1985 300TD-T With Pictures - PeachParts Mercedes-Benz Forum

Adriel · #1 02-04-2015, 05:20 PM

Starting a thread on the 1985 300TD-T, as feel then I can be more disciplined as folks are watching. Plus, there will be fun and pictures!

Have my doubts it will work, but hey, never know unless we try!

Let us start with this last weekend. As we recall, rained Thursday evening all the way though early Saturday morning, then off and on though Saturday night.

I left Saturday morning and went with the A.I.A.S. to Arcosanti. Due to the rain, the dirt road was more a mud trough. Lot of fun sliding, bumping over the rough surface, and slinging mud. However, the once rain cleaned Mercedes was coved from the ground up, front to back, in mud.

Because of all the stress, turmoil, and life changes, stayed the night to recenter and think. I hiked the local butte, including sitting on a rock with the sun on my back, thinking for a very long time.

After I stayed the night, had to drive on the even more soaked road. Thankfully I had thought of parking the back wheels in the grass, so in the morning I was able to get out. The road going up the hill from the guest house is windy and steep, with one very large puddle. I couldn't help myself: I drove rally style plowing through the mud at high speed and semi sliding though the corners, all the while trying not to slide off into the river below. Man what a rush and a thrill! Once I got to the parking lot and onto the main road, was too strait, hard, and rutted to have so much fun, but I did slide around the one corner and splash through a puddle. There is so much mud all over, except the tailgate. As you can see, even splashed all over the engine bay!

So much there are large droppings of mud that dripped off during the night!

I do notice there is an advantage of having a mud covered auto: folks give you distance, especially in the rear!

Hated at first getting muddy, but has grown on me.

Today I changed my plans, as on the way home saw the idle in neutral was way too high. Normally don't put into neutral once really warmed up, but had traffic on local roads and helped not have to put so much pressure on my knee.

Saw it as her begging for attention, and one thing led to another. Idle is now about 750-800, where it sounded the best (hard using the tachometer, but first time and much better than fiddling and guessing).

Next was the fuel filter. Yes, should have been done a while ago, but I really used to dislike doing it due to fuel spillage. I came up with a way that worked much better. Noticed the short hose was loose, so might have contributed to the fuel leak, though no tracks in the fresh mud; never thought a muddy engine bay be a good thing!

Do see a lot of algae despite treatment. Does it take several treatments to cure? How about fuel filter change interval?

As you may recall, the vent line is not fully venting. I see three lines; which is the one that vents the tank? I blew into one and causing bubbles in the tank and light headedness... I only have so much air strength! l.o.l.

Plan is to pore a light tank cleaner down it and hopefully start dissolving. I rigged a couple lines onto the current rubber hose to allow fitment of a funnel.

Oh, and one line is missing the clamp and by the smell and slight wetness, been "leaking". Could explain our fuel smell.

Thank y'all for reading and the help!

Quahog · #2 02-04-2015, 06:54 PM

good looking wagon there, and the best year too

Adriel · #3 02-04-2015, 08:47 PM

Quote:

Originally Posted by Quahog

good looking wagon there, and the best year too

Thank you!

Just now realize this after two years?

Should see her when all washed and waxed! There is parking lot rash, but the paint still shines!

I do also like the '85, but some of the extra emission stuff is annoying.

What do you like about the '85 over other years?

toomany MBZ · #4 02-04-2015, 09:12 PM

Dispensing with critters in the tank is not an exact science.

How many treatments? Depends.

Change out the filters by sight, when the primary gets dirty, change it. If you're careful, there is minimal fuel spillage.

The 85's have a different rear gear, making for better mpg. The blue flying saucer helps with transmission shifting.

Adriel · #5 02-04-2015, 09:50 PM

Quote:

Originally Posted by toomany MBZ

Dispensing with critters in the tank is not an exact science.

How many treatments? Depends.

Change out the filters by sight, when the primary gets dirty, change it. If you're careful, there is minimal fuel spillage.

The 85's have a different rear gear, making for better mpg. The blue flying saucer helps with transmission shifting.

Thank you!

Well then, I will just keep at it. Obviously one treatment doesn't do it.

I have super clear filters from non-O.E.M. I am going to try. So far the opaque plastic isn't doing it for me... Yep, finally learned how to be careful.

Yep, those are also my favorites! Plus, the California oxidizer so less particulates out the exhaust. Though does make the turbocharger have to be clocked and very expensive air filter. But only need changing every 30,000 miles, so means three years for me.

jake12tech · #6 02-04-2015, 09:51 PM

Nice wagon and good year.. I like the hubbies better than the Bundt style wheels. Much more suiting to the W123. I think I spot a puppy in the driver seat..

Adriel · #7 02-04-2015, 10:03 PM

Quote:

Originally Posted by jake12tech

Nice wagon and good year.. I like the hubbies better than the Bundt style wheels. Much more suiting to the W123. I think I spot a puppy in the driver seat..

Jake, thank you!

They have grown on me also, but the '79 I swapped because I was reducing the purchase price.

In mud, wish I had not the hubcaps as get scratched.

Now if I get the 230TE I will have yet another set.

Maxbumpo · #8 02-05-2015, 11:11 AM

Quote:

Originally Posted by Adriel

Today I changed my plans, as on the way home saw the idle in neutral was way too high. Normally don't put into neutral once really warmed up, but had traffic on local roads and helped not have to put so much pressure on my knee.

Saw it as her begging for attention, and one thing led to another. Idle is now about 750-800, where it sounded the best (hard using the tachometer, but first time and much better than fiddling and guessing).

Did the idle speed change from before your trip? Sounds like you have it properly adjusted, but I'm suspicious that the muddy drive may have thrown mud up into throttle linkage which is causing some binding.

Quote:

Originally Posted by Adriel

Next was the fuel filter. ... I came up with a way that worked much better. Noticed the short hose was loose, so might have contributed to the fuel leak,

Yes, all those connections need to be tight, using the proper fuel-type hose clamps. Diesel fuel glows under a black light, so once you think you've fixed the leaks, clean off all the areas that have fuel, then use a black light to check for leaks while the engine is running and after you have driven for a bit.

Quote:

Originally Posted by Adriel

Do see a lot of algae despite treatment. Does it take several treatments to cure? How about fuel filter change interval?

If you have some microbial growth, you need to get the proper "bug killer" to dose the fuel tank. The fungus lives in the water in the bottom of the tank, and eats the fuel. The colony can get quite large, and if too big the best course of action is to get the tank cleaned. Start simple/easy/cheap, get Biobor (or similar) from a marine goods store (West Marine is a national chain) and follow the directions to dose the tank.

The fungus will die from the Biobor and may clog your fuel filters several times as they are flushed out of the tank. You probably should carry at least two sets of filters with you (and the tools and rags to change them), and be prepared to change filters on the side of the road.

Quote:

Originally Posted by Adriel

As you may recall, the vent line is not fully venting. I see three lines; which is the one that vents the tank? I blew into one and causing bubbles in the tank and light headedness... I only have so much air strength! l.o.l.

There should be two fuel lines in the engine compartment, and they should both attach to fuel tank connections at roughly the same area. The vent line is short, only visible under the car at the fuel tank, and has a little cone shaped end. Mud-dauber wasps can build a nest inside and clog it up, or maybe driving on muddy roads???

Quote:

Originally Posted by Adriel

Plan is to pore a light tank cleaner down it and hopefully start dissolving. I rigged a couple lines onto the current rubber hose to allow fitment of a funnel.

Not sure what you've got in mind here. The biobor is added via the fuel fill opening. No need to add lines anywhere to treat the fuel tank, unless you plan to pump all the fuel out, run it through an external filter to clean as much of the dead fungus at once as you can (to prevent road-side filter changes). That would be rather a pain to set up, but possible.

Adriel · #9 02-05-2015, 12:07 PM

Thank you so very much for all the help!

Quote:

Originally Posted by Maxbumpo

Did the idle speed change from before your trip? Sounds like you have it properly adjusted, but I'm suspicious that the muddy drive may have thrown mud up into throttle linkage which is causing some binding.

Idle speed has needed to be checked since I was in Oregon and Tram added a longer fuel rod. I didn't notice as most trips engine really doesn't get good and hot; only drive five miles and 15 minutes to 20 miles and 30 minutes.

Quote:

Originally Posted by Maxbumpo

Yes, all those connections need to be tight, using the proper fuel-type hose clamps. Diesel fuel glows under a black light, so once you think you've fixed the leaks, clean off all the areas that have fuel, then use a black light to check for leaks while the engine is running and after you have driven for a bit.

That is nifty! I used to have a black light, but shouldn't be hard to find.

Quote:

Originally Posted by Maxbumpo

If you have some microbial growth, you need to get the proper "bug killer" to dose the fuel tank. The fungus lives in the water in the bottom of the tank, and eats the fuel. The colony can get quite large, and if too big the best course of action is to get the tank cleaned. Start simple/easy/cheap, get Biobor (or similar) from a marine goods store (West Marine is a national chain) and follow the directions to dose the tank.

I bought and treated the tank in summer. Then I drained the tank to check the screen as was having issues, which turned out to be the vent.

For this treatment, not only did I use the anti-algae, but fuel treatment that is to help with contamination.

Quote:

Originally Posted by Maxbumpo

The fungus will die from the Biobor and may clog your fuel filters several times as they are flushed out of the tank. You probably should carry at least two sets of filters with you (and the tools and rags to change them), and be prepared to change filters on the side of the road.

Ah, so could be done and over with. Well, I am sure since maintenance dosage is one to two ounces, wouldn't hurt to do that until the fuel is clear.

I carry spares and tools at all times. It is a practice I have done since I owned a vehicle, especially older ones. I carry in the bag one main filter and at least several pre-filters. This last trip was so fast and couldn't see how bad the filter was until holding to the light. As I said, no longer going to use these opaque filters.

Quote:

Originally Posted by Maxbumpo

There should be two fuel lines in the engine compartment, and they should both attach to fuel tank connections at roughly the same area. The vent line is short, only visible under the car at the fuel tank, and has a little cone shaped end. Mud-dauber wasps can build a nest inside and clog it up, or maybe driving on muddy roads???

I am sorry, behind the spare tire. The vent tank has three lines, with two running to the tank and now that I look in the daylight, one running to an unknown, forward part of the tank bay.

My Mercedes resides in a garage, and much doubt wasps, especially since I never seen any here. Further, this mud bathing was the first time. The vent has been a issue for at least nine months, if not over a year or more.

Quote:

Originally Posted by Maxbumpo

Not sure what you've got in mind here. The biobor is added via the fuel fill opening. No need to add lines anywhere to treat the fuel tank, unless you plan to pump all the fuel out, run it through an external filter to clean as much of the dead fungus at once as you can (to prevent road-side filter changes). That would be rather a pain to set up, but possible.

I mean to clear the metal vent lines, not the feed lines.

I add additives to the tank with a funnel.

Maxbumpo · #10 02-05-2015, 12:20 PM

Quote:

Originally Posted by Adriel

Idle speed has needed to be checked since I was in Oregon and Tram added a longer fuel rod.

OK, all the throttle linkage stuff has specific lengths (or ranges the length must fall in) in order to get full sweep of the injection pump fuel rack (i.e. get full power from the car). The idle speed is (probably??) adjusted via a set screw on the back of the injection pump. I've never worked on an '85, so hopefully someone who has can chime in here. Starting with the next generation of engines (OM60x), the idle speed was set electronically. '85 123 cars are a "cross-over" and have some newer features on the IP and some older features, so I need to defer to someone with more knowledge.

In general, if you are adjusting throttle linkage stuff in order to set the idle speed, you're probably doing it wrong. My '87 wagon throttle linkage had been really buggered up by a previous "mechanic", I ended up removing all of it, setting all the rod lengths to the factory-specified length, and then put it all back together, and the change in performance was amazing.

vstech · #11 02-05-2015, 12:37 PM

Quote:

Originally Posted by Adriel

Thank you!

Well then, I will just keep at it. Obviously one treatment doesn't do it.

I have super clear filters from non-O.E.M. I am going to try. So far the opaque plastic isn't doing it for me... Yep, finally learned how to be careful.

Yep, those are also my favorites! Plus, the California oxidizer so less particulates out the exhaust. Though does make the turbocharger have to be clocked and very expensive air filter. But only need changing every 30,000 miles, so means three years for me.

what are you treating it with?

diesel fuel is dirty. it is on the verge of breaking down just sitting in the tank. startron DIESEL tank cleaner is very good stuff. power service CLEAR diesel is good as well. best time to treat is when the tank is low, and you are filling it to the brim.
put in the treatment for a full tank, then FILL THE TANK, then go driving. the sloshing action gets all the nooks and crannies, and parking the car after to let it soak into all the places that were sloshed onto.

and yeah...
several treatments if you are plugging filters. if not, just change the filter, treat and drive.

Adriel · #12 02-05-2015, 03:08 PM

Quote:

Originally Posted by Maxbumpo

OK, all the throttle linkage stuff has specific lengths (or ranges the length must fall in) in order to get full sweep of the injection pump fuel rack (i.e. get full power from the car). The idle speed is (probably??) adjusted via a set screw on the back of the injection pump. I've never worked on an '85, so hopefully someone who has can chime in here. Starting with the next generation of engines (OM60x), the idle speed was set electronically. '85 123 cars are a "cross-over" and have some newer features on the IP and some older features, so I need to defer to someone with more knowledge.

In general, if you are adjusting throttle linkage stuff in order to set the idle speed, you're probably doing it wrong. My '87 wagon throttle linkage had been really buggered up by a previous "mechanic", I ended up removing all of it, setting all the rod lengths to the factory-specified length, and then put it all back together, and the change in performance was amazing.

Thank you so very much for the help!

I am suffering from severe gut pain and cramping, so a little distracted and hazy. So when did I say I used the linkage to adjust idle?

Let me be clear: if you adjust the linkage, must at least check idle, not just cold like I did, but good and hot. Adjusting the linkage can adjust fuel amount, which of course affects idle.

Setting idle on a '85 is the same as the others: screw with 14mm lock nut located on the side of the injection pump on the inboard side.

Tram found an issue, which significantly increased performance, to the point of hard to get used to, leading to a speeding ticket (coming down a hill plowing up for the next due to performance issues which had until I came home and left the fuel cap off.).

Adriel · #13 02-05-2015, 03:16 PM

Quote:

Originally Posted by vstech

what are you treating it with?

diesel fuel is dirty. it is on the verge of breaking down just sitting in the tank. startron DIESEL tank cleaner is very good stuff. power service CLEAR diesel is good as well. best time to treat is when the tank is low, and you are filling it to the brim.
put in the treatment for a full tank, then FILL THE TANK, then go driving. the sloshing action gets all the nooks and crannies, and parking the car after to let it soak into all the places that were sloshed onto.

and yeah...
several treatments if you are plugging filters. if not, just change the filter, treat and drive.

John, thank you so very much for the reply!

I bought what you recommended at the time. Both products are made by Power Service, Clear-Diesel and Bio Kleen (what the F.L.A.P.S. had).

Is there any reason to switch?

I don't find one just for diesels, just both.

So are you saying run the quarter tank or the sloshing done when filling up?

Fine, very good! Will keep an eye on the filter and keeps at it will keep at treating.

eatont9999 · #14 02-05-2015, 06:27 PM

Nice wagon. It could use a wash, though!

It has taken me several months of StarTron treatments to remove fungus in the tank. The whole time, I get to clean out the primary filter several times per tank fill.

Maxbumpo · #15 02-06-2015, 04:26 PM

Quote:

Originally Posted by Adriel

So when did I say I used the linkage to adjust idle?

Setting idle on a '85 is the same as the others: screw with 14mm lock nut located on the side of the injection pump on the inboard side.

Sorry for misunderstanding, I just wanted to make sure the proper procedure was used.