Back to Mercedes, 1991 300 SE, 27,500 Mi - PeachParts Mercedes-Benz Forum

Steve Gutman · #1 09-10-2013, 08:10 PM

Hello All,
I have been mostly absent for a few years on this forum but I did it again. The last Mercedes was a 1985 500 SL AMG. Had it 13 years and sold it at 145,000 miles. Loved that car. Performed tons of service to it.

I recently bought a 1991 300 SE with 27,500 miles. It's not perfect but very good. It had a frozen caliper from deferred maintenance (metal to metal) so I replaced the calipers, rotors, pads, hoses and hardware. Everything but the wheel bearings. I forgot how difficult the old ones are to service properly. Had to repack and set wheel bearing clearance. I flushed the brakes with 800 cc per caliper and ready to run. I have to replace the original tires and all the rest of the fluids. I want to keep it as a Sunday driver. It's never seen snow and I hope to keep it that way. I hope to contribute here and will be asking questions for sure.
Steve

PARSHOOT1 · #2 09-10-2013, 10:13 PM

Tell us where you found your low mileage ride?

Steve Gutman · #3 09-11-2013, 12:58 PM

Between 2002 and 2008 I was looking for a 300 SE in the late 126 chassis for easier service and fewer (problematic) options, to use up as a daily driver. I tried to buy a few but there was something amiss with each deal. I gave up and bought a BMW.

A few years ago, a customer told me he owned this car and I told him how much I wanted one. He did not want to sell it and had it stored in a (his) house that his daughter is using. She started driving the car and he decided to sell it so it didn't get messed up. She drove the bad brakes metal to metal until the caliper froze. He called me on the phone and I just had to buy it. The Benz's were off my radar and I didn't want another car but I just had to buy it, after looking for years. Lucky that my wife said okay!

Steve

Gilly · #4 09-11-2013, 01:08 PM

At that age you might want to consider just doing the valve stem seals now. Also maybe the lip seal.
Great cars, this is the kind to find, the last year or so of production.

Steve Gutman · #5 09-11-2013, 04:50 PM

Hello Gilly,

Thanks for the advice. I think I will drive it for a summer or two if I see no symptoms. First thing is to change the rest of the fluids. I hope to keep it in excellent condition.

Steve

S-Class Guru · #6 09-12-2013, 07:12 PM

Wow! I've owned a '91 300Se for 22 years now; probably seen it all in that time - and forgotten most of it! She's now an official member of the family.
My only real complaint with the car is the transmission gearing - it takes off in 2nd and can't get out of its own way, and it screams at 3500 RPM when doing 70 on the highway. Just the wrong engine/tranny/differential in an otherwise great old car. But she's OK for around town.
Yeah, do all the fluids. Drain the torque converter along with the pan and filter. Change the power steering filter and fuel filter. Check all the rubber in the suspension and driveline; particularly the grease boots on the tie rods and ball joints and rear axles. If the valve seals are bad (and they are if they have not been changed) you will know it pretty soon; it'll use a quart of oil in 300 miles on the highway.
If you want info on just about anything regarding this car, just search on my posts; every conceivable issue is probably discussed.

Welcome!!

DG

Steve Gutman · #7 09-13-2013, 04:00 PM

Hello DG
I will be searching your posts for sure. Even with the low miles I expect to be making up for deferred maintenance. Do the rocker arms come off to change the valve seals? How tough is that job? New valve cover gasket necessary as well?
I had a R107 and have done the trans fluid. The drain on the torque converter is great. I have done P/S fluid and filter too. I will change every fluid. Need one tie rod end and tires as they are original and one has a bubble on the sidewall.
I have never lived with the car so the trans gearing you mention may not make me happy but I now drive a BMW 520i Euro car with a 5-speed stick. It runs at 3000 rpm at 62 mph. I already suffer that problem so it may not bug me too much. I sometimes hit 4000 rpm on the way to work.
Steve

lorainfurniture · #8 09-13-2013, 04:39 PM

Is it kind of weird that it went through brakes i only 28k miles? I always assumed brakes where a 50-60k replacement interval.

S-Class Guru · #9 09-13-2013, 04:41 PM

Hey Steve. Yeah, the rocker arm pedestals will need to come off to get to the valve springs. Really easy though, just 4 bolts holding each of the six pedestals down. Here are a few pointers.
- remove the oil spray bar on top of the rockers (3 little screws - Loctite them back in).
-Loosen each pedestal's 4 bolts in sequence about 1/2 turn at a time, to relieve the spring pressure evenly (or turn the motor over by hand to get both cam lobes off the high point). Retorque value is 21Nm. no Loctite.
- Leave at least one pedestal attached to hold the cam in place.
- Put the pedestals back in the same location, they are slightly different.
- Watch out for the little spacers/ball sockets between the rocker arm tip and the valve stem - they will fall off and find a bad place to land. Use a magnet to grab them, and stuff a piece of rag or something in the big oil return holes in the top of the head just to be safe (these holes eat valve spring keepers also).
- The intake and exhaust valve seals are different - should be marked on the package - the exhaust ate 9mm, the intake 8mm.

Yes, get a new valve cover gasket - really cheap, and they get pretty brittle.

Seems the MB and the Bimmer are geared virtually the same - 3K at 62 MPH.
So, may not bug you. Actually, you can't even hear the engine on the highway, just annoys me to see the tach doing that much for hours at a time - increases wear on the accessories also. I bet that mushy take-off in 2nd will get to you though!
but, 22 years later you couldn't pry her away from me, so must not be too bad.

Cheers,
DG

Steve Gutman · #10 09-13-2013, 05:29 PM

Thanks DG,

I'll order the parts and look for a free afternoon. Do you recall if the engine turns clockwise facing it form the front? I heard BMWs can snap the (hollow) camshaft if you don't.

The trans works the same as the 500 SL I had. If you put it in gear 3, not D, it starts in first. You do have to put it into D to get 4th. There are a couple guys who can modify a circuit board and give you a first gear start, but I never bothered.

More later,
Steve