Hello I am a new to the forums; happy to have found such a great site via search engine.
Well I guess I should start off at the beginning I had an 89 VW GTI but due to circumstances beyond my control (nightmare mechanic, vandalism and theft) I no longer have it.
As a result I am now driving a MB’79 300D and have been driving it since May of this year the car has a little over 166,000 miles on it the odometer gave out about 3 weeks ago it’s in pretty decent shape over the past few weeks I have notices that the mileage per gallon is starting to decrease just a personal thing but watch this pretty close and know the mileage to different areas and know that I should be getting better mileage so I am thinking that maybe it’s time for new fuel filters for the engine & tank as I have read that there are two filters that need to be changed, also last week I put some diesel additive in the tank thinking this might help out the knock and idle but maybe it’s just coincidence but now in order for me to shut down the engine I have to pop the hood and manually shut down the engine I think from what I have read in the forum that this is a worn out “diesel shut off valve” that needs replaced. I know that the car has some vacuum line problems as the trunk doesn’t lock and the line has a sheet metal screw in it to plug it also there is a sheet metal screw in the engine compartment in one of the vacuum lines I am just guessing this is the hose that’s for the trunk and this is why it’s sealed, also the air-conditioner which is a must have down in South Florida works but blows very slowly when on the highest setting I have found a temporary solution to this if I put the setting on defrost it blows great just hope using this setting doesn’t burn out the a/c unit? I understand this is a 23 year old car and there are certain maintenance issues that a car of this age is going to inevitably run into it also need shocks and the front seats rebuilt now here’s my question rather than putting a lot of $$$ into the ’79 300D. I have a chance to pick up an 85 300TD with 240,000 on it doesn’t need all the repairs that the ’79 does at this time not sure what I should do? One thing for sure is the ’85 300TD is much faster because of the turbo but don’t know if I might regret getting the turbo as I have been told that the if turbo fail that it’s quite expensive to have repaired one benefit of the ’79 there is almost no way that I’ll ever have to worry about getting any speeding tickets that’s for sure. Hope what I have typed makes some since to u’s out there in cyber land.
Thanks in advance for your suggestion and comments.
Andrew M.
Also know as HogLeg
New member to this site...long question???

Welcome to the site,
I don't think there is a question here.... Get the 85 TD.
The turbo is a Red Herring.... the MB turbos are very reliable and tubos got a bad rep from GAS turbos which run very hot compared to a diesel due to the difference in the exhaust gas temperature... The turbo model will likely give you better gas mileage in addition to being faster... what a deal !

I would also pick the 85 over the 79, assuming the cost difference wasn't huge. This forum has convinced me that the turbo would be a minimal amount of complexity with a significant benefit....wish I had one on my 240D. You already are experiencing the A/C complexity issue, which I am glad I don't have with my 240D.

The problem that you described about not shutting off is most likely due to your vacuum problems. It could be a bad shut off valve, but since the shutoff valve works with vacuum, vacuum leaks are always the prime suspect. I can't tell you how many posts and ebay sellers comments I have read that say the locks don't work and it also won't shutoff!!!

Good luck.

__________________
1976 240D
1987 560SL
2007 E320 Bluetec
1998 C280 (now son’s car)
1982 240D Manual - Sold

Just wanted to say thank you for the help and suggestions about the cars and the little problem that I am experiencing at the moment planning on getting the problems fixed soon.
Sorry but one more question will it damage the engine to shut it down by hand?
Andrew M.
aka HogLeg

take it from an owner of a 1985 2.2l 190D with 77 hp- GET A TURBO!! it will prevent ulcers

No, shutting off manually (other than slightly embarrassing - did it at the office for a week), is the same as mechanical shutoff. Your manual lever is located next to the vacuum operated shutoff valve because they operate the same valve closing the flow of fuel (the only way to shut off a diesel - no sparkplugs).

I don't like a relatively high milage of that turbo. By the way, I had a choice (same owner) of a 300TD and 190D (same year). TD was actually slower. But, after reading this site, it maight have been some maintenance issue.

__________________
1985 190D 2.2l Sold-to Brother-in-law
1996 Mustang 3.8l -"thinks it's a sports car"
1988 Grand Wagoneer - Sold (good home)
1995 Grand Cherokee Ltd -"What was I thinking??!!"

HogLeg:

I like that name.....

I would suggest that you check all the vacuum line connections -- the lines are hard plastic and the connectors are rubber -- all surely dead by now. Replace them all. This should cure a number of ills.

The best tool for checking vac systems is a MitiVac hand pump, available at all decent auto parts stores for about $30. Worth every penny, too. Using the hand pump, you can check vac systems easily, and find leaks.

The reason you don't get air moving with the AC is that you have no vac to the climate control, and the servos don't work (rf they are busted and you therefore have no vac -- this is why you need the hand pump!).

To get you started -- the shutoff switch (behind the ignition switch) is supplied vac from a brown plastic line in the engine compartment. The line to the shutoff is brown with a blue stripe. Pump that line and see if the lever moves down. If so, you have a vac supply problem, not a shutoff problem. If the shutoff won't hold vac, replace it, easy to do.

The locks operate off vac supplied via a yellow line, tees to a tank under the left front fender. Line goes to a switch on the drivers door, from there to the other doors, trunk, and fuel filler door -- yellow with red strip locks, yellow with green unlocks. The T for the reservior is under the carpet, drivers side, in the wire tray, pull carpet and tray cover.

Any servo bad will prevent the locks from working -- you have to pull the door panel to get to them. They aren't too expensive, and easy to replace. Test with Mitivac, bad ones won't hold vac.

The climate control vac supply is the green line -- attach Mitivac and see if the climate control works properly. There is also a reservior in this system, takes a while to pump down. If you can't get a vac on the system, you have a leak and will have to run it down. If you do get a vac and it works, you have a supply problem.

The tranny system has white lines, go to a valve on the valve cover -- should have high vac at closed throttle, drops to zero wide open on the line to the modulator (auto tranny).

Check the connections at the main vac line for all the accessory vac systems. There is usually a restrictor there (white or yellow plastic "butt connector" ) -- if it is plugged, no vac! They get dirty with time.

Also, you can use the MitiVac to check the idle vac in the main line -- if you don't have good vac there, you probably have a bad vac pump, need to fix before the brakes get too hard.

You will appreciate the turbo -- and a new cartridge (wheels and bearings, casing just bolts on) is usually only $300-400.

Peter

__________________
1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!

If you have a manual transmision, you could just stall it in high gear. It won't hurt anything.

P E H