Newbie needs advice - 88 420SEL 174K
 

New to the board and MB's.

Replaced tie rods, center link, idler arm bushings and front brakes.

On the schedule: lower ball joints, upper arms,
motor mounts, timing chain, tensioner, rails, valve stem seals,

Any suggestions that would fall under "while I'm at it" ?
Bushings? Which?

Thanks in advance,

Please !!
 

Can no one offer any wisdom?

Thanks,
Mike

Well you've covered what I'd probably tell you to do (which is basically the timing chain,etc) with the 126...if you have the paperwork with the car, check to see if the PO already had it replaced since this should be done about every 100k miles. If its been done, you can either do it now anyway, or you'll have a little while to get to it later. I was also gonna tell you about watching the levels with your hydraulic system (my 560 having this system) but I see you have a 126 without this system.

Other than that, your baby's pretty much bulletproof although I personally have been replacing relays,etc within my engine compartment just for the heck of it because they'll eventually go since the car is 15+ years old (I keep the old parts if they're still in what I think is in pretty good shape and just put them in the new parts box and "file" them on my MB shelf-just in case). Another thing with the 126 would be the infamous radiator neck being pretty delicate and subject to breaking (you may want to pull your upper hose and check it). This is another thing I replaced as a preventive maint. issue that will help prevent you from having to spend a mint replacing your engine because the radiator blows a hose at the most unopportune time.

Are there any issues that you "see" or "hear" that concern you with the car at all?

I have the same car as you (84K), purchased last summer. I have done most of the things you list but also had to have the transmission rebuilt. I lost reverse. I've read that the B2 piston in the transmission is subject to failure and should be replaced, however, when my transmission was rebuilt the mechanic said the B2 did not have to be replaced. You might asks. Apparently, it's now a big deal. When I had the the timing chain replaced I asked that the rails also be replaced but the mechanic said they didn't neew replacing. He did replace the chain tensioner. Still, I worry about the rails.

I forgot to mention that you might want to have the wheel bearings repacked. And, one of the annual service items is to replace the brake fluid (which I have yet to do).

Yeah, as far as regular maintenance, everything that is required for you to do is done on miles, and the items are clearly listed in your maintenance book, except two (2) items, which are done on time. They are brake fluid replacement (every two (2) years), and coolant replacement (every three (3) years).

I know a lot of people probably don't do this because it isn't in the maintenance manual, but I'd also flush and refill my power steering fluid along with a new filter (better than having to replace or rebuild a pump).;)

Think about Caliper renovation kits - seals can go and pistons stick.

I have seen the damage an overheated 420 engine can cause. While you are at it - check the viscous fan, water pump, pressure cap and change the thermostat - flush and refill with MB antifreeze.

I bought an '88 420SEL, which was a grandparents' car with 75,000 miles and totally refurbished it; see:

http://www.peachparts.com/shopforum/mercedes-benz-cars-sale/28337-low-mileage-refurbished-88-420sel.html

This (along with the other suggestions above) is just about everything one would need to do -- the frontend investment gives a solid road car that should, with continued regular service, provide dependable service for some time -- and they're not nuilding them like battleships anymore!

Thanks
 

Thanks for all the shared wisdom.
Only "repair records" I have is the maintenance book from the
original PO (ending at 95k). It seems the second PO used indy
shops and kept no records (yikes).
That is why I'm opting to do as much PM as makes economical
sense. I have added a A/T fluid & filter change, and rear rotors/pads to the list.
There seems to be several areas of oil/fluid leaks including the A/T and PS pump that will need to be addressed.

DJNEWK2, what symptoms should I look for on the rad neck?
LAKELOVER, I have repacked the wheel bearings, they look shot.
Added them to the to-do list. Bought Speedbleeders & will do
the brake fluid this weekend.
MOEDIP, I will certainly give the cooling sys some atten. What
is the "viscous fan"? Why MB antifreeze?

Thanks again,

Caliper Rebuild?
 

MNORTON,

How difficult is a caliper rebuild? Is this a DIY project?

Thanks,

Viscous fan - the cooling fan behind the rad - not the electrical aux fans. The viscous fan changes speed with temperature - spinning slowly when not required and speeding up as heat requires it to. If bad will not speed up all thew way causing higher engine temps.
Mercedes Antifreeze is designed not to attack plastic or hoses - read article from MBUSA - NA antifreeze deteriorates plastic (hence rad neck breaks)Using MB antifreeze - according to the article allows hoses to last up to 15 -20 years. Some disagree with this - some agree - you can draw your own conclusions - I am switching to MB antifreeze on my 560sel when it comes out of winter storage.

calipers
 

Actually, all I meant was to remove the pistons from the calipers and replace all the seals and dust seals with a caliper repair kit; as the calipers get older, sometimes bits of rust can work thru seals and get into the bore, causing seized pistons - it's an easy job, just the same as on any car you'll find, but you have to get the pistons out by pumping them out with pedal, unless anyone else knows a different way.

bribenz - on my 560sel viscous fan was semi -freewheeling when engine was cold - not pumping much air - fan speed increased slightly as you revved engine but was still not locked up. When engine was hot - same thing and engine temp climbed to over 105C. I put a new fan viscous unit in. Now when engine is hot - the fan locks up and pulls maximum air. I don't know for sure - but I believe the air temp the fan pulls through the fan produces the lock up. From what I have read - the viscous fan was used as means to increase gas mileage with less torque required from the pulley when the fan is not needed. If my understanding is wrong - can someone please explain why the viscous fan is used instead of a solid mount fan that is locked at all times?