Hi everyone!

I am new to this forum but not forums in general. Personally I do not own the MB rather it is my parents car that I would like to become more knowledgeable about and work on.

The car is a 1991 MB E300 3.0 with ~170K. The outside and inside of the car are a 10/10 but there seems to be a problem with it starting, the RPM no longer working and transmission.

problem a) Transmission

This is probably the most serious of all the problem. The problem is that the tranny shifts very hard and aggressively through gears 1-3...it does seem to get a little bit better once the car warms up but overall a very bad shifting tranny indeed.

What could be the problem?

I suspect that the tranny is low in fluid...or the Flex Disk is rotten....or a bad tranny?


problem b) The RPM tach

basically the RPM no longer works on the dash. The car is not affected in any means but it does bother me that it does not work.

how can I fix it?


problem c) Hard starts

This is basically a long crank time and finally when it does start it has a sloppy start for the first 3-5 seconds and then smooths out. It is a problem b/c sometimes my mom cranks it too long because she gets frustrated with it.

I was going to run some injector cleaner as to eliminate that possibility. What could be the problem? is it a spark plug issue?


Overall the car runs a straight line and it is like riding on cloud 9 on the freeway. The steering is smooth and everything else seems to be perfect...


Thank you for all the help ladies and gents...


p.s. I did a search but my questions were not answered for my particular car

 

Welcome!

a) When was the last time the fluid + filter was changed?

b) You will need to pull the cluster out and replace that "part". I guess you could fix it yourself if you are handy, but I have never done it. You cannot buy that section separately so maybe find someone who is selling a whole cluster for cheap or go to a local junkyard and pull one. Easy swap.

c) Check spark plug condition and go from there. Last known tuneup?

 

a) If I am not mistaken it was around 20K - 30K ago when both the tranny and engine were pulled so that the leaks can be fixed

I have a feeling they might have poured the old fluid back in...so I may just change it again just to be sure...

i) what type of fluid do I need?
ii) What brand?
iii) how many quarts of fluid?
iv) I have done it on BMW but never on a Merc...is it similar? I have the bently book but is there a write up of pdf one for the merc?

b) dang I didn't know the whole thing had to be changed...hmmm I will look on eBay and check out some junk yards

c) I think the last tune up was performed around 120K or so but I think when I get some time on my hands I will change out all the filters again (fuel, air) , spark plugs, and run an injector cleaner...

I forgot to ask..is it normal for these engines to burn oil? I have changed from Dino to 10-40W high Mileage Mobile 1 hopping to get better results...

 

It is common, but normal no. Your valve stem seals are probably rock solid and will need to be replaced. Just be aware the longer you leave it the more plugged your cats / o2 sensor will become. Some people will say the 103 burns regardless, but if the valve guides + seals are good, you should see zero loss (my wagon has lost none since I rebuilt the head).

If you are in doubt of the fluid replace it. Any dex III will work. I like either Redline Synthetic (since yours was fixed for leaks) or Valvoline Maxlife Dex III

Do a complete tune up -- Spark plugs/Ignition wires/rotor/cap/fuel filter/air filter and go from there. Shouldn't cost you much.

 

Hmmm that does not sound good...as far as the oil burning goes...I will leave that till last....no point to go for the big problem if the tranny is junk

I have extra DEX III from my BMW tranny oil change so I will most likely stick with that...is there a write up on the procedure on the site? I have read some things about having to tilt something with a 27mm socket to get the excess oil???? what is that? where is it?

as far as the tune up parts go...I did a rough shop around online and it seems to be about $100 bucks...not bad...

 

Seems like a logical choice. I doubt there is any issues. Shifting hard is a good sign that can be softened via bowden cable or vac modulator as I said earlier. Delays or slipping is bad.

It will be more along the lines of $300. Stick with Bosch.

The 27mm socket refers to turning the crankshaft so you can gain access to the drain plug on the torque converter. ~3quarts in the pan, ~3quarts in the torque convertor. You must drain both or it is pointless

I have a short DIY on my sticky for tranny fluid IIRC.

 

Needs a major tuneup like everyone says, MB says every 30k you do plugs (bosh non resistor COPPER CORE), rotor, filters (trans/oil/fuel) grease a bunch of stuff like the linkages. Wires are usually ok, that car has a fuel distrib. and they are notorious for getting gunk in them and causing problems so try the fuel cleaner with some highway miles see if you can clean it out. Also order some new fuses, the old type are lead and get corrosion creating a bad connection, bad connection could be the problem with the tach too. Push on the cluster hard and see if the tach starts working again, maybe it was pulled once and just not reseated properly.

-Mike

 

The following is what I have decided I need...let me know if I either missed something...picked the wrong thing...or need something

thanks
0030945404


Mann (OES)
Air Filter
Q1030002


Mercedes (OE)
Antifreeze/Coolant; Antifreeze; 1 Gallon SUPERBLUE


ATE
Brake Fluid; Super Blue Racing Brake Fluid; 1 Liter
7978


Bosch
Spark Plug; SuperPlus Heavy-Duty; Yttrium Electrode
1262770295


Mann (OES)
Transmission Filter 007603-010100


Fischer & Plath
Transmission Gasket/Bushing/O-Ring; Aluminum Seal Ring at A/T Converter Drain Plug;; 10mm Aluminum Seal Washer; 10x14x1mm
007603-010112


Fischer & Plath
Transmission Gasket/Bushing/O-Ring; Drain Plug Seal; 10mm Copper Seal Washer; 10x15x1mm
1262711180


Woco
Transmission Pan Gasket
000000-000648


Mercedes (OE)
Transmission Pan Gasket; Transmission Pan/Torque Converter Drain Plug;; 10mm Drain Plug; 10x1x8mm

 

Non-Resistor spark plugs, those are resistor. The ignition wires have resistance built into them so you will be doubling up which is not good for your spark.

Go with Bosch H9DC (NOT HR9DC) or equivalent.

I bet that ATE brake fluid is expensive. Get some nice DOT3/4 at a local walmart for cheap. It will work. Coolant though -- stick with MB or Zerex G05 (same product).

 

I searched google but did not find anyone who sells H9DC so I went to the Bosch site and they recommended the H9DC0...same thing?

http://www.boschautoparts.com/Vehicl...CAT=SparkPlugs

as far as the ATE brake fluid goes...it is only 15 bucks but makes a world of difference...I first used it on my race bike and was blown away by the performance then put it in the bimmer and loved it so I have a feeling it should be worth a try in the merc

http://www.autohausaz.com/search/pro...@Brake%20Fluid

As far as the coolant goes I think I might just go with the Z-05 being that I have 2 gallons sitting in the garage!


When I went to look for the fuel filter I noticed that there were in-tank and out-tank ones...do you which one I would need?

http://www.autohausaz.com/search/pro...@Fuel%20Filter

 

H9DC0, yep same thing.

Zerex G05, not Z if that was not a typo...

Fuel filter is external. It sits next to the fuel pump near the back under a plastic cover.