83' 5 cyl diesel or 98' 6 cyl. diesel - PeachParts Mercedes-Benz Forum

#1 09-12-2007, 01:59 AM

I have a 1983 300cdt the engine is quite basic and easy to work on. I. however. am thinking of getting rid of it and getting a 1998 6 cyl mercedes diesel. I know that the 5 cyl. 1980-1985 motors were noted for thier bullet proof reliability. Is there any concerns about the 6 cyl motors of the 1998 diesels?

#2 09-12-2007, 03:35 AM

Glowplugs breaking off in the head are what comes to mind.

BioPOWER · #3 09-12-2007, 09:28 AM

Reliability? Some consider the 606 the most reliable/durable of the 60x series, and it certainly is the most powerful. Issues can include stuck glowplugs owing to the DOHC head (GP's are extra long), however, in actuality it isn't a rampant problem.

On the other hand, you will most likely encounter leaks from the engine bay fuel lines. Plenty of reading material here on that. Make sure you test drive it first, there are worlds of difference between the 606 and 617.

JimFreeh · #4 09-12-2007, 10:05 AM

The engine in a 98 W210 may look a bit familiar to a W124 diesel owner, but the is nothing remotely familiar about the rest of the car.

The computer/electrical/transmission level of sophistication is exponentially greater.

The W210 requires some significant investment in diagnostic tools, you're just not going to get very far with a meter and the shop manual.

Jim

JimFreeh · #5 09-12-2007, 10:16 AM

...But when they are bad, they are horrible!

I had a taste of this with my departed 400E, ain't the same as a W123!

Jim

JackG · #6 09-12-2007, 12:57 PM

My question would be, How long do you plan on owning it?
The 123 has already depreciated all it is going to, the 210
still has a way to go. Will the 210 even make it to a ripe old age
that a 123 will? Newer is always nicer in some aspects, But I like
dependablity and longevity alot more.

DieselAddict · #7 09-12-2007, 02:09 PM

I've had my W210 for over 2 years now and I've gotten by without any special diagnostic tools or specific manuals. Working on the engine is very similar to working on the older OM60x engines like the '87 300D that I used to have. I've read here that you can minimize the chance of breaking the glow plugs by removing them with the engine warm. Fuel leaks are common, but it's just rubber and it's a DIY job if you're at least somewhat mechanically inclined. Just don't expect the fuel system to be as bullet-proof as it is on the OM61x engines. There's a lot more rubber and plastic on the new one. But once you replace the affected parts you won't have to worry about it again for at least another few years. Lower control arm bushings tend to wear out and that typically shows up as a steering wheel shake around 55 mph. I would be most concerned about the front spring perches which tend to rust away and break off and the rust is not always apparent from the outside. Sometimes you have to temporarily peel off the undercoating to take a peek. Overall, the newer diesels are much more refined and luxurious than the older ones. They're just more sensitive and vulnerable in certain areas.

#8 09-12-2007, 05:35 PM

Thanks allot for the advice. I`m keeping my 300cd as I already replaced the fuel and injector lines with Viton lines. I run biodiesel and if you say the 98' has alot more rubber it would make me worry. I`ve already done much work on the 300cd so I know what it has and it needs. and it`s correct. I paid $2300 for it and a good 98" mercedes diesel is over $10K.