I just bought a nice 92 400E but know nothing about the "bad habits" of this new V8. I know the 103 and 104 engine like the back of my hand but have ventured down a new road. Any advice about what to look out for like wiring harness/head gaskets/ oil leaks etc. would be a huge help and save alot of time on the learning curve. I noticed a significant oil leak on the front of the engine...is this a known problem? Thanks folks.

 

Congrats! Pics?

 

First off, Congratulations! It's a truly great car.

1. The wiring harness! Replace it immediately, if it hasn't already been done. When it goes, it goes quick... You might want to replace the vacuum lines in the engine bay at the same time. Tons of small problems will either disappear, or never be seen in the first place. The V8 engine bay runs hotter than the sixes, so the insulation deteriorates faster, and in more places.

2. I'm sure I don't have to tell you that oil leaks are always a problem, for a lot of reasons. The magnitude of the repair depends on the location, of course. But the leak may be (or also be) from one of the lines going to/from the transmission oil cooler. I had a small leak there when I bought my car, replaced a fitting & tightened all visible clamps, & haven't dripped a drop of oil since. Leaking oil is /not/ inevitable with these engines -- and I have the garage floor to prove it. Also absent are the head gasket problems common to the sixes.

3. The wiring harness!

4. This is an odd one. The car is very much less 'impressive' in a lot of ways than you'd think. Bear with me here. A lot of folks are used to econo-boxes (& a lot of not-so-economical boxes) that howl, shake and shudder, making a BFD, at anything over 75mph -- or when stopping from that speed. But press on the right-hand pedal & the car Just Goes. Press on the left one, and it Just Stops. No squealing, screeching or fireworks. It takes some getting used to.

First day I had my 400E I'm driving down a deserted stretch of freeway late at night, about 12:30am, & just digging it, you know? Playing with the CD, finding my radio stations, fiddling with the heater, etc. Cruising along, I glanced at the speedo -- and I'm doing 110mph. Uphill. Didn't have a clue.

OTOH, it's way fun to blow off Vettes, Porsches, BMW's, & even other Benzes, who don't even see you, because the only outward difference between your eight bad boys & a diesel is the trunk badge.

5. Did I mention the wiring harness? The OVP relay is often mentioned on these forums, but I haven't had any problems with mine (so far).

6. The interior wood trim is Burl Walnut, not Zebrino. Burl is used only on the V8's (400E & 500E) which was cool then, but because only a very few were made, makes finding replacement trim pieces a pain. Virtually every other non-engine[*] part, though, is identical with the 300's -- which means there are bunches of bits & pieces around, both OEM, aftermarket, and junkyard.

7. It's a great car. Strong as an anvil, and more than fast enough to get you into a Whole Lot Of Trouble in a big hurry -- but with the handling & brakes to get you right back out, and so smooth & quiet doing so folks might not even notice.

Again, congratulations. You're gonna' love it.

[*] edit: & non-brake

 

Congrats on the car! I love my E420 ! Great car couple minor probs but no big deal. Just a tip . If you don't know how old your dist cap and rotors are I would spring for a new set. They were the cause of most of my problems. But runs sweet now!


Smokie

 

Yes, front covers leak...as a few other areas. If it doesn't drip on the floor or smoke or use fluids up then let it weep I say.

Have the chain tensioner checked....no real need to do a timing chain unless it is noisy and close to 200K miles. Change the radiator if it runs real hot; they get clogged up and don't work so well after many years.

And put some stiffer shocks on it...like Konis. Good choice , btw, you'll have many years of happy motoring if you take care of it. Places like this helps alot.

 

hello

congrats!

a great car, but can be a money pit.

when you go for sevice remember your lawyer's, gun's and money!

give us the stats on your car, color,miles,options,wheels, etc.

do you have any previous maint records?

i've had to do a bunch of s-hit on mine, evaporator, power steering pump, wiring harness, major tune up, rotors and pads, fluid changes,etc.
i've dropped over $5000 in the last 2 months.

wiring harness WILL NEED changed.

i have a brand new extra one, if interested.

peter

 

I'll keep the harness in mind. PM with a price.
I just replaced both motor mounts ( they were totally shot).
I do have a terrible oil leak on the left bank, front. Seems to be just in above the power steering pump below the cam advance setup. I replace both valve cover gaskets and the cam / distributor cover on the left plus the distributor drive seal. This cover sure looked like it was the culprit. Re-sealed it but there is STILL a leak. Not as bad...but it's still there. Is it possible the headgasket is leaking out the front? No oil in the coolant though... or visa versa.
Very weird...I'm beginning to think that cover may have a crack in it.
I'll keep you posted.

 

Yes, great car, if things have been taken care of

I bought my car with a stack of receipts totalling thousands, which include changing light bulbs, detailing the interior, injector cleaners, etc.

When I purchased it, the selling dealer did the following:

All 4 shocks/struts, 4 new brake rotors/pads, new belts, resealed the p/s pump, some new temperature sensors, resprayed the pitted front bumper.

Then the following were done: (out of my pocket)

A complete 90k service ($$$$) - a pair of distributor rotors/caps, various filters, etc.

Engine Mounts (They were actually ok at 86k mi.)

Crankshaft Position Sensor

Wiring Harness and A/C Evaporator (total cost > a used older Ford Explorer)

A set of wheels and tires

.... expensive car to run but it sure is still very pretty to look at and runs like new. The engine is still very smooth, pulls great, sounds amazing.

Needless to say, I am trying to make my money's worth by keeping the car...

Next to do:
Rebush the front suspension

 

Yikes...out of your pocket. I do most all the repairs myself...always have which is why I like the MB. On this car motore mounts, gaskets etc....but I still got this darn leak. It is right around the PS pump but I don't hink it is that. Oh well, I'll keep look'n.....my next car will be a 500E...just about bought one on eBay last week but didn't hear good thing about the seller....hard to buy online.

 

the power steering pump leaks on these cars.

actually i think it's one of the hoses that really leaks.

just had my pump replaced, damn expensive.
if you do the DIY thing you can re-seal it.

also vacuum lines to or from transmission leak.

how long did the valve cover gaskets take?

did i miss it or have you not yet told us car color, miles, etc?

tell us about the car

 

Thanks for that..I'll look at the lines on the PS pump. The valve cover gasket took a couple of hours. No big deal...only one bolt on each side a pain...it is at the back on the bottom and very close to the heat sheild and almost impossible to get a wrench on. Be sure to use a torgue wrench when re-installing. Over torgue can cause leaks.
The car is Diamond Black (199M) on Black with 225K kilometers...in Canada...and no rust on the body. Nice car. I have a 97 E320 that is full of rust....just a mess. Awful car. That's one of the reasons I went back to the W124 body. The W210 is a nice look'n vehicle but beauty is only skin deep.

 

Well, I think I got them all...oil leaks I mean! The left front of this engine was saturated. I removed and resealed the upper timing chain cover with Locktite 5900. This is the same stuff MB recommends for the lip seal on the M103 engine...and it works!!. Plus I put a new cam seal on the distributor. This reduced the volumne, but the leak was still there. Then I removed the power steering pump ( what a job...don't believe Mitchell's, they lie!!...). It, the pump, had a couple or small issues like the bottom hose clamp from the reservoir was broken and there were two "stripped" bolts in the bottom of the reservoir that I fixed with a helicoil. STILL leaked!! Took the cam advance cover off and it even looked like oil was in there ( don't know how it got there) so I sealed it too.....still leaking...although not as bad. But what the h*** could it be? ...At this point I'm beginning to think that the headgasket is gone, but the leak is too high for that! So, took the degreaser/power washer to the whole engine...it was sooooo clean when I finished...then took the car for a slow drive , came back and you won't believe it but there was oil leaking out of the lower stud, there are 2, that goes through the head to hold the timing chain guide in place. THAT was the main source of the leak. I have no idea why. It shouldn't..unless somebody messed it up trying to remove it to do a headgasket!! The oil was just flowing out..unbelievable...and I noticed that oil was pooling in there 2 days ago, but figured it was just splashing up...NOT! Anyway, the stud was tight and since it is threaded down it's middle, for removal, I made a "plug" on the lathe... screwed it in there with an "O" ring and presto....oil leaks gone. WOW...what a pain....You guys out there with leaky oil saturated engines have a look at those studs. If they look oil filled then that is your leak. Let me know and I will send you all you need for a quick fix...for a small fee

 

Well other than that ! How you like yer car??


Smokie

 

Just bought a 1993 400E 2 months ago. Fixed D/S Window, door lock and Blower/regulator.

LOVE the car, WIRING HARNESS????

To me WIRING HARNESS has always meant, "get RID"! How difficult/expensive is it to replace? We're talking about the same thing, right? ALL the wiring in the car??


Ken
Calgary, Alberta
CANADA

 

Nope just the engine harness!! Heat issues and then you get the cracking and flaking of the insulation! Then bare wires rub where they should not and you got a **** load of probs.!!


Smokie

 

i got a decent break, i think $550.00 u.s. dollars because i bought 2.

the main engine wiring harness lists for $660.00.

total for 1 installed at stealer $625.00 u.s.

my harness was toasted at 90k.

i also have just purchased the lower engine harness, about $80.00