On Om 601s how often do the Hydraluic valve elements need their adjustmen checked? - PeachParts Mercedes-Benz Forum

Diesel911 · #1 12-10-2007, 07:14 PM

I was looking at the Mercedes special tool site and saw a dial indacator set up 601 589 08 21 00; hydraulic valve elements; residual stroke guage for the residual stroke hydraulic valve clearance differential elements. Used on the OM 601 engines.
I assume they are talking about the hydraulic valve lifters and I am wondering how often they need to be checked?

#2 12-10-2007, 07:29 PM

Never unless there is a problem.

toomany MBZ · #3 12-11-2007, 06:57 AM

Quote:

Originally Posted by ForcedInduction

Never unless there is a problem.

Correct, hydraulic valves are self adjusting.
If you are that low of oil, you have other problems.

cornblatt · #4 12-11-2007, 12:12 PM

The tool you mentioned is used to measure the distance between the top surface of the cylinder head and the top of the hydraulic lifter. The factory service manual suggests that you measure this distance with the camshaft in place, and then again with the camshaft removed. The difference between the two measurements is the item of interest; it should be 0.25 to 1.6mm with new lifters, or 0.25 to 2.5mm with old ones.

I think this particular measurement is pointless. Unless your time is totally worthless to you, if you're going to all the trouble of removing & replacing the camshaft, then why not just replace the lifters while you're in there and be done with it. It's quicker to replace the lifters than to measure them as the manual suggests, and a set of lifters is probably cheaper than the special tool...

The service manual actually gives you several hours worth of tasks you can perform to check/repair/dismantle/rebuild the lifters. But they're only $16 or $17, so why spend all that time?

You never need to adjust or check them. They should last >100K miles and when they start to go, you'll hear a clinky or metallic tapping noise from the top of the engine. No noise --> leave them alone! Even if they do make a bit of noise intermittently, I've heard that this isn't really damaging to the engine (I replaced mine anyway because I didn't like the noise).

Diesel911 · #5 12-11-2007, 02:59 PM

Quote:

Originally Posted by cornblatt

The tool you mentioned is used to measure the distance between the top surface of the cylinder head and the top of the hydraulic lifter. The factory service manual suggests that you measure this distance with the camshaft in place, and then again with the camshaft removed. The difference between the two measurements is the item of interest; it should be 0.25 to 1.6mm with new lifters, or 0.25 to 2.5mm with old ones.

I think this particular measurement is pointless. Unless your time is totally worthless to you, if you're going to all the trouble of removing & replacing the camshaft, then why not just replace the lifters while you're in there and be done with it. It's quicker to replace the lifters than to measure them as the manual suggests, and a set of lifters is probably cheaper than the special tool...

The service manual actually gives you several hours worth of tasks you can perform to check/repair/dismantle/rebuild the lifters. But they're only $16 or $17, so why spend all that time?

You never need to adjust or check them. They should last >100K miles and when they start to go, you'll hear a clinky or metallic tapping noise from the top of the engine. No noise --> leave them alone! Even if they do make a bit of noise intermittently, I've heard that this isn't really damaging to the engine (I replaced mine anyway because I didn't like the noise).

Thanks for the information. I have also seen the tool (- the dial inidcator)recently on Ebay and was curious and went to the special tool site but. The site told me what it did but not why you would be doing it which led to me asking my question.
The opening bid was $5 with $10.50 shipping. No one bid on it!