN STOCK

Have a great day.

Chas H · #3 12-21-2007, 11:36 PM

It can also by caused by an out of time timing chain. One bad ball stud shouldn't cause the engine to stop.

whunter · #4 12-21-2007, 11:46 PM

Quote:

Originally Posted by Chas H

It can also by caused by an out of time timing chain. One bad ball stud shouldn't cause the engine to stop.

Check base timing marks...

jzerres · #5 12-22-2007, 08:51 AM

I got the email with the information and I am every so thankful for you and everyone here helping me out. I love this car. Even when it sits as a lawn orniment it looks great. This is the first time it had to spend some time outside. It calls me, fix me, fix me. I think now that I have been through the forums , that the oil that was used may be a part of the problem. I will as this forum suggest use Mobil. Kind od hard to get a good mechanic as I live in the mountains and farm land of NJ. I had taken it to a local shop and they did an oil change and placed on a new complete exhaust system. Gave me a two year sticker, but when I had it taken to them to look at, they where and I mean this drooling over the car, there are drool marks on it. I knew it did not need a new engine, I have in the past made a 1991 LX 5.0 Mustang not so street legal. When I moved from SC to NJ it would not pass inspection, due to no converters, had to trade it in for a Jeep cherokee with a 4.0 4 wheel drive as it does snow here. But I love this Mercedes 500 SEC. So clean underneath that you can really eat off of it. Even if this does not repair it, and needs other work done, I want this car to be healthy. And the fact that you all are helping me makes me feel so good about it, that I feel its my obligation to show you the work.

Joe

jzerres · #6 12-22-2007, 02:10 PM

Hi guys, upon further inspection of the timing chain area I found pieces of the timing chain guides. I am not happy, but I am glad that I saw this. Will look into having that done and new timing chain and god knows what else. I love my car so much that I hate it. But I will do what nneds to be done, either by me or a professional. Thanks and have a good holiday.

Joe

Tomguy · #7 12-22-2007, 04:23 PM

If you found pieces of timing chain guide rails...
And your rocker came off...

Chances are (unfortunately) that a failed timing chain guide ($20 plastic part) caused your engine failure. The timing chain jumps time, and the valve smashes against the piston (which would result in the rocker arm being thrown off). Usually you need new valves and guides for an entire side of the engine, often it damages the valve seats and pistons as well. At this point what you need to do is verify whether or not you can turn the engine by hand. Don't attempt to use the starter, it'll spin the engine too fast and cause certain damage if the chain has jumped time but no serious valve/piston meeting has occurred yet.

jzerres · #8 12-22-2007, 04:59 PM

You know and I know that I am going to have to do a complete rebuild. What I saw from another forum was the guides from a picture, then I looked at mine, and I almost cried. Well, I do love/hate my car. S.Jersey gave me a good price on a complete rebuild. 4500. I will go this route since I can not do it myself. Nice for you to look at the posting and comment on it. I to like to share information to help others. Just think, new rebuilt engine, 3 year warranty. Hmm can't wait.

CamelotShadow · #9 12-23-2007, 12:27 AM

I know how you feel
They call to you
Mine was so happy
Drove it 2 days in a row
It was in its glory
I felt good about getting it out too
I think it thinks it's christmas
They are such great cars

I too have worries about the timing chain
its not good to push those plastic parts past there useful lifetime.

Good Luck getting yours back on the road

t walgamuth · #10 12-23-2007, 07:58 AM

The bottom end is almost certainly in excellent condition. Personally I would not pay for a full rebuild when the damage is on one side.

My $.02.

Tom W

whunter · #11 12-23-2007, 10:49 AM

Quote:

Originally Posted by t walgamuth

The bottom end is almost certainly in excellent condition. Personally I would not pay for a full rebuild when the damage is on one side.

My $.02.

Tom W

Guides, timing chain, replace damaged valves + cylinder head service is all you should need.

jzerres · #12 12-24-2007, 08:12 AM

Quote:

Originally Posted by whunter

Guides, timing chain, replace damaged valves + cylinder head service is all you should need.

You know, that would be just fine, but I would worry about the rest of the engine. Having everything rebuilt would make my mind at ease. Lets say I get the top end rebuilt, then I have no oil pressure, cause the bearings go, if I do a complete rebuild for the great price quoted by this shop in SJersey , new I feel is great a 3 year warranty even better. Basically a new car. New motor mounts and tranny mounts, springs would not be a bad idea, as well as shocks. I figure if I put enough money itnto it now, I will worry less later. But then again its a Mercedes.

pastmaster · #13 12-24-2007, 10:00 PM

That was quite an impact to knock off the rocker arm!

I would wait and look around for an engine that will compliment the condition of your 500's. There is an engine sitting in the corner of a shop, that has been re-built or a 500, like yours, was totaled and the engine wasn't touched. Good luck with it.

jzerres · #14 12-26-2007, 05:53 PM

http://www.headmasterinc.com/engines.html

The above shop is the one that quoted me the price on rebuilding. Talked to the owners son, and they do Mercedes well.

david s poole · #15 12-27-2007, 10:26 AM

if you're going to rebuild top end make sure that all 36 head bolt holes are helicoiled.with steel bolts into aluminum threads it is not a matter of if the aluminum threads will fail BUT WHEN.