As I've read up on the proper procedure for changing coolant (it's certainly clear according to the FSM that both the radiator and the block should be drained), I've been interested in two things:

1. The widely varying degrees of difficulty people have in freeing up the block drain....in the experience of some it's easy, for others it's been a nightmare. I must admit, the latter cases make me a bit reluctant to do it myself.

2. The inconsistency of professional mechanics (both indies and MB techs) as to whether or not they drain the block.

So I wonder: if you walked into your and and simply said, "Replace the coolant," would they drain the block? If not, why not? Laziness? Ignorance? Don't think it matters for some reason?

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14 E250 Bluetec 4Matic "Sinclair", Palladium Silver on Black, 154k miles
06 E320 CDI "Rutherford", Black on Tan, 172k mi, Stage 1 tune, tuned TCU
91 300D "Otis", Smoke Silver, 142k mi, wastegate conversion

19 Honda CR-V EX 61k mi
Fourteen other MB's owned and sold
1961 Very Tolerant Wife

I expect a fully equipped shop has ways of flushing cooling systems we can't replicate in our driveways. This is the first I hear of using vacuum -

http://www.youtube.com/watch?v=-P98HrCl-G4

Sixto
87 300D

This guy needs to back to grammar school -

http://www.youtube.com/watch?v=VMyoyzowkJI&NR=1

Sixto
87 300D

In general I would think that on average when one of us does it to our own old MB it would be done more carefully and fully....

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1980 240d ,

chain elongation, cam marks reference:
http://www.peachparts.com/shopforum/diesel-discussion/10414-help-i-need-check-stretch.html

http://www.peachparts.com/shopforum/diesel-discussion/305365-9-degrees-chain-stretch.html

evap fin cleaning:

http://www.peachparts.com/shopforum/diesel-discussion/156207-photo-step-step-post-showing-w123-evaporator-removal-1983-240d-1982-300td.html?highlight=evaporator

A/C thread

http://www.peachparts.com/shopforum/diesel-discussion/297462-c-recommendations-mb-vehicles.html

I agree, you cannot pay ANYONE enough to do a job well today, its all about time and money. Flushing takes time along with citric acid, etc but most shops will R&R and that's it. What is distressing to me is to pay a pro good bucks and then go back in months later and discover what they have forgotten or broke -pisses me off! Do it yourself and sleep well at night -my two cents, good luck

X2

That's why were here sharing information.

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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!

To do it right, might take 4 hours @ $75/hr shop time, plus materials and overhead. Would anyone b@#ch about a $350-$400 bill to "Change coolant, flush block"? I didn't think so.....

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80 300SD (129k mi) 82 240D stick (193k mi)77 240D auto - stick to be (153k mi) 85 380SL (145k mi) 89 BMW 535i 82 Diesel Rabbit Pickup (374k mi) 91 Jetta IDI Diesel (155k mi) 81 VW Rabbit Convertible Diesel 70 Triumph Spitfire Mk III (63kmi)66 Triumph TR4a IRS (90k mi)67 Ford F-100 (??)

Sounds like it's almost guaranteed to be a unverisally-neglected procedure....virtually no one would pay several hours labor for a coolant change. Which also makes it a virtual certainty that my block drain plug has never been touched!

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14 E250 Bluetec 4Matic "Sinclair", Palladium Silver on Black, 154k miles
06 E320 CDI "Rutherford", Black on Tan, 172k mi, Stage 1 tune, tuned TCU
91 300D "Otis", Smoke Silver, 142k mi, wastegate conversion

19 Honda CR-V EX 61k mi
Fourteen other MB's owned and sold
1961 Very Tolerant Wife

Next time you pay your mechanic for something and he has the car on the lift, get him to break loose the plug ( but not drain) on the block. Then take it home and DIY and take your sweet time about it.

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80 300SD (129k mi) 82 240D stick (193k mi)77 240D auto - stick to be (153k mi) 85 380SL (145k mi) 89 BMW 535i 82 Diesel Rabbit Pickup (374k mi) 91 Jetta IDI Diesel (155k mi) 81 VW Rabbit Convertible Diesel 70 Triumph Spitfire Mk III (63kmi)66 Triumph TR4a IRS (90k mi)67 Ford F-100 (??)

Just because a business has a shingle hanging out that says "Mercedes Repair" doesn`t always means they know every little detail of every model. many shops are "All European Repair". meaning they are generalists.

Even going to the dealer doesn`t mean you are going to get the quality of service you would expect. these old MB`s we all own are far older than the majority of the mechanics working there.
I was 33 when the first 77 W123 was sold, and now 67. so the majority of the experienced are retired.
you may find some younger mechanics that have a passion for these old diesels, but they are probly far and few between.

I would bet the block drain plug would not be removed. shops are looking for the fastest way to get a car in and out and get to the next project. It is all about time and money. their time, and your money.

Most people wile rise to the level of their incompetance.



I removed the plug on my old engine in the 85 about 4 years ago, and as I remember, it came out w/o too much trouble.
I would say, "Just do it"

Charlie

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there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works

If the issue is fluid renewal/purity, that can be easily achieved by multiple drains of the radiator. For most of us, that's easier (albeit slightly more expensive) than draining the block. So, realistically, what's the practical disadvantage of never draining the block? What degree of crud/sediement are we talking about here? What is it that eventually fails or is damaged if the block is never drained?

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14 E250 Bluetec 4Matic "Sinclair", Palladium Silver on Black, 154k miles
06 E320 CDI "Rutherford", Black on Tan, 172k mi, Stage 1 tune, tuned TCU
91 300D "Otis", Smoke Silver, 142k mi, wastegate conversion

19 Honda CR-V EX 61k mi
Fourteen other MB's owned and sold
1961 Very Tolerant Wife

I don't have info for a MB but I see labor for a Chevy at 0.6hr to drain and fill and 1.5hr to replace thermostats, inspect system and flush.

It concerns me that the terms 'drain and fill' and 'flush' are used interchangeably in the service industry as in the videos linked above.

Sixto
87 300D