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  #1  
Old 09-27-2001, 07:20 PM
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Location: San Jose, CA
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Question 300td

Good afternoon everyone. First I would like introduce my baby. I just got her 2 weeks ago and recently knew about this excellent forum. She is a 1983 300TD with 275,000 miles.
Now on to the problems that I notice.
1) The rear hatch doesn't lock with the rest of the doors.
2) The previous owner said that something is blowing the fuse to the rear wiper when it is plugged in. Is there a common problem to this part. When I turn the rear wiper by hand it moves easily.
3) The rear is lower than the front and when I searched the archives here, it stated that I have a self levelling suspension. I didn't know this and didn't expect it to be expensive. I thought just to replace shocks.
4) My tach is erratic. Sometimes it goes to 6000 rpm and sometimes it just stays at 0 rpm and sometimes it goes up and down. My tach jumps when I press the horn.
5) The driver seat is lower on the left than on the right part. Is there a fix to this problem. Also the passenger side seat belt doesn't lock into the part bolted to the seat.
That is all for now, hope to hear from the great people here.
Thanks in advance for the help and info to my problems.

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96 Legacy LSi wagon
92 Mitsu Expo
95 525iT
1983 300TD clackclackclack sold
1972 Toyota Corolla wagon TE28 sold
1991 Galant VR4 pshhhhh non-op
1989 Montero RS pop's ride
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  #2  
Old 09-27-2001, 07:40 PM
engatwork's Avatar
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Location: Soperton, Ga. USA
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Ahhh - the joys of putting one back right.
1) Troubleshoot the vacuum system.
2) Check the continunity through the rear wiper electrical system. Something is shorted.
3) Self leveling suspension is not cheap. Other than this knowledge I really don't have much experience in this area.
5) The seat springs need replacing.
I would recommend that if you are handy with a wrench/tools, get the manuals and learn everything about it that you can.
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Jim
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  #3  
Old 09-27-2001, 10:31 PM
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Thanks for the help. I am looking for manuals on ebay. I am ok with wrenching. Can you give me some pointers on checking the vacuum system. Where can I get the lower part of the seats?
Thanks again. Any other suggestions from owners who have these same experiences are appreciated.
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96 Legacy LSi wagon
92 Mitsu Expo
95 525iT
1983 300TD clackclackclack sold
1972 Toyota Corolla wagon TE28 sold
1991 Galant VR4 pshhhhh non-op
1989 Montero RS pop's ride
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  #4  
Old 09-27-2001, 10:37 PM
SW SW is offline
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Location: Houston, TX. USA
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My driver's seat did the same thing when I bought my car. I took the seat out, turned it upside down and found a spring to be broken. I unbolted the seat bottom and my father took it to his work place and got the broken spring welded and bolted a small split sleeve around it. The repair is holding up well 1 year and 3 months later.
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2001 Dodge Ram 2500 Cummins Turbo Diesel - 4x4, auto, 3.54 gears, long bed
-------------------------------------
'92 300D 2.5 Turbodiesel - sold
'83 300D Turbodiesel - 4 speed manual/2.88 diff - sold
'87 300D Turbodiesel - sold
'82 300D Turbodiesel - sold
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  #5  
Old 09-27-2001, 10:56 PM
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Thanks for the tip. I'll check it out this weekend.
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96 Legacy LSi wagon
92 Mitsu Expo
95 525iT
1983 300TD clackclackclack sold
1972 Toyota Corolla wagon TE28 sold
1991 Galant VR4 pshhhhh non-op
1989 Montero RS pop's ride
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  #6  
Old 09-28-2001, 02:13 PM
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300TD, great car!

Congratulations on your new acquired 300TD.

I had a 1981 300TD which kept for 18 years. Loved every single minute I had it, although I had to regretfully sell it after my S320 came into the scene.

I sold it with 72,000 original miles on the odometer and in perfect condition (the spare tire was the original in brand new condition, never used!).

For the time frame I owned it, the self-levelling rear suspension was one of the things that gave me the most trouble. You could do a search in the replies I have posted and find more about it.

Also had problems with the vaccum system, changed the radiator and the water pump once, and had to constantly clean the injectors due to the poor quality of the diesel here.

Happy driving!

A. Rosich
S320, 1998
E320T, 1995
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  #7  
Old 09-28-2001, 02:53 PM
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Location: Eastern TN
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Erick,

Glad to see you on the forum.

3) It could be as simple as adjusting the level control valve or as expensive as needing new hydraulic parts. You'll need to follow the prescribed diagnostic steps on this one.

4) Do a search on 'cigarette butt' (don't laugh, it works) to find a common fix for a wild Diesel tach.

5) Many folks say it's easy to repair broken springs. I've never done it. Consider replacing the seat bottom. I believe the newer seat design in common between 83-85 sedans and wagons. I'm sure someone can verify. It might be possible to use a seat bottom from a coupe or from a 77-82 sedan or wagon. It's easy to take these seats apart.

Sixto
91 300SE
81 300SD ... buy me
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  #8  
Old 09-28-2001, 06:58 PM
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thanks

Thanks for the replys and tips. I'll search for those topics and hopefully fix some this weekend. Wish me luck.
__________________
96 Legacy LSi wagon
92 Mitsu Expo
95 525iT
1983 300TD clackclackclack sold
1972 Toyota Corolla wagon TE28 sold
1991 Galant VR4 pshhhhh non-op
1989 Montero RS pop's ride
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  #9  
Old 09-28-2001, 07:58 PM
someguyfromMaryland
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Welcome to the list. I have a 1980 300D and have worked on a friends 300TD so I have some experience on your car, although I will start by stating I'm no pro.

The vac system is troubleshot with a hand held vac pump. They are available for between $35 - 75, depending on how nice a pump you want. I've even seen the less expensive ones in Wal-Mart's automotive section. The good news here is that the diagnosis is very cheap, the bad news is that it might take a good while. You basically have to go through the system and test isolated sections until you find a) a leak, b) a failed vacuum motor, or c) the failed vacuum pump. The pumps are robust but occasionally do fail. Once you've found the problem, the repair should be obvious.

I'll leave electrical troubleshooting to the electrical guys on this list. I'm crude but effective on electrical theory and you're better off not hearing how I chase electrical problems.

The self levelling rear has only four major components: two shocks, two Nitrogen charged pressure spheres, pump, and a hydro-pneumatic compensator linked to the rear axle. The last piece is what gives the self-levelling to the system. As the rear is loaded, the shocks compress, lowering the chassis closer to the frame. The compensator senses this change and sends more pressure to the shocks until the body is back where it is supposed to be. I've always heard that unless the shocks are leaking, they're to be assumed good. The N2 spheres de-pressurize over time and are a common cause of the droopy butt look on these wagons. They are fairly simple to replace and are < $100 each through places like Fastlane. The compensator is also fairly robust, I'd start by looking at the N2 spheres.

For the tach, refer to my electrical guidance above.

For the seats, almost any of the 5 million 123 chassis in boneyards around the country have a seat that would fit your car. Look for a gas engined 123, like a 280E. They usually were put down earlier than the diesels and can be found with <100k miles on the clock. Seat wear is a function of butt time more than age, so a passenger seat spring will have less wear than a driver's seat and a low mileage car will have less wear than a higher mileage car. You can remove the seat covers and mix and match, as needed, to get what you need.

The passenger seat belt sounds like it needs a new buckle. I've never heard of anybody wearing one of those out, so I'd look in a boneyard for that too.

The really good news is that you have a car that can be brought back to life with a substantial savings by using "previously owned" parts. Obviously the N2 spheres, shocks, etc, need to be purchased new. Once freshened up, these cars hold up very nicely as they were all built with 300 k miles.

Enjoy!

someguyfromMaryland
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  #10  
Old 09-28-2001, 09:35 PM
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Location: Evansville, Indiana
Posts: 8,150
Wagonboy:

Sorry to be the bearer of bad news, but "dragging butt" on the self leveling usually means a bad pump or bad struts -- if the pressure spheres go the suspension is locked. You won't have any trouble figuring that out, the car bounces like mad and you cannot push the rear end down by body weight. Those are cheap, the struts aren't -- about $650 each last time I asked. No one wants to fix them so there are lots of self-leveling cars out there drooping.

You get the same effect, eventually, if the pump is bad or the fluid has leaked out, so check that, too. If you are lucky, you only need to fill the reservior and fix the leak (although if the fluid has been gone a while, the pump is also probably shot!). Get a good manual and troubleshoot it properly before you start buying parts -- they get expensive quick.

Seat springs are readily available from any part supplier who can get MB OEM parts. They are a couple hundred bucks, no more, maybe less. I'd replace the seat belt end -- it is bolted to the seat frame, I think -- get one from a junkyard, they are all the same.

TDs are great! I bought my mom an 88 TE last year for a very good price -- pressure spheres were shot, AC didn't work, etc -- got everything fixed now except the flex disk and tranny pan leak!

Peter
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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!
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  #11  
Old 09-29-2001, 03:43 PM
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Location: Plano, TX
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I'll toss in my $.02 as well. I owned an '84 300D sedan and currently have an '87 300TD wagon, so I've had all these problems, just spread across two cars...

I find all the advice given previously to be quite sound. I'll just add some elaborations and clarifications.

Does your central locking system work after the car has been parked for more than a few minutes? If so, you probably don't have a vacuum issue with the rear tailgate, but some other problem causes it not to lock/unlock. When the vacuum motors fail, they generally leak such that five minutes after the engine has been shut off, the central locking system is inoperative - the vacuum reservoir is drained. I'd disassemble the interior trim on the tailgate and look for a problem in the mechanical connection between the vacuum motor and the locking mechanism.

BTW, you get good at troubleshooting the vacuum portion of the lock system. I sold my old sedan to a friend. He brought it over for a few repairs last week, one of which was an inoperative central locking system. Took me 10 minutes to run through the system with my mity-vac and identify the problem as a failed actuator for the gas flap.

Rear suspension - you got a problem. Does the car come up to normal height when driven, but sinks back down later? The rear struts provide both the shock absorber action and the self leveling. The control valve admits additional oil - under high pressure - to the accumulators as the rear suspension is loaded down. The additional oil increases the pressure in the rear strut/accumulator system, causing the struts to raise the back of the car. There is also a minimum pressure below which the control valve will never permit the system to fall. This minimum pressure is necessary to get adequate damping out of the struts. Without it, the rear end drags, and you effectively don't have any shock absorbers.

Look under the rear of the car - way under - and you can find the control valve. It's silver, about 3" across, and has a small arm on it. The arm is attached to the rear sway bar via a linkage. (The sway bar rotates as the rear suspension is loaded and unloaded, moving the arm up and down.) Disconnect the linkage and - with the engine running - move the arm up. The rear of the car should raise. Lower the arm, and the rear comes back down. I use this trick to work under the back of my wagon - it's faster and easier than jacking it up. Of course, insure there is oil in the reservoir under the hood. BTW, the system requires a special mineral oil. It's absurdly priced at the dealer, but can be ordered for ~$10/liter.

BTW, the struts for the rear suspension are quite expensive - I've generally seen $275/each. I bought a new control valve for my 124 wagon - I bet it's exactly the same as yours - for $140. Lemme know if you need the name of the vendor. The nitrogen sphere accumulators run $80-$90 each. It's possible to get the accumulators recharged with nitrogen - this is normally what they do over in the Citroen world. Of course, you can't drive the car while they are shipped out to the Citroen specialist. If you're a real cheapskate, perhaps source a pair from a junkyard and send them out to be recharged. I think pricing is in the vicinity of $12/each for recharging. I've got a contact or two filed away if you need them.

Tailgate struts. Good pricing is about $45/each, though they are occasionally seen on Ebay for less. Just make certain you prop the hatch open so it doesn't slam shut when the first strut is removed. (No, I don't know this from experience.)

Seat springs: Just buy a new seat spring base. You can install your present upholstery on it. About 2 hours work, pretty durn easy job. To do the job correctly, you should also replace the rubberized horsehair pad. However, I cheaped out and got some upholstery foam from the local fabric store. (You'll be the only guy in there.) The spring base costs about $100 mail order. Makes a huge difference in how much you like the car.

'Nuff rambling for now.
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  #12  
Old 09-29-2001, 08:36 PM
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thanks everyone

I would like to thank everyone for giving a lot of tips in making my baby better. The rear end is not stiff, on the contrary it is soft and I can wiggle the rear end with just body weight.
So, hopefully nothing is messed up and all it will need is adjustment of the lever. Tomorow, I will hit the junkyard for the seats and the lock for the seatbelt.
Wile messing around in the engine compartment, I noticed that the hose that goes into the egr valve is disconnected and plugged with a screw. What would make the po do this. I got new vacuum hoses and plugged it back into the egr. Any info on this is appreciated.
People from CA, where can I get Mobil DElvac, also where can I get a Haynes or Chilton manual? I went to Kragen's earlier and they don't have the 123 manual.

Thanks again everyone. Btw I tried the cigarette butt on the sender and it made the tach better but when I hit some bumps it still jumps around although not as bad before.
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96 Legacy LSi wagon
92 Mitsu Expo
95 525iT
1983 300TD clackclackclack sold
1972 Toyota Corolla wagon TE28 sold
1991 Galant VR4 pshhhhh non-op
1989 Montero RS pop's ride
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  #13  
Old 09-30-2001, 11:39 AM
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Location: Evansville, Indiana
Posts: 8,150
The tach sender suffers from poor solder connections, and if they are bad enough, the cigarette butt fix won't work -- it puts pressure on the connections to hold them together.

The EGR reduces milage and power a little, and can cause horrendous smoke and drivability problems if it sticks open. I would imagine the PO disconnected it to either increase performance or "fix" a defective valve. If it works OK connected, leave it, or you will fail an emmisions test one day.....! If you get funny engine rattle and huge clouds of smoke at low speeds, it is sticking open and needs to be replace. Ditto if there are soot markd around the base of the vacuum can -- the shaft seal is shot. If you don't want to fix it, at least plug the line with something like a BB and put it back on the valve -- since you live in CA, you will get fined for having it disconnected if you get stopped for an emmissions check!

I have plated the one in the Volvo off, pending finding another one that costs less that $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!
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  #14  
Old 09-30-2001, 12:49 PM
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smoke gets in your eyes
 
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Location: Eastern TN
Posts: 20,841
I have some question about the symptoms and diagnoses.

- if the nitrogen spheres go bad, the suspension gets stiff, but there's no effect on height, right?

- if the struts go bad, the car rides low, but there's no effect on stiffness, right?

- I see wagons with the rear level and low, but always even left to right. Is it not common or possible for only one strut to fail causing listing?

And a general question:

- what is the function of the nitrogen spheres?

MB purists should skip this question:

- is it possible to retrofit old fashioned air shocks with an air compressor and adjust the ride height manually? Maybe Gabriel should reconsider their product naming strategy these days.

Thanks,
Sixto
91 300SE
81 300SD
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  #15  
Old 09-30-2001, 02:41 PM
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Since I am no tech expert, I would jump to your last question:

When the self-levelling suspension on my 300TD failed, I ask around to see if I could get away with a conversion to a regular step-up like the one the sedan uses. Well, according to every expert, it is impossible to do so. So, I'll guess it would be also impossible to switch a to an air regulated level control.

The rear geometry of the suspension from the T and sedan series is completely different (due to cargo compartment clearance). Also, almost every component is different.

A. Rosich
S320, 1998
E320T, 1995

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