1985 Mercedes TD 300 230,000 miles
When checking the valve clearance I noticed some slack in the timing chain.
How much slack should there be in the chain and what to look for in the tension rail wear.
Any help would be appreciated.
Thanks

Turbo OM617 => there shouldn't be slack in the chain - I assume you mean that you can rock the camshaft back and forth because there's slack in the chain?

If so check the tensioner.

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1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!

When the oil pressure is not acting on the tensioner you will see some slack in the chain. Slack is not wear. Wear, IMHO, can only be measured in degrees. You shouldn't see deep grooves in the rail and guides. If you do, it's replacement time...

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Did you just pass my 740 at 200 kmh in a 300SD?????

1978 300SD 'Phil' - 1,315,853 Miles And Counting - 1, 317,885 as of 12/27/2012 - 1,333,000 as of 05/10/2013, 1,337,850 as of July 15, 2013, 1,339,000 as of August 13, 2013



100,000 miles since June 2005 Overhaul - Sold January 25th, 2014 After 1,344,246 Miles & 20 Years of Ownership

My non turbo engine has an engine oil pressurised tensioner but I didn't think that system was used on a turbo OM617. So troutmaster4 do you have a turbo motor or not? In either case you shouldn't have a slack chain - perhaps we need a bit of clarification to help

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1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!

Yes, IIRC, both the 4 & 5 cylinder NA and 617 use an oil pressure fed tensoner with a locking ring to prevent relaxation of tension. However, you still see some 'slack' during valve adjustments...

__________________
Did you just pass my 740 at 200 kmh in a 300SD?????

1978 300SD 'Phil' - 1,315,853 Miles And Counting - 1, 317,885 as of 12/27/2012 - 1,333,000 as of 05/10/2013, 1,337,850 as of July 15, 2013, 1,339,000 as of August 13, 2013



100,000 miles since June 2005 Overhaul - Sold January 25th, 2014 After 1,344,246 Miles & 20 Years of Ownership

OK let's take a step back and ask what is meant by "slack"!!!!

__________________
1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!

I refer to 'slack' as any movement in the chain where you can 'rock' the cam gear and see deflection in the chain, such as when you remove the spring from the tensioner.

'Wear' in the chain I measure in degrees when checking cam timing. I realize this isn't a scientific explanation, but its how we approached them at the dealer on flat-rate pay...

__________________
Did you just pass my 740 at 200 kmh in a 300SD?????

1978 300SD 'Phil' - 1,315,853 Miles And Counting - 1, 317,885 as of 12/27/2012 - 1,333,000 as of 05/10/2013, 1,337,850 as of July 15, 2013, 1,339,000 as of August 13, 2013



100,000 miles since June 2005 Overhaul - Sold January 25th, 2014 After 1,344,246 Miles & 20 Years of Ownership

Thanks for all the input on the slack in timing chain question on my 85 300 TD wagon(turbo diesel).
The slack (I think) is considerable. Should I be able to wiggle the chain?
Is that what is causing the loose valve like sound from the engine? My 85 300 SD, 320 m miles has a similar sound though not as noticeable. Haven't had time to check if timing marks line up or how far they are off. The TD wagon (newly acquired) is a Calif. model (I think).
Local dealer couldn't tell by Vin is it was Calif.
What is a trap oxidizer? Is that the muffler looking under the car?
It needs new exhaust pipe, flex pipe is new.
Can "thing" be eliminated by having a local shop bend a pipe to fit?
Tried to keep this short and simple.
Any help is greatly appreciated. Thanks!

If you have the Trap Oxidizer it is on the front under the Manifolds and rather somewhat box shaped.
There is a so called Test Pipe that can be made of bought.
There is some threads on both in the DIY Section.
If you have the CAT in the Exhaust Pipe that is supposed to be the Fix; I think.
DIY Repair Links
http://www.peachparts.com/shopforum/forumdisplay.php?f=82
http://www.peachparts.com/Wikka/DoItYourSelf

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84 300D, 82 Volvo 244Gl Diesel

Thanks Diesel 911, you have given me lots of reading, will let you know how it goes.