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Hello all,

I have a 560 SEC (`86) and it has a ticking noise from the driver's side valve cover. Gets quieter when warm, but sometimes you can still hear it a bit. Not sure if a video is needed, it's the classic metallic "tick tick tick ...". Sometimes it can be heard from the passenger side as well, but barely noticeable.

After doing some research and getting some info, I thought maybe I have mechanical (solid?) lifters that need adjustments. So I bought new valve cover gaskets, copper washers and oil tube kits, even though I know they have been changed around a year and a half ago. If I am doing work there, might as well change them again.

Well, after removing the valve cover gasket I found out that I might not have mechanical, but hydraulic lifters. I am still not 100% sure, still learning this stuff, but I am attaching a picture for confirmation.

Now... I am not sure what to do. I did not open the valve cover gasket for the driver side yet (where the noise comes from), but after I do, what do I check besides the general wear on the cam? Is there a way to actually check the lifters and rocker arms without some special tools?

I checked the space between the rocker arm and cam lobe (with cam lobe pointed up) for a few valves with a lash. Most of them didn't have any space between them (I think it's normal for hydraulic lifters?) but one had around 0.20 - 0.25mm ( 0.01 inches). Is that normal?

I am attaching some pictures of the passenger side, would appreciate some thoughts on the camshaft - it seems to have some areas where the lobes are not ideal.
 

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Good after noon Digital29,
Just a heads up when you are buttoning up you drivers side valve cover. Be sure you don't pinch the gasket on the drivers side, firewall end of the valve cover.

In my case i had a hard time getting this it seat tight and ended up putting a small amount of silicone in the corner to hold it in place while i was maneuvering it into position..

good luck
 

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Sounds like that one has collapsed a little maybe. Could be your noise. i wonder if it could be shimmed, or replacement would be better.
Be wary of aftermarket ones, I would venture if you go this route that good lower mileage used MB ones would be a better option.
 

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Discussion Starter #4 (Edited)
I assume you are talking about replacing the hydraulic lifter, right? In order to do this I also need the tool to compress the valve + the gauge to test if I need any shims, right?

Is there any way to test the lifters?

Also, I don't understand something. As far as I searched, a good deal of the m116 and m117 engines had solid lifters. Did something change in their production and they started using hydraulic lifters for them or was my info incorrect?
 

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Since the forum went to a new host platform searching for something sucks
Read this thread on the hydraulic compensators to get a good understanding of how to check them
Overhead cams engines are different in design and terminology of parts to pushrod engines- ie No lifter and no rocker arm
Hydraulic Compensator remains stationery screwed into the head. Follower arm is pushed down from above by the cam lobe to push the valve stem down.
The hockey puck (shim) sits on top of the valve stem to gap the required space and come in varying thicknesses to find the correct spec required using the no-go measuring tool.
 

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Photos #2 and #9 show some pretty significant pitting on the tip of the cam lobe. This may or may not cause you trouble in the future. I'd use engine oil with a high concentration of zinc, or an additive with ZDDP. Pitting on the sides of the lobe is less problematic, but not a good sign. This generally comes from lack of use i.e. long periods of sitting. Worse still is long periods of sitting punctuated by brief runs to "keep things loose."

Hydraulic lifters (or compensators, if you will,) get pumped up with engine oil. Over time, absent oil pressure, they leak down under pressure from the valve springs, so, any valve open when the engine stops will eventually develop clearance. As they wear, they leak down faster. This is the likely explanation for the clearance you measured on some of the valves. If the compensator cannot hold pressure at all (usually due to contamination of the check valve) You'll get a tick from that valve. If the tick goes away as the engine warms it's likely due to a lifter that leaks down then gets re-pressurized. One that doesn't go away probably won't hold pressure.

Another explanation for a constant tick is a worn cam lobe (refer to paragraph 1.) In this case, valve train components have worn beyond the limits the compensator can accommodate. Wear to this extent will likely continue to get worse, so simply adjusting the clearance will not solve the problem.
 

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Yes I have pitting on some lobes of mine. Such a shame, others on the same shaft look almost new. My car definitely sat, also extremely short journeys with an elderly guy to the shop at the end of the road.

Indie said to ignore it so I am. I got an awful tick, it was very bad. Turned out just to be a rocker arm which was very cheap and easy. Back to normal after that. (The slightest of ticks, only I notice it sometimes.)
 

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I had the tick tick sound and changed oil to MobilOne 15-50 (high zinc). No more ticking. It really worked!
 

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this was the sound of my worn cam lobe

 

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Would letting an engine sit/pits developing also apply to an engine out of the car in a workshop for close to a year?
 

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I recall a bit of wear one one cam lobe. The hydraulic lifter looked fine, but when we pulled the cam, the lifter flew out of there in pieces.

In time you might find a good same # cam in an area wrecking yard with good lobes and remove complete with all towers..
It's important to use some chicken, or insulated copper wire to make sure to keep all cam towers in the same orientation and position. You don't want them to get mixed up.
Cheers
 
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