How m117 should sound?

[Em86]

https://youtu.be/swFXzo4Qmj4

This is my 1975 450SE. Does it sound normal for m117? I havent heard any other v8 MB so I cant compare.

I am currently thinking of renewing timing chain and camshaft oil tube holders. I think the engine does not sound as smooth as it should be. The rattling noise come from inside the valve cover. The car has only 199 000km but its old.

Any opinions are welcome!

[UTn_boy]

Judging from certain things I see, you have a D-Jetronic M-117.  This tells me that you have valves that have to have their lash set manually.  Th rattling you hear is likely because the car hasn't been serviced regularly and/or correctly.  Valve lash must be checked/set every 15,000 miles. 

Regarding your mileage, 199,000 km a is approximately 123,000 miles.  Rule of thumb for timing chain, upper chain rails, and chain tensioner is to renew them at 100,000 intervals.  If you'rs hasn't been done, then it's past due, and possibly a ticking time bomb.  Get it done as soon as possible, along with the camshaft oiler tube bushings you mentioned. 

Past the noisy valve train, everything sounded normal to me. 

[daantjie]

The M117 sounds about 80% as good as a 6.9

[ptashek]

Sounds like the timing chain is long overdue for servicing.

For comparison, here's my 1979 K-Jet M117.986, pre-restoration at ~118kkm (70k mls):

http://www.dropbox.com/s/yya8orhzx985g4i/merc_v8_idle.mp4?dl=1

[13B]

Here's what mine sounded like after doing the chain, sliders, tensioner, sprockets, oilers, and setting the lash for the first time in 20 years:

https://www.youtube.com/watch?v=_8ugcl0oyak

Ian.

[Em86]

wow! My M117 definetly needs some tuning and valve adjusting.

I dont have the tools to make it on my own. I believe a good, experienced Mercedes mechanic can do the job. Even for car thats from 1970´s

The problem with the D-jet engine is that there are not many mechanic that are familiar with the electronic fuel system.

[marku]

Definitely a priority to replace the timing chain mine has big grooves down the insides of the heads from a failure. Something that happened with a previous owner. When I got it the chain had been replaced but had obviously stretched so I replaced it and also all the guides.Top ones are OK but the others are difficult. It is also very difficult set the valve clearances as the adjustment is very tight. I found it easier in the end to remove the rocker make the adjustment refit the rocker and test the clearance and keep on doing it until correct. A real pain but I was risking rounding off the adjuster otherwise. The only way for the D-jet is to learn to do it yourself. Specialists are few. Bosch have reissued their D-jet manual which is well worth having.