High mileage 117 engine - PeachParts Mercedes-Benz Forum

pmckechnie · #1 05-26-2015, 10:03 AM

I would just like to now what is considered high mileage on a 117 engine. In other words, at what mileage do you consider a 117 done for. I know that the service it received governs how long it will last. I ask this question because my 84 500SEL just went over 300K. It runs great, will get 20+ mpg on the highway and 15+ in town, uses about 1 qt of oil in 1k to 1.5k. I just did valve guide seals and replaced the upper timing chain rails and pensioner and only had about 2 deg of stretch on the chain that has about 80 k on it. I haven't driven it much since the seals were replaced but it looks like the oil burning has improved.
What do you think about the 300K? Can I get another 100K or more out of it? My 91 2.5 diesel has 324K now and uses about 1 quart between changes. In other words, I never have to add oil.
Trivia, the 500 has 301K, the 124 2.5D has 324K and our 94 C1500 V6 has 298K. that comes out to 923K all together. 1,000,000 will be here before you know it.

Thanks

PaulM

pawoSD · #2 05-26-2015, 10:41 AM

The M117 is a beast, with proper oil changes and periodic chain/top end maintenance they can go for ages. I know of a person who had a 380SEL with the M116 with almost 800k on it....3 top end rebuilds...and a few timing chains. The bottom end is robust and can go practically forver. In normal driving these engines also don't have to work very hard to move the car.....I can drive all the way to work and back every day under 2k rpm easily if I wanted in my 420SEL...

My dad's old 420SEL had 311k on it when we discovered the timing chain guides were near-death, so we ended up retiring it as a top end rebuild+chain etc was more $$ than the car was worth at that point (some rust developing also) Its been sitting around as a parts car, and if you charge the battery the engine will still fire up fine.

JimFreeh · #3 05-26-2015, 01:09 PM

My 90 560SEL has 241k on it and has been fed a regular diet of Mobil 1.
No oil leaks or consumption.

Just swapped it to a good friend for my old 250C, so I'll have to see how it runs from afar from now on.....

Jim

Skippy · #4 05-27-2015, 07:48 AM

A few years ago I saw a 450SE for sale with over 270,000 on it. I didn't investigate further, as I had too many cars at the time.

pmckechnie · #5 05-27-2015, 08:36 AM

Thanks everyone, you have made me feel better about starting out on a long trip or something.

PaulM

pawoSD · #6 05-27-2015, 12:53 PM

With the gas engines I'd be more concerned with the condition of the alternator, belts....fuel pumps...fuel pump relay....ovp relay....distributor rotor/cap....cooling system....before a long trip, than the motor itself.

JimFreeh · #7 05-27-2015, 06:18 PM

Quote:

Originally Posted by pmckechnie

Thanks everyone, you have made me feel better about starting out on a long trip or something.

PaulM

My 1990 560SEL just left this morning for it's new home in Greenville, SC. about 500 miles.
We have no doubt it will make it just fine.....

I think durability is directly related to care.

Jim

Hit Man X · #8 05-27-2015, 10:51 PM

I swear one of the shop owners that posts here had a 420SEL go over 700k before a rod bearing finally had been worn out. Heads were off a few times from memory.

pawoSD · #9 05-28-2015, 08:45 AM

My M116 is still so tight that it doesn't leak a drop or lose a drop of oil between 5-6k mile changes....same comes out as goes in. And I don't drive it gently.

I did a lot of "age maintenance" on it last June, dismantled the entire intake, replaced ALL rubber hoses and pieces, new injectors, spark plugs, wires etc...has run flawlessly since. Idles at 550rpm nice and smooth.

That is probably the biggest poor-running culprit of M116 or M117 engines (and the M102/103) is dried out rubber pieces causing vac leaks everywhere...then they run terrible.

pmckechnie · #10 05-28-2015, 09:27 AM

Quote:

Originally Posted by pawoSD

With the gas engines I'd be more concerned with the condition of the alternator, belts....fuel pumps...fuel pump relay....ovp relay....distributor rotor/cap....cooling system....before a long trip, than the motor itself.

Thanks pawoSD,
I keep records of everything I do to the car in a spreadsheet with date and mileage, current mileage on the item, etc. I have a complete distributor with cap & rotor, ignition control unit, coil, fuel pump relay, ovp, belts, (all new or used/tested) and a few other various and assorted items in the trunk. I don't know about the fuel pump other than it has been replaced within the last 14 years and 80K miles. I know it has been changed but lost the records showing when, and my memory is not what it used to be.
I need to get a voltage regulator and will before we go very far. The current alternator is a 119 amp Bosch rebuilt with 54k so it should be OK for a while. I carry all this thinking that if I have it, I WON'T need it. If I don't have it I WILL need it.

Any other thoughts?

I still trust this car as much as any other car I have ever owned, including many new cars. It has had some problems, but has never let me down when I needed it except one time the battery was dead and I had to get a jump from a good Samaritan. I had warnings but ignored them. We were going through very troubled times and not thinking about cars. Our son had just had brain cancer surgery. After the jump, it got us and him home safely.

Thanks everyone for the comments.

PaulM

pawoSD · #11 05-28-2015, 04:15 PM

Fuel pumps should be good to go then, my original ones lasted to around 130k before they got real noisy and I replaced them preventatively.